AGRICULTURAL CHEMISTRY AND VEGETABLEPHYSIOLOGY.THE record for the year 1905 was concerned largely with the“search for nitrogen,” or, rather, for means by which that widelydistributed, though inert, gas could be made to lend itself to theservice of agriculture. This question remains the prominent one to-day, and elver and again hopes have been quickened by some newand startling announcement, and it would seem, indeed, that theday is not far distant when the falling-off of the supplies of nitrateof soda from South America may be contemplated with resignation,and the atmosphere, with its vast store of nitrogen, be laid undercontribution to agriculture’s needs. The work of the year 1906has brought this prospect somewhat nearer, although perhaps notvery materially so, and development has hardly taken any newform.Just as the year 1905 closed a new revelation was promised asregards the behaviour of plants in relation t o their power of utilis-ing nitrogen, but closer examination has shown the views thus putforward to be untenable.At the close of 1906, there was, simi-larly, promised a new discovery, whereby at’mospheric nitrogencould be cheaply utilised. I n each case the details were not athand a t the time of writing, and so it has not been possible t o domore than merely chronicle the event. But it is evident that deepinterest must attach to researches in this direction, both from thescientific and the practical side of agriculture. The great problemis, of course, how the nitrogen of the atmosphere can be bound upin some form in which it can be transported t o the land and theremade use of just as nitrate of soda and other nitrogenous materialsare. The ways already discovered of effecting the union ofnitrogen and oxygen, which have resulted in the productionof cyanamide on the one hand and of calcium nitrate on the other,have been further exploited with the view of removing the onegreat obstacle to the general employment of these materials-namely, their cost of production.It is in this direction that thelatest discovery is stated to tend, Meanwhile, information is beinAGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 257accumulated as t o the practical uses and comparative values ofthese materials so far as their limited supply allows.I n another direction attention is being turned to the work oforganisms in the soil, and to the conditions under which some ofthese, a t least, have the power of elaborating nitrogen into formsavailable for plant use.For the moment, the direct inoculation ofleguminous crops, to which so much attention has hitherto beengiven, seems to have been dropped, and there is little that is newto record about it. But in regard to Azotobacter and other soil-organisms, much further work has been done, and our knowledgeregarding their action is beginning to shape itself into form.Similarly, inquiry has been pursued as to whether plants do not,in some cases, take up ammonia directly.I n regard to the root action of plants, more evidence has beencollected in support of the contention that there is no externalaction of the root sap itself, but that it is the excretion of carbondioxide from the roots which assists the solvent action of the soilwater.Striking proof has been afforded of the important partwhich calcium carbonate plays in respect of plant life and cropproduction, whilst the special place which magnesia occupies hasalso been investigated.The inquiry into green-manuring has been continued, and furtherresults have been obtained which bear out the conclusion previouslycome to that green crops act very variably, and that the deductionsformed from theoretical considerations are not borne out in farmpractice.Much work has also been done with regard t o the question of“strength” in wheat and what is implied by this, but strongindications are given that the solution of the problem will notcome from the chemical but from the biological side. Differentbranches of the work of the Rothamsted Experimental Station havebeen summarised in various useful ways, among which may bementioned a survey, by N.H. J. Miller,l of the amount and com-position of the drainage water through unmanured land, as recordedat Rothamsted from 1870 until the present time.A distinguishing feature of the year has been the revival ofinterest in the sugar industry, and reference is made t o severalpapers dealing with questions affecting this industry.I n India the advance indicated in last year’s report has been verymarked indeed, a thorough scheme of agricultural investigationhaving been now set on foot.An Imperial Department ofAgriculture 2 has been formed, comprising eleven different. appoint-1 J. Agric. Sci,, March 1, 1906, 377.Annual Report sf Imp. I)ept. of Agric?dture, 1904-5, C a h t t a , 1906.trm. III. 258 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.ments, included in which are those of an inspector-general, adirector, an agricultural chemist, two botanists, an entomologist,and a bacteriologist. Provincial Departments have also beenestablished in Bengal, the Punjab, and the Central Provinces,whilst the existing Departments in Madras, Bombay, and theUnited Provinces have been strengthened. I n the Bombay andCentral Provinces there is also an agricultural chemist attachedin each case to the Department.Altogether, the staff of Government experts, which four years agonumbered six throughout India, has now been increased to twenty-five.A research institute has been opened a t Pusa, in Behar, andincludes fully-equipped laboratories for research work, an experi-mental farm, a cattle-breeding farm, and a higher agriculturalcollege.The Indian Tea Association has continued its investigations withmore assiduity than ever, and, under its able expert, Dr. H, H,Mann, has put forward some really excellent work, more especiallyon the subject of the fermentation of tea. The account of Dr.Mann’s investigations shows most clearly how well-directed sciencemay be utilised for the benefit of an industry. Under the direc-tion of the Imperial Department, scientific aid has also been givento the, unfortunately decaying, indigo industry.The obituary for the year includes the names of Prof.AlexanderMuller, of Sweden and Berlin, and of Prof. Adolph Emmerling,of Kiel. The former was the organiser of the first agrico-chemical“ Versuchs-Station ” in Stockholm, and was specially known forhis work on moor soils, on the nature of milk constituents andthe influence of foods on the composition of milk, as well as, laterin Berlin, for his researches on the utilisation of sewage and thepurification of streams. Emmerling was best known for his re-searches on the formation of albumen in plants.Among publications may be noted a new edition (8th)of “ Church’s Laboratory Guide,” which has been thoroughlyrevised and practically rewritten by Prof.Edward Kinch, of Ciren-cester, also the I‘ Microscopy of Vegetable Foods,” by A. L. Winton(Connecticut, U.S.A.), which is practically an American editionof Dr. Josef Moellsr’s well-known work, “ Mikroskopie der Nah-rungs und Genussmittel.”Nitrogert.(a) Calcium Nitrate.It is €0 the direct combination, through electrical force, of thenitrogen and oxygen of the air that attention has been mainlyturned, the process briefly described in last year’s report, anAGRICULTURAL CHEMISTRY AND VIUETABLZ PHYSIOLOGY. 259resulting in the production of calcium nitrate, being the one thatseems t o offer the greatest prospects of ultimate success. Theproduct, so far as obtainable, has been tried practically, and withsatisfactory results.The entire matter of the development of theprocess into a regular industry turns purely upon the question ofcost. Though calcium nitrate has been made, and used, it cannotyet be said t o be a regular article on the market; there is ncprice quoted for it, nor is it open to anyone to purchase a supplyof it, or to use it just as he would any other artificial fertiliser forhis soil. Even where i t has been tried experimentally, it has beenprocured with difficulty, and, up to the present, it cannot be saidthat there is more than a pure “estimate” of the cost of itsproduction. I n such circumstances the whole question of thematerial becoming a regular article of commerce, and competingsuccessfully with nitrate of soda, depends entirely on its productiona t a cost which will enable the nitrogen in it to be supplied a t alower rate than the same amount of nitrogen in the form ofnitrate of soda. Though the works of Birkeland and Eyde, a tNottoden (Norway), continue to turn out a certain quantity ofcalcium nitrate, it does not seem that the process can, as yet, beprofitably worked ; otherwise, calcium nitrate made by this processwould, by now, be a regular article on the market.Other workshave been established at Ludwigshafen, and also in Italy. At aquite recent date, however, has come the announcement of a new“discovery,” with which the names of Crookes and of 5. vonKrowalski and I. Moscicki, of Freiburg, Switzerland, are associated.The details are still wanting, but we are led to suppose that thenew method really consists in some improvement, possibly intechnique, on the Birkeland and Eyde system, whereby greaterefficiency is attained, and the calcium nitrate produced a t a lowercost than before.It has, at the same time, been stated that themethods are entirely different from those in use in Norway, thatthere is a higher percentage of “ output ’’ than by any other system,and that ‘‘ pure concentrated nitric acid ” is produced. Naturallyone must await, and with interest, the further details of thisdiscovery, but, whatever be the outcome, it would seem to be fairlyestablished that the process can only be worked a t places whereenormous water power is available, and hence there is no likelihoodof England becoming a producing country.From the few recorded experiments which have, so far, been madewith calcium nitrate, the following may be noted.J.Sebelien,’ using the basic calcium nitrate suggested by R.Messel, found the results, as between this and sodium nitrateJ. Landw., 1906, 54, 159.s 260 ANNUAL REPOItTS ON THE PROGRESS OF CHEhlISTRY.yielding the same amount of nitrogen, to be somewhat variable.Where better results were obtained with calcium nitrate this wasnot infrequently proved to be due to the lime in the calcium nitrate,for, when lime was added to sodium nitrate equally good resultswere given. On a peaty soil calcium nitrate did as well withcereals as did sodium nitrate, and this was also the case with grassland.The latter experiments were carried out in Norway. Theseresults are only what one would expect, and, as has been pointedout, there is no reason why calcium nitrate should not do as wellas sodium nitrate, whilst, where lime is deficient in a soil, it mightbe expected to be superior, because of the lime it supplies t o theland. .(b) C yanaJmide,The production of calcium cyanamide has continued, and, to judgefrom the. experiments made with it, it would seem to be moregenerally obtainable than calcium nitrate, though it, too, cannot yetbe reckoned as a staple commercial product, or to have a regularmarket price quoted for it. Experiments made with it on cropshave given variable results, some observers holding that it givesequally good results as ammonium salts, others distinctly limitingits practical application to particular kinds of soil and to particularconditions. Its use on soils containing much vegetable matter(humus) is generally agreed upon as not being attended withbenefit.F.Lohnisl states that the nitrogen of calcium cyanamide israpidly transformed into ammonia in April and May, and that itsaction on crops is very like that of ammonium salts. C. vonSeelhorst and A. Miither: in carrying out pot-culture experi-ments with it, found that on sandy loams and loams it didquite as well as ammonium sulphate, but that in sand culturesi t was injurious to vegetation. They attributed this to the presenceof some calcium carbide, and showed that if iron oxide was addedto .the sand the injurious action was prevented.H. vonFeilitzen3 came to the same conclusion as regards cereals on sandysoils and loams, but states that on peaty soils calcium cyanamidehas very little effect with oats or potatoes. J. Sebelien4 likewisefound that calcium cyanamide had little effect, or was even injurious,in the case of cereals grown on peaty soils; -and with grass land,in Norway, he obtained results inferior t o those attending theuse of sodium or calcium nitrate. A. Stutzer5 has carried out potexperiments on rye with calcium cyanamide as compared withCentr. Bnkt. Par., 1905, [ii], 15, 430.Chem. Centr., 1906, i, 584.J. Landzo., 1905, 53, 329.J. La?idto., 1906, 54, 159.ti Lnndzn. VersicclwStnt., 1906, 65, 275AGRICULTURAL CHEMISTRY AND VEGETAELE PHYSIOLOGY.261ammonium sulphate and sodium nitrate, and states that 68.4 percent. of the nitrogen was recovered in the crop with ammoniumsulphate, 65.9 per cent. with cyanamide, and 55.2 per cent. withsodium nitrate. I n the last-named case the nitrate was, however,applied in the autumn, and may thus have suffered loss by drainagein winter. Paul Wagner1 also finds that in “normal soils”cyanamide works quite well, but that on acid soils and on sandyones rich in humus and poor in lime its action is uncertain. Hefurther maintains that it can quite well be used as a top-dressing,if applied about February, to winter crops. He admits that ifapplied in warm weather there may be loss of ammonia.Lohnishas already pointed out objections to the use of cyanamide: thati t cannot be used as a top-dressing, nor be mixed withsuperphosphate, owing to the mixture getting hot; that i tdeteriorates in damp weather; and that, when applied to thesoil, ammonia is evolved, which is injurious a t first t o thegermination of the seed.E. Wein 2 says, as the result of field experiments, that cyanamideis as good as ammonium sulphate, and he finds i t t o be as effectiveas sodium nitrate on peaty soils, provided that they contain plentyof calcium carbonate. I n Japan experiments have also been triedby K. As6 3 on buckwheat, sesanzzcm, hemp, and rice, with resultsgenerally equal to those from ammonium sulphate and nitratle ofsoda, provided that the soil be not rich in humus.F.Lohnis has investigated the changes which calcium cyanamideundergoes in ordinary soils. He states that i t is decomposed bycertain bacteria, ammonia and, possibly, nitrates being formed.Among the bacteria capable of producing the decomposition areBacterium 1Circhiw-i and B. Zipsiense. Pure cultures of each ofthese, however, do not severally act as effectively as do mixedcultures of the two. The decomposition does not take place inboggy soils, either because the bacteria may not be there, orbecause the cyanamide is converted by the organic acids presentinto compounds that are hurtful to vegetation. The decompositionis not facilitated either by the free admission or the exclusion ofair, so that stirring the soils has no effect in hastening the change.From these various experiments it may be regarded as fairlyestablished that under favourable conditions and with suitable soils(such, mainly, as are not rich in humus or deficient in lime) calciumcyanamide is practically nearly as good, nitrogen for nitrogen, asDeutsche Landw.Presse, Aug. 18, 1906.Chein. Cmt?-., 1906, ii, 1454.BzdI. COIL Agr. T6ky6, 1906, 7, 47.Bied. Cextr., 1906, 35, 375262 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.ammonium sulphate or soldium nitrate; but that it is non-effectivei n the case of peaty soils or those with little lime in them; also thatit does not lend itself to ready use as a top-dressing, for storage, orfor mixing with other materials. To come back to the mainquestion, that of cost, it is clear that the extended use of cyanamidemust depend on whether the nitrogen in it can be supplied ata less cost than the same amount of nitrogen in the form ofsodium nitrate or ammonium sulphate; and on this point thereis, as yet, no definit'e information. It may be added that theinformation as to the cost of producing calcium nitrate is evenless certain.It is also well t o point out that, with few exceptions,the experiments so far recorded with cyanamide have been potexperiments, and, however useful these may be as an indication,they need the confirmation of field experiments before they willcommand the attention of the practical agriculturist.Suggestions have been made as t o combining cyanamide withother materials.Thus, F. T. Shutt and A. W. CharIton1 haveformed calcium cyanamidocarbonate by passing carbon dioxide gasthrough a solution of calcium cyanamide. This pro,duct, if kept lowin amount, will not injure the germination of seeds, but if thequantity be increased above 5 milligrams per 100 grams of soil,germination is affected, and with increasing quantities is quitedestroyed. Nitrification in t h e soil is also decreased, showing thatthe nitrifying organisms in it are affected. Suggestions have alsobeen made to add t o the calcium carbide, before heating, one ormore fluorides of an alkali or alkaline earth.2 By this means, i tis said, calcium cyanamide is obtained a t a lower temperature.(c) Leguminous Nodwles.It has been mentioned that work in the direction of the inocula-tion of leguminous crops with the corresponding nodules has been,for the time, nearly put aside.The experiments instituted in GreatBritain by the Board of Agriculture in 1905, and which were carriedon in 1905, both with tnhe German (Hiltner) preparation and theAmerican (Moore), were the reverse of encouraging, and in thefew cases in which these experiments were carried on for a secondyear (1906) with a cereal crop following the leguminous onesnothing of much note has been obtained. From the Continentand America one hears also of but little more done in this direction,and, a t all events, the day has not come yet when the farmer willbuy packets of '' inoculating material " for his bean, clover, andother leguminous crops.At the Woburn Experimental Farm theTrans. Boy. Soc. Canada, 1905, [ii], 11, (3), 73.0. F. Carlson, Stockholm, Eug. Pat. 15,445, July 7, 1906AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 263experiments were continued in 1906, a wheat crop being takenafter the leguminous ones. The only further point brought out wasthat, whether sterilised soil, poor soil, or rich soil was used, thewheat crop. was in each instance decidedly poorer after tares takenpreviously than after peas or beans.H. Flamand 1 has investigated, by water-culture experiments,the influence of different salts on the process of symbiosis, asmeasured by nodule development. Peas, beans, and tares were thecrops tried, and the plants were inoculated from appropriateno,dules. Potassium nitrate (1 : 10,000) altogether preventednodule formation, but sodium nitrate only did this when thequantity was increased to 1 : 2000.Potassium phosphate wasbeneficial to nodule formation in the cases of peas and tares,potassium chloride aed potassium sulphate being less so, althoughfor beans potassium sulphate was best. Calcium and magnesiumsalts generally were beneficial to peas and beans, but only calciumsulphate for tares. It'must be said, however, that there is a gooddeal that seems contradictory in these experiments, and doubt mustbe cast upon the variable results obtained with plants so very muchalike as peas and beans.(d) Direct Utilisation of Nitrogeit b y Plants.As briefly announced in last year's report, a revolution in ourideas as to the capability of plants generally to take up nitrogenfrom the air was promised by the statement of T.Jamieson, ofAberdeeq2 to the effect -that he had discovered that not onlyleguminous plants, but cereals, grasses, &c., had the power, exercisedthrough certain structures on their leaves and leaf-stalks, of takingin directly the nitrogen of the atmosphere. Jamieson rejectedthe nitrogen theory of Lawes and Gilbert, and the " nodule " theoryof Hellriegel, and maintained that because he found on plantsin their early stages certain organs the cells of which containedalbuminous matter, the nit'rogen of this was derived direct from theair, without, any process of symbiosis. Naturally such a view wasstoutly assailed by vegetable physiologists and agricultural chemists.Its untenability was shown by Bayley Balfour, of Edinburgh, whopointed out that the above afforded no proof whatever of fixationof nitrogen, and that on this theory it might as well be assumedthat every living cell of a plant, including those of the root,possessed this same property; the presence of albuminous matter init cell was no evidence of direct assimilation of nitrogen fromBied.Centr., 1905, 34, '738.3 Ayric26lt~~1 nl Research Association, Aberdeen, Report for 1905264 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.outside. Agricultural chemists also pointed out that the theorycould not be accepted unless direct experimental and quantitativeproof were afforded of the plant being placed in an atmospherecontaining a known amount of nitrogen and of its removing fromthis a quantitative amount of nitrogen.Accordingly, we have to goback upon our former ideas, and the problem of nitrogen supplystill remains with us.(e) Nitrogen Assimilation b y Soil Bncteriu.To this subject, and more especially t o the work of the organismAzotobacter ch~oococcum, much attention has been given.R. Thiele,l while allowing that dzotobncter can fix nitrogen,expresses doubt as t o whether this is an inherent property, andwhether it may not frequently, even in normal circumstances,be lost. He has worked out the conditions of temperature mostfavourable for fixation t o proceed, and points out that fixation isless according as the most favourable temperature is onlyoccasionally attained.J.Stoklasa 2 finds that Azotobacter chroococcum possesses morepower than any other species f o r fixing atmospheric nitrogen. Bothdextrose and mannitol will serve well as culture media. The formeris the better, but the addition of a little calcium carbonate isnecessary with it. Stoklasa has estimated quantitatively theamount of carbon dioxide evolved during the assimilation process ;on an average 1 gram of Azotobacter dry substance will evolve 1-27grams of carbon dioxide in 24 hours. Under similar conditionsB. R a r t l e b i will evolve 0.6 gram, and Clostridium gelatinosum0.48 gram, so that Azotobacter is much the most active. Whendextrose is used as the culture medium, lactic, acetic, and formicacids are the decomposition products, together with carbon dioxideand hydrogen.Stoklasa considers the assimilation process to berelated to the respiratory process. He differs from Beyerinck's viewthat Radiob acter has an appreciable power of assimilatingatmospheric nitrogen, but considers it a denitrating organism ; amixed culture of Azotobacter and Radiobacter has less power ofassimilating nitrogen than a pure culture of Azotobacter, andRadiobacter will reduce the greater part of the nitricacid t o free nitrogen, whilst a certain proportion is fixedin the form of orgmic bodies, chiefly nucleo-proteins. S. F.Ashby3 has also worked on the assimilation of free nitrogen byA zotobacter chroococcum. I n making cultures of soil organisms,Landw.Tersuchs-Stat., 1905, 63, 161.Zeit. angew. Chem.,+1906, 19, 803.J. Agric. Sci. ,; 2, 'Jan. 1907, '"35AGRICULTUBBL CHEMI8TK.Y AND VEGE'l'ABLE PHYSlOLOGY. 265using mannite as a medium, he found that the greater theaeration was (namely, when less mannite was used) the greater wasthe amount of nitrogen fixed per gram of mannite oxidised.Further, when Azotobacter was present the average yield of nitrogenwas doubled. Still, fixation took place, although low in amount,even when Azotobacter was absent. The average fixation was 6.95milligrams of nitrogen for 1 gram of mannite when Azotobacterwas present., and 3.22 milligrams when it was absent. Aerationand the presence of a base would appear to give favourable condi-tions to fixation.Ashby compared the influence of magnesiumcarbonate and calcium carbonate as bases in relation to fixation.He found that magnesium carbonate delayed development a t first,but that ultimately the yield of nitrogen was larger than withcalcium carbonate. By taking soil a t different depths Ashby showedthat Azotobacter was present in greatest abundance in the soilnear the surface. H e noticed, too, that the organism would standdrying up quite well, and would produce abundant growth iffresh culture solution were poured over the mass. Hence it isclear that the organism can be carried about as dustby wind. B. Reirizel attributes the importance of a l p infixing nitrogen in soils t o their supplying nitrogen-fixingorganisms, and chiefly A zofobacter, together with carbonaceousfood.It is not the case, as has been stated, that all that algz dois t o prevent loss of ammonia in the soil.E. Haselhoff and G. Bredemann 3 ascertained that anaerobicnitrogen-assimilating bacteria (Clostridia) are abundantly present insoils and in the leaves of forest trees; the amount of assimilationis about equal t o that of Clostridium Ynsteurianum, namely, 2.74milligrams per gram of dextrose or mannite.Nitrification.S. F. Ashby3 has studied the question as t o whether anythingwill replace carbonate of lime as a base for nitrification. Kaolinand modelling clay were tried, but neither was found effective;ferric hydroxide, however, will act, but is inferior to calciumcarbonate. Ashby comes to the conclusion that a neutralammonium salt is not directly nitrifiable, but that the functionof a base is to form ammonium carbonate, which is nitrifiable.Of bases, the reaction with magnesium carbonate is greater thanwith calcium carbonate.This latter observation is confirmed byCentr. Bakt. Par., 1906, 16, [ii], 640.Landw. Jahrb., 1906, 35, 381.3 J. Agric. Sci., 2, Jan. 1907, 52266 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.S. Machida,l who found nitrification t o be favoured by magnesiumcarbonate more than by calcium carbonate.A. Miintz and E. Lain62 carried out experiments with theobject of producing nitrates in large quantity. Animal charcoalwas found t o be an excellent medium for nitrifying organisms, andwith a solution of 0.75 per cent.of ammonium sulphate tensquare decimetres produced 8.1 grams of sodium nitrate perday. If stronger solutions were used, nitrification was less active.They also tried experiments with soil to which 0.2 per cen';. ofammonium sulphate was added, and i t produced nitrates a t therate of 350 grams per cubic metre per day, which, takan t o asoil depth of half a metre, was equivalent to 1,750 kilos of sodiumnitrate per hectare. The same authors, in another communication,3show that humus, in whatever amount, is not prejudicial tonitrification, but indeed is rather favourable to it. It is not,however, necessary, as nitrification can be obtained in soils poorin organic matter. Humus seems to aid the multiplication ofnitrifying organisms, and, as a rule, a soil contains more activeorganisms and is more prone to enter into nitrification accordingas it contains more humus.Different soils showed very differenteffects as regards nitrification, and rich soils nitrified much morequickly bhan sandy or clay soils. With the same amount ofammonium sulphate a rich soil, with 17.6 per cent. of carbon, nitri-fied, at bhe end of seven days, 0.209 grams of nitrogen per kilogramas against 0.02 gram with a soil containing only 1.5 per cent. ofcarbon. Peat was found to be the best medium for nitrifyingorganisms, and by passing a 0.75 per cent. solution of ammoniumsulphate over a peat bed charged with nitrifying organisms nitrateswere formed a t a rate much in excess of anything previouslyobtained.The process of nitrification with regard to the purification ofsewage has been studied by Harriette Chick.4 The investigationswere made during the filtration of sewage.The evidence goes t oshow that nitrification takes place in two stages, and is due to theaction of two classes of organisms, the first producing nitrites andthe second converting these into nitrates. The organisms wouldseem to be the same as those which produce nitrification in the caseof soils. It may be considered strange that organisms which areso influenced by the presence of organic matter should be able tocarry on their activity; but it is pointed out that they maybe in a measure protected by other organisms with which they areThe most suitable temperature is 300.1 Bull.Imp. Centr. Ayric. Exp. Xln. Japan,.1905, 1, 1.4 Proc. Roy. h'oc,, 1906, 77, B, 241.Cornpt. rend., 1905, 141, 861. IM., 1906, 142, 430, 1239AGRICULTURAL CHEMlSTRY AKD VEGETABLE PHYSIOLOGY. 267in symbiosis, or that, while the organic matter collects mainly a tthe surface of the filter, the nitrifying organisms multiply rapidlyin the lower part of the iilter, where the organic matter is lessin amount. It has also been shown by others that if nitrifyingorganisms exist in sufficient quantity, they are able to withstandthe influence of organic matter that might otherwise destroy them.Whether the two stages of nitrification go on together o r at separateintervals depends on the condition of the sewage, whether veryammoniacal or not. If strongly ammoniacal the change intonitrates may be delayed until more of the ammonia has beenconverted into nitrites.There would appear t o be no evidencewhatever as t o the retention of free and active ammonia in cokefilters without nitrification, but that nitrification takes place rapidly.The opinion is expressed that continuous filtration is a better systemthan that of contact beds, aeration being more complete in theformer, diffusion more efficient, the distribution of the differentstages of purification better, and the facilities for cleaning greater.J. E. Purvis and C. J. Coleman1 have studied the influence ofthe saline constituents of sea water on the decomposition of sewage.They used not only sea water itself, but solutions containing thevarious salts separately, and mixed in 'the proportions in whichthey occur in sea water.The general conclusion was that bothsodium chloride and sea water hindered very greatly the productionof nitrates. Instead of the decomposition of the sewage intocarbon dioxide, water, and nitrates taking place, highly complexnitrogenous compounds seemed to remain in solution, and oxidationto proceed very slowly. The authors draw the practical conclusionthat it is a mistake to run sewage straight into the sea withoutpreviously treating it by some filtration or bacterial process.E. J. Russell and Norman Smith2 examined the question asto how far purely physical and chemical processes which take placein the soil may contribute to the formation of nitrites and nitrates,independently of the action of bacterial processes.The first pointto meet was the contention of Schijnbein that ammonium nitritewas formed during the distillation of water in air or during itsrapid evaporation. The authors repeated the experiments, andcritically discuss the work of Schonbein and his successors, andthey find no evidence whatever of the production of nitrites duringthe evaporation of water from the soil under any of the variedconditions which obtain in it. Further, they find no evidence ofthe capability of the soil to effect the combination of nitrogen andoxygen. Oxidation of free nitrogen may, they think, possibly takeJ. Xniiit. Inst., 1906, 27, 8, 433. ' J. Agric. Sci, 1. March 1906, 444268 BNNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.place by induced oxidation processes, but the evidence accumulatedwould lead to the conclusion that this is at best an unimportantsource of the production of nitrates under natural conditions.The development and distribution of nitrates in field soils hasbeen observed by F.H. King, J. A. Jeffrey, and A. R. Whitson.'I n the surface soil, to a depth of 1 foot, nitrates increased fromApril t o June, and then there was a decrease, due prnbably to rapidgrowth or heavy rains. Nitrates were much less abundant in thesecond foot of soil than in the first, and in a dry season there wasa tendency for nitrates t o accumulate near the surface. Furtherdeterminations made between November and April showed thatthere were no niore nitrates in the soil after the winter frosts thanbefore these set in.D e n i t r if; cu t ion.R.Hornberger,2 by exposing leaves of oak, beech, &c., for a,year to air and rain, found that in the majority of cases therewas a greater loss of nitrogen than gain of it.The influence of carbohydrates and organic acids on the deni-trification process has been investigated by J. Stoklasa and E.Vitek.3 The micro-organisms studied were grown in a solutioncontaining sodium nitrate, potassium, calcium and other salts,along with the particular carbohydrate or organic acid. Clos-t ridium gelatinosum produced, in the case of dextrose, ammoniamost freely. BacilZus suhtilis gave ammonia best when lzvulose orgalactose was the carbohydrate. Bacterium Hartlehi in arabinosesolutions formed much organic nitrogen, and arabinose generallyproved a better medium than xylose.Organic acids, again, wereexcellent media for the decomposition of nitrates t o elementarynitrogen, and for the formation of organic nitrogen com-pounds. Further investigation as t o the stages in whichthe action proceeded showed that the denitrification processtook place in two steps, the first being the reductionof nitrate to nitrite by means of the hydrogen formed alongwith carbon dioxide by the decomposition of the carbohydrateor organic acid through the enzyme of the micro-organisms. Fromthis it is argued that the carbohydrates in a soil are more likelyto serve for the purpose of converting nitric acid into ammoniathan as nutrients for denitrification bacteria.J.Stoklasa, J. Jelinek, and A. Ernest 4 further show, fromexperiments with sugar-beet soils, that the organic matter in the soilAgr. Exper. Stat. Univ. FViscoitsiiL, 20t7~ Animal Rcpoyt, 339.Bied. Centr., 1905, 34, 726.Y=Zeit.rZuckerind. B o h , 1906, 31, 67. Ibid., 30, 283AGRICULTURBL CHEMISTRY AND VEQEI'ABLE PHYSIOLOGY. 269is not a suitable source of carbon for denitrifying organisms, andthat nitrates are not, to any material extent, reduced ta nitrogen.When soils are well cultivated, and hence well aerated, loss ofnitrogen will not occur, though nitrates may be reduced to nitrites.Decomposition of hTitrogenous Matter in Sod.F. Lohnisl found that Bacillus mycoides and Bacterium vulgarerespectively converted within three weeks 39 and 28 per cent.ofthe total nitrogen of bone-meal into ammonia; George 8. Fraps,ssimilarly, found the organisms producing ammonia from nitrogenousfertilisers to be most active during the first week; after the thirdweek their influence decreased and nitrification was more marked.ATitrogen iiz. Rain.J. W. Leather has determined the amount of nitrogen presentas ammonia and nitrates in a year's rainfall a t Dehra Dun andCawnpore (India). He obtains the following figures for a completeyear : -iVitrogen.Parts per millioii. Pounds per acre.Rainfall, As As nitrateinches. ammonia. and nitrite. ammonia. and nitrite. Total.Dehra Dun 86.48 0'104 0.070 2.037 1 -368 3'405Cawnpore . 49'36 0'221 0.068 2-482 0.768 3.2507These figures do not differ widely from those found at,Rotliamsted, where the total nitrogen is 3.840 lb.per acre, madeup of 2.712 lb. as ammonia and 1.128 lb. as nitrates and nitrites,so that no countenance is given to a general belief that the Indianrainfall is richer in nitrogen than that of England. At DehraDun, however, where thunderstorms are more frequent; than a tCawnpore, it is noticeable that there is considerably more nitrogenpresent as nitrates. At Cawiipore the dew was also collected andanalysed, but difficulties connected with the collection are great.The results, so far as obtainable, show a total of only 0.111 lb.of nitrogen per acre during the year, this being equally dividedbetween that existing as ammonia and that as nitrates.The totaldew was 0.170 inch, and therefore, as a supply of combinednitrogen, cannot be considered of importance.H. Ingle4 has done the same in regard to the rainfall collectedCeritr. Baht. Pa?.., 1905, [ii], 15, 430.J. Amer. Chem. AOC., 1906, 28, 213.Imp. Bept. Agric. Annz6al Report, 1904-5 (Calcutta, 1906), 56, .I T ~ m s v a a l Agric. J., 1905, 4, 104270 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.a t Pretoria (South Africa.) The rainfall of 24-31 inches per annumsupplies 7.670 lb. of total nitrogen per acre, 6.587 of which occuras ammonia and 1.083 as nitrates. The total nitrogen, it will benoted, is about double that of Rothamsted, and the proportionpresent as ammonia relatively higher.N. H. J. Miller 1 in statingthe results of the Rothamsted rainfallin regard t o nitrogen and chlorine contained, gives a summary ofresults from 30 different places in tropical and non-tropicalcountries, and points out that great differences in climate do notcoincide with material differences in the amounts of nitrogenbrought down by the rain, but that, whilst in non-tropical countriesmost of the nitrogen is present as ammonia, in tropical countriesthe proportion of nitric nitrogen is relatively higher.The subject of rainfall in connexion with drainage throughuncropped land has led E.J. Russell2 to examine more closely theRothamsted results obtained respectively with the 20 inch, 40 inchand 60 inch drain gauges there. He observes that the relationbetween the evaporation from the three gauges is not constant;a t first evaporation from the 20 in.gauge is lowest, then it increases,exceeds that of the 40 in. gauge, and, after twenty years, that of the60 in. gauge as well. He attributes the variations to a “secularchange” in the drain gauges, and suggests that this is due to adecrease in t,he amount of organic matter in the soil of the gauges,and to the action of rain in washing out the finest particles, thisresulting in an increased evaporation of water.Green-Manuring.Allied t o the “ nitrogen question ” is that of the supply, throughgreen-cropping, of nitrogen to soils. The experiments on thissubject, recorded for 1903 and 1904 in last year’s report, havebeen continued a t theWoburn Experimental Farm? and the resultsfor the wheat crop of 1906 succeeding green-manuring in 1905, arenow available. Once more it appears that, contrary to theory,the ploughing-in of a non-leguminous crop (mustard) has givena better return in a subsequent corn crop than has that of aleguminous crop (tares).The green crops were cut and weighedpreviously t o being turned in, the tares giving 7 tons 2 cwt. greenproduce per acre, containing 1-05 per cent. of nitrogen, and themustard 5 tons 10 cwt. per acre, with 0.46 per cent. only of nitro-gen, the organic matter being nearly alike in amount in the two.When, however, the subsequent wheat crop came to be weighed,the results were :J. Agrie. Sci., 1, Mar. 1906, 377. Ibid., 2, Jan. 1907, 29.J. Roy. Agric.Soc., 1906, 67, 299AGRICULTURAL CHEMISTRY' AND VEGETABLE PHYSIOLOGY. 2'9 1Produce of wheat per acre, 1906.Corn. Straw.Bushels. Cwt. qr. lb.After tares ploughed in ......... .. 24'5 17 1 24After mustard ploughed in ... . . . . . , 37 '6 28 0 15Thus the leguminous crop (tares) has once again failed t o producethe larger crop which one would expect t o accrue from the largersupply of nitrogen.Humus.c- A \S. Suzukil has observed the conditions under which humusformation goes on in soils. Dry powdered oak leaves were moistenedand mixed with some humous soil; magnesium carbonate, calciumcarbonate, potassium phosphate, and other substances were thenseverally added in different flasks, and their action studied whilehumification of the leaves proceeded.The author found thathumification proceeded parallel with the Eormation of carbondioxide ; that magnesium carbonate promoted the development, andthat calcium carbonate retarded it, whilst potassium phosphate hada favourable effect.A. D. Hall, N. 13. J. Miller, and N. Marmu2 have devised animprovement in the estimation of carbon in soils and similarsubstances. Recognising that the chromic acid method of Wolffgives too low results owing t o incompleteness of oxidation, they haveproposed t o add a short tube containing red-hot copper oxide t ocomplete the combustion. They find that by this means they canconvert all the carbon into carbon dioxide, and the results agreeclosely with those of combustion in oxygen. The convenience ofthe method is that,, by adopting Brown and Escombe's modifica-tion? they can first determine the carbon dioxide present as car-bonate in a soil, and then, by attaching the copper oxide tube,they can, on the same sample and in the same apparatus, estimatethe organic carbon.Lime and Magnesia in Soils.Continued interest has been shown in the important part playedby lime in soils, and also in the significance of magnesia, and itsrelation to the lime present.The Woburn Field Experiments4afford the most striking example of the absolute need of lime ina soil, more especially under the influence of the continuousapplication of ammonium salts, these latter bringing about, inBull. Coll. Agric. Tdkyd, 1906, 7, 95.Trans., 1906, 89, 595.Phil.Trcms., 1900, 193 3, 289.J. Boy. Apic. Xoc., 1906, 67, 284, 285272 SKNUAL REPORTS ON THE PROGRESS OF CHEMISTRk'.absence of lime, an acid condition of soil and absolute sterility;fertility, however, is restored by the use of lime. This restorationwas effected by applying 2 tons per acre of lime (1897). Laterexperiments have been directed t o seeing whether smaller quanti-ties would suffice, and in 1905 lime was applied in smaller quan-tities (5 cwt., 10 cwt., and 1 ton per acre respectively) to landpreviously incapable (through the continued use of ammoniumsalts) of bearing a crop. Among the striking results may bementioned the following : -Manures per acre.Ammonium salts, without lime .................................9 , ,, with 5 cwt.lime (1905) .....................? ,, with 2 tons lime (1897) .....................Mineral manures and ammonium salts, without lime ......>, 9 , 9 , ,, with 1 ton lime3 ) >, ,, ,, with 2 tons lime(1905) ...(1897) ...Wheat,1906.BushelsCorn.3.419'226'1---Bar 1 e y ,1906.BushelsCorn.no crop11'625'41-733.944'3Incidentally these results also show that the influence of an appli-cation of two tons of lime to the acre will last for quite nine years,the dressings put on in 1897 still showing their effects. F.Wohltmann, H. Fischer, and P. Schneiderf state that manuringwith lime increases the power of decomposing nitrogenous substancesin soils, and that both nitrification and denitrification are assistedby it.M. Hoffmann2 instances experiments extending over fiveyears, and showing the general benefit of lime, even leguminousplants (lupins) profiting by it. R. Ulbricht? however, finds thatwith lupins, vetches, and serradella the application of lime producesa slightly diminished assimilation of nitrogen and phosphoric acid,the magnesia in the plants being a t the same time considerablyincreased.Investigators in Japan have continued their inquiries intothe relations of h i e to magnesia in soils as affecting theyield of crops. Thus, G. Daikuhara4 showed that the yield ofbarley in a soil having the ratio CaO : &!go : : 0.34 : 1 was doubledwhen, by the addition of calcium carbonate, the ratio was made1 : 1. The same author, experimenting with tobacco, found thatif the ratio of CaO t o MgO, in a soil of 1 : 1, was increased byliming to 2 : 1 or even 4 : 1, benefit was obtained.The latterproportion corresponds to the ratio of these constituents in theashes of tobacco. With flax and spinach S. Namikawa5 obtainedBied. Centr., 1905, 34, 805.Landto. verstbchs-slat., 1906, 63, 321.Bull. Imp. Ceittr. Agr. Exp. Stat. Japan, 1905, 1, 13,Birll. Coll. Agr. Tciky6, 1906, 7, 57.2.16id., 1906, 35, 12AGRICULTURAL CIIEMISTRP AND VEGETABLE PHYSIOLOGY. 273the best results by making the ratio of CaO to MgO 1 : 1. On theother hand, S. Maki and S. Tanakal showed that if land be over-limed, it may be benefited by adding magnesium sulphate to it.Manuring with magnesium sulphate has been tried in severalinstances (magnesium carbonate being difficult to obtain in Japan),and it is found that it has about seven times the efficacy ofmagnesite, so that when magnesium sulphate is used the ratio ofCaO to MgO should be 7 : 1, whereas with magnesite i t shouldbe 1 : 1.Interesting as these results in regard to lime and magnesia are,it has to be remembered that the experiments have been with pot-culture only, and they need the confirmation of field work. Itwould be very desirable to gather experience from field soilscontaining lime and magnesia in different relative proportions, andto ascertain if the general results obtained in pot experiments holdgood in actual practice.Phosphates.D. N.Prianischnikoff 2 has experimented on the relative value ofdifferent phosphates, I n sand culture the effect of bone meal wasabout 50 to 60 per cent.of that of soluble,phosphates, and when acrude phosphate, like phosphorite or apatite, was used, althoughgramineous crops improved very little, lupins did so considerably.I n sand cultures ammonia salts had the power of rendering evenvery sparingly soluble phosphates available for the use of plants.The same author,3 working with aluminium phosphate and ironphosphate, found that millet, vetches, and mustard, grown in sand,would assimilate the phosphoric acid from aluminium phosphate,either when merely dried or when ignited, as also from iron phos-phate if merely dried, but not if ignited. Rye and wheat, how-ever, could not utilise the phosphoric acid of crude phosphates,although lupins did as well with crude phosphate as with bonephosphate.Different processes have been suggested for rendering rawphosphates available for use.One of these is that of the WoltersPhosphat. Gesell~chaft,~ in which raw phosphates are melted in aSiemens’ furnace with alkali silicates and lime, the product beingthen led into cold water, when nearly all the phosphoric acid isfound to be soluble in citrate solution. The materials suggestedfor use are:-Tricalcium phosphate 40 per cent., silica 30 percent., lime 14 per cent., soda 16 per cent.Bull. Coll. Agr. Tiiky6, 1906, 7, 61.Landw. Versuchs-Stat., 1906, 65, 23.Bied. Centr., 1905, 34, 741.Eng. Pat. 9183, April 18, 1906274 ANNUAL REPORTS ON THE PROGRESS 0%' CHEMISTRY.The influence of phosphoric acid on straw has been observed byD.Lienau and A. Stutzer,' who conclude that it promotes thethickening of the cell wall. This effect is, however, greatlydiminished if much potassium, calcium, or nitrogen is present. Thesmaller the amount of total ash and of potassium in the straw,the greater will be the thickening of the cell walls; the appli-cation of phosphates has the effect of reducing these quantities,whilst the amount of phosphoric acid in the straw is found notto be itself dependent on the quantity supplied as manure.G. Andre2 determined a t various stages the phosphoric acidand nitrogen in the sap of certain quickly-growing annuals (Papauerand Pyrethrum), with the result that the nitrogen in the sap wasshown in general to diminish as the phosphoric acid increased.Healso found that in annuals a portion of the phosphoric acidmigrated, as soluble mineral phosphate, from the leaf to theovule, while another portion is removed in combination withnitrogenous organic substances.W. Windisch and W. Vogelsang 3 have investigated the natureof the phosphoric acid that occurs in barley grain. I n making acold-water infusion of barley they found that this containedphosphoric acid of which a considerable portion was in theinorganic state. But when the infusion was made in such a wayas t o exclude the action of enzymes, the whole of the phosphoricacid was found to be in the organic state, and they conclude thatraw barley contains no inorganic phosphates, but that these areonly produced when the organic compounds are, as in the steepingand malting processes, subjected t o the hydrolytic action of theenzymes.W. Zaleski? from eaperiments with seedlings of Lupinusangustifolius, has come t o the same conclusion regarding the actionof enzymes on proteins containing phosphorus, and shows thatinorganic phosphates are in this way produced.A. D.Emmett and H. S. Grindley5 have similarly examined thephosphorus-containing substances in flesh, and find that in beef 75per centl. of the total phosphorus is soluble in cold water, andthat one-fourth of this consists of organic compounds.This change goes on better in the dark.Landw. Yer~uchS.-Xtat., 1906, 65, 253.Conipt. yetad., 1906, 142, 106, 249.a Woch.Brau., 1906, 23, 516.Chem. Centr., 1906, ii, 893.J. Amer. Chem Soc., 1906, 28, 25AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 275Auailabaity of Phosphoric Acid in Soils.A. D. Hall and A. Amos1 have further investigated the meansof determining the amount of plant food-especially phosphoricacid-which may be reckoned as being immediately " available " forplant food. They criticise B. Dyer's citric acid method, and pointout that, although very useful, it must be regarded as purelyempirical, inasmuch as it is based on the now generally abandonedtheory of the excretion by roots of acids other than carbon dioxide.The American method of using a X j 2 0 0 solution of hydrochloricacid is similarly criticised.Both leave out of account the nature ofwhat is left in the soil, and presume that this will not in turn become'' available " until the soil has undergone a further weatheringprocess. Many circumstances, such as cultivation, the supply ofwater, the nature of the crop grown, &c., will cause variations inthe amdunts of the constituents assimilated by the crop. This hasled Whitney t o regard the soil water as the important matter ofconsideration, and as possessing a constant composition for all soils,being always in equilibrium. Hall and Amos accordingly adoptedthe plan of attacking the soil continuously with the solvent, removingthe first portion of the solution after equilibrium had been attained.The remainder of the soil was then attacked with a fresh portionof the solvent, and so on.A t first the solvent employed was carbondioxide and water, but, because of the difficulty of filtration, andthat some of the soil got into the extract, this was given up infavour of a 1 per cent. solution of citric acid. A period of twentyhours, with constant agitation, was found to suffice for the firstseparation, and to remove as much phosphoric acid as was extractedwhen the process was continued for five days. The solution wasremoved, the soil washed free of acid, and then again agitated witha further quantity of solvent. The calcium carbonate originallypresent was practically all removed in the first extraction, and nosteps were taken to restore it. I n the second extraction less thanhalf the amount of phosphoric acid was removed, in the third aboutone-half that obtained in the second, and, finally, by the time ofthe sixth extraction the quantity removed by each successivetreatment became constant.Experiments were then made on the soil to which dicalciumphosphate was added, and it was ascertained that some of thephosphoric acid soluble in the citric acid was retained in the solidstate by the soil.After a fourth and fifth extraction a point wasreached where the compound remaining in the soil was uniform.Z'mns., 1906, 89, 205.1' 276 ANNUAL REPORI'S ON THE PROGRESS OF CHEMISTRY.But this poiut of equilibrium varied in different soils, indicatingdifferences in the nature of the phosphoric acid compounds in soil.Whitney's theory of the formation in soils of solutions ofapproximately constant composition, and independently of thefertilisers used, is thus not supported, and it would appear thatthe soil water is of varying concentration in different soils.Theavailable phosphoric acid is shown by the sum of the phosphoricacid removed in the first four or five extractions; but as this hasB constant ratio to the amount dissolved in the first extraction oftwenty hours, for all practical purposes a single extraction gives asgood a result as repeated ones.G. S. Frapsl states that aluminium, iron, and calcium phosphates(as in phosphorite, vivianite, apatite, kc.), dissolve completelyin iV/5 hydrochloric and nitric acids under soil conditions.Conducting pot experiments with cow-peas he found that the plantsremoved from 17 to 60 per cent.of the phosphoric acid soluble innitric acid, and he concluded that a relation was indicated betweenthe phosphoric acid so dissolved and the needs of the soil.Potas?& and Soda.M. Berthelot,3 by treating wood ashes with 1 per cent. hydro-chloric acid and then washing with water, found that from 5 to 6per cent. of the total potassium was retained as organic compounds.He also ascertained the presence of organic potassium compouqdsin living vegetable tissues ; if digested with potassium acetatesolution the insoluble organic matter fixed a certain amount ofpotassium, and if solution of calcium acetate was used calcium wasfixed and potassium liberated.The influence of potassium manures on the quality of barleyhas been studied by several observers, and, among them, 0.Reimerhas noticed that, whilst potash increase5 the yield of grain,the amount of proteins is in no way reduced. K. As64 obtained thesame increase of grain with barley by using potassium chloride.finding, however, that potassium sulphate was more favourableto straw production; potassium, silicate was, on the whole, the bestform, and the new potassium manure " martellin " gave good resultsin this connexion. Sulphate of potash and kainite have beencompared as potassium manures for potatoes a t the WoburnExperimental Farm,5 the results of 1905 confirming thoseJ. Amer. Chcnt. Soc., 1906, 28, 823.Compt. read., 1905, 141, 793, 1182.Chem. Centr., 1906, i, 154.Bull. Coll.Agr. Tckyd, 1906, 7, 67.J. Roy, dgric. SOC., 1906, 67, 305AGRICULTURAL CHEMISTRY AKD VEGETABLE PHYSIOLOGY. 27 7previously recorded to the effect that sulphate of potashis, on a light, sandy loam, a preferable form to kainite,1 cwt. per acre of the former and 4 cwt. per acre of thelatter being respectively used. This proved to be alike the casewhether nitrate of soda or sulphate of ammonia was used as thenitrogenous manure. The relations of potassium and sodium saltsin soils and as supplied in manures have occupied considerableattention, and especially in connexion with sugar-cane and sugar-beet cultivation. J. F. Breazeale 1 grew wheat plants in solutionscontaining all necessary elements except potassium and sodium,then removing the plants to solutions with full nutrient constituentsand ascertaining the amounts of the constituents taken up.I n thisway it was found that potassium was taken up much more vigorouslywhen sodium had been left out in the first period than when it waspresent all the time. Similarly, by taking beet plants which hadbeen first grown in soil to which potassium or sodium salts had beengiven as manures, and then removing them to solutions containingfull nutrient matters, the plants to which no potassium had beengiven to the soil for some years took up potassium more vigorcruslythan where sodium had been applied. J. Urban2 has studied therelation of potassium and sodium salts in the case of sugar-beet.When sodium nitrate alone was used on a sandy humus soil therewas abnormal development of leaf, and though the total ash (leafand root) was much the same as in normal beets, it contained avery high proportion of sodium salts, much exceeding that ofthe potassium salts.So, although sodium may replace potassium inthe plant’s composition, it is a t the expense of proper root develop-ment and consequently of sugar-production. Urban attributes theabnormal composition to the great preponderance of nitrogen overpotash, the ratio of K,O to N having been 1 : 3.1, whereas heconsiders that the best ratio for sugar production is 1 : 1.Biliccc.A. D. Hall and C. G. Morrison3 have examined again the partplayed by silica in the nutrition of plants, and, while confirmingprevious conclusions as to its not being a necessary constituent ofplant food, have brought out interesting points as regards thefunctions which it exercises, and mainly in reference to the takingup of phosphoric acid.The observations have been made in respectof some of the permanent grass experiments in Rothamsted Parkand the permanent barley plots in Hoos Field. On the grass landJ. Amer. Chem. Soc., 1906, 28, 1013.Zeit. Zuckerixd. Bohni, 1906, 30, 397.8 PTOC. Roy. SOC., 1906, 77, B, 455278 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTKY.the use of sodium silicate along with mineral manures and ammo-nium salts gives, over 42 years, an annual increase of 10 per cent. inthe crop above that of a similarly manured plot without sodiumsilicate. An explanation of this is supplied by the barley plots,where sodium silicate has been employed with and withoutphosphates.Its use causes earlier formation of the grain andhastens the ripening of the crop. The omission of bot,h silica andphosphoric acid results in a poor crop (27 to 28 bushels per acre),but if sodium silicate is applied without phosphoric acid the cropis increased to 34 to 36 bushels, and more phosphoric acid is foundin the ash of the grain, although there is less in the ash of thestraw. Silica would thus appear to be able partly to replacephosphoric acid, the effect of it being that it imparts a stimuluswhich enables more phosphoric acid to be taken up by the plantfrom the soil. Barley plants were examined a t different stages ofgrowth, and it was found that, in general, only 9 per cent.ofthe silica reaches the grain in the early stages, and that, whereasordinarily the dry matter reaches its maximum about July 18-25,if no silica or phosphoric acid is supplied the dry matter doesnot reach its maximum until August 8. A series of water-culturesfurther confirmed these results and showed that while silica cannotreplace phosphoric acid it may stiniulate the plant to take upmore. And, lastly, by extracting the soil of the different plots withhydrochloric and citric acid respectively i t was shown that thesodium silicate has no direct solvent action on the soil phosphates.The ( I Rurei- ” Coizstituents of Plants and Soils.(a) Manganese.N. Passerinil grew lupins (Lupinus albus) in a soil containing0.068 per cent.of manganese, and examined the different parts ofthe plant in regard to their contents of manganese. The leavescontained 8.26 per cent. of ash, and of this ash 12.43 per cent.consisted of manganese reckoned as Mn,O,; the seed pods con-tained the next highest proportion, namely, 6 to 7 per cent. of theash (total 3.5 per cent.), and then the stems and the seeds, theroots lastly having still less. I n pot experiments, with and withoutaddition of manganese carbonate, the soil containing only 0.0002per cent of manganese, the dry matter contained 0.0095 of man-ganese when none was added and 0.0636 per cent. when it was givenas manure. T. Katayama2 showed that manganese has a stimula-tive effect on oats, barley, rice, &c., although this is not so greatBol.1st. dgmr. Scandicei, 1905, [ii], 6, 3.Bull. Coll. Agric. TGkyd, 1906, 7, 91AGRICULTURAL CHEMlSTRY AND VEGETABLE PHYSIOLOGY. ‘279as on leguminous plants. Using manganous sulphate on peas inquantity to supply 0.015 per cent. manganous sulphate to the soil,the increase was 50 per cent. in the yield of &raw and 25 percent. in that of the seeds, whereas with barley the total increasewas only 10 per cent. Quantities much exceeding the above tendedto decrease the yield. G. Salomonel confirms these results as tothe beneficial influence of a certain quantity of manganese and thetonic action_ of large amounts, and points out that the manganicsalts are more tonic than the nianganous, rnanganic acid especiallybeing hurtful.M. Nagaoka 2 obtained confirmation of formerexperiments, getting with rice a gain of 15 per cent. when usingmanganese sulphate up to 100 kilos. per hectare.(b) Copper.A. Stutzer 3 grew Trifolium pannonicum in pots with sand, gardensoil, calcium carbonate, and mineral manures. He added t o two ofthem finely-divided copper (1 gram and 10 grams) and to other twopowdered copper oxide in the same amounts, other pots receivingno copper. I n only one instance-when 10 grams of copper oxidewere used-was any injury noticeable, but here the plants eitherfailed or remained very small. Examination of the plants failedt o detect copper in them, even in the roots. W. W. Skinner hasexamined the effect on vegetation of irrigation water containingcopper salts derived from the waste products of mining operationsOne part of copper in, 800,000 has been found to be fatal t o thegrowth of corn, and as little as one part in 700 millions willretard the growth of wheat seedlings.The author concludes that 1part of copper per million is enough to condemn a water for use forirrigation purposes. He has further tested the general belief thatthe presence of carbonates and bicarbonates, by rendering copperinsoluble, will remove any danger of injury, and finds that it isnot justified, inasmuch as a considerable amount of copper remainsin solution, even if carbonates and bicarbonates are present inquantity. E. BrBa15 treated seeds with a solution prepared byboiling starch in 1 litre of 0.3 per cent.of copper sulphate solution.The seeds were soaked for twenty hours and then left to dry. Theirweight was increased somewhat, their germination was improved,and, besides the freedom from “smut ” and other diseases, the cropwas somewhat increased. (See also under mercury.)Chem. Centr., 1906, ii, 532.Bull. Co71. Ayric. Takyii, 1906, 7, 77.Lnndw. Verszcchs-Stut., 1906, 65, 285.Compt. ?-end., 1906, 142, 904.‘ J. AWIW. C ~ W I Z . +%c., 1906, 28, 361280 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.(c) Alwminium.H. Micheels and P. de Heen 1 investigated the effect of aluminiumsalts on the germination of wheat; with the result that, whilst theyfind alumina or kaolin to be beneficial, the addition of solublealuminium salts is proved to be injurious.On seedlings themselvesit would seem, from the work of H. D. House and W. J. Gies,2 thatthe injurious effect is dependent entirely on the extent of theconcentration.(d) Mercury and Silver.T. Bokorny 3 finds that a l p are killed by salts of copper, mercury,and silver if the concentration is 1 to 1 million. All other metalsrequire to be in more concentrated solution than this to do anyinjury.(e) lodine.S. Uchiyama,4 by using small amounts of potassium iodide,increased the yield of sesamurn and spinach. With sesamum heobtained an increase of 16 per cent. by using 124 grams ofpotassium iodide per hectare. This was confirmed by a fieldexperiment, and the matter has some interest owing to the commonpractice of using seaweed as manure where available.(f) Fluorine.Experiments of K.As55 with both soil and water culture seemto point to precipitated calcium fluoride as possessing some stimulat-ing action. This cannot, however, be due to hydrogen fluoride,inasmuch as this is not liberated by carbon dioxide and weak acids.AvaiJability of Soil Coiutituents.J. Konig, J. Hasenbaumer, and C. Coppenrath,6 in seeking fora method of determining the available constituents of soils, haveobtained the best results by placing the soil in a linen bag insidea copper vessel and heating the whole with water for three hoursunder a pressure of four atmospheres. The solution is thenfiltered, evaporated down, and the different constituentsestimated.Bull. Acad.roy. Be7g., 1905, 520.Proc. Amer. Physiol. S’oe., 1905, xix-xx.Chem. Zeit., 1905, 29, 1201.Bull. Imp. Centr. Agric. Exp. Stn. Japan, 1906, 1, 35.Bull. Coll. Agr. TCky6, 1906, 7, 85.Lnndzc?. Vcmmhs-Stat., 1906, 63, 471AGRICULTURAL CHEMISTRP AND VEGETABLE PHYSIOLOGY. 281Oxidation in Soils.E. J. Russell1 has continued his work on the rate of oxidationin soils and the relation this bears to their productiveness.Oxidation is due mainly, but not exclusively, to the action ofmicroorganisms, as it still goes on when the soil has been sterilisedby heating or by treatment with mercuric chloride or other re-agents. The rate of oxidation is, however, much reduced. More-over, i t does not depend on the amount of organic matter present;up to a point the presence of moisture helps; similarly, the pre-sence of calcium carbonate o r of a carbohydrate aids the rate.With partial sterilisation the rate of oxidation also increases, andthis would lead to the belief that, whilst the work of some organismsis checked, the activity of others may be favourably influenced bypartial sterilisation. This only takes place, however, underaerobic conditions, as in arable soils, but not in pasture soils,where the conditions are anaerobic.C. Schulze 2 has investigated the effect of sterilisation of soils, andfinds that whilst some substances injurious to plants are formed, thesoil constituents generally are made more available.Theresult as regards the plant will depend on the predominance of oneor the other influence.It is clear from the foregoing and the observations of others, thatthere remains still a great deal of work to be done in ascertainingexactly what changes take place in the bacterial and chemical con-ditions of different soils as well as in their physical relations,through the employment of processes of sterilisation, partial orcomplete, and that the results obtained with sterilised soils haveto be taken in conjunction with the various changes thereby pro-duced.Germination.P. Becquere13 has studied the action of carbon dioxide on seedswhich have been decorticated or perforated.When the seeds arein their naturally dry condition they will not be injured,though kept in an atmosphere of carbon dioxide; but if they arepreviously immersed in water for a, quarter of an hour they willbe all killed by exposing them to an atmosphere of carbon dioxide.0. Kamberskf? by placing seeds for forty-eight hours in contactwith a nutritive solution containing ammonium nitrate, potassiumBrit.Assoc. Reports (Section B), York, 1906.Landw. Versuchs-Stat., 1906, 65, 137.Conzpt. rend., 1906, 142, 843.Chem. Ceittr., 1906, i, 570282 ANXUAL REPORTS ON THE PROGRESS OF CHEMISTRY.nitrate, di-ammonium hydrogen phosphate, and di-sodium hydro-gen phosphate (Iszleib's solution), found that germination was re-tarded and a lower germination percentage obtained. A. Stutzerhas shown also that nitrates generally act injuriously on germinat-ing seeds; beet plants are very sensitive to nitrates, but red cloverresists their action.The behaviour of cyanamide towards germin-ating seeds has already been dealt with (page 261), but Bartsch 2 hasshown that, while the germination of mustard, oats, and barley isaffected when the seeds are sown a t the time of applying the cyan-amide, and will be still noticeable if a week intervenes, yet, if aninterval of three weeks is allowed between the application of thecyanamide and the sowing of the seed no injurious action willfollow.H. Micheels and P. de Heen3 have further found that ozonehas an injurious effect on seedlings, the roots in particular beingattacked.A ssimila tion.3'. L. Usher and J. 13. Priestley4 show that, in presence ofchlorophyll and under suitable conditions, aqueous carbon dioxideis decomposed into formaldehyde and hydrogen peroxide, formicacid being produced as an intermediate substance.This goes on in-dependently of any enzyme action, and depends solely on the properphysical and chemical conditions being present. It is possible toreconstruct this process outside the green plant. The formaldehydeand hydrogen peroxide rapidly undergo change,- and are not foundin the assimilating leaf under ordinary conditions. Working onthe leaves of Acer Negundo, B. Schultze ascertained that the in-crease in weight of the leaves, under the influence of light, was notdue only to the assimilation of starch, but also to that of proteins.But while carbon assimilation went on the production of proteinsgradually diminished.Ueuelopment.By growing green plants without carbon dioxide in an artificialsoil containing amides, J.LeGvre' showed that the dry matter ofthe plants rapidly increases, the growth being quite normal. I nabsence of light the plants failed altogether, although amides werepresent. The results go to show that the carbon dioxide of thesoil is not absorbed by the roots, or, a t least, is not utilised bythem.The oxidising power of living cells on the surface of roots wasJ. Lnndw., 1906, 54, 125.Bull, Acad. roy. Belg., 1906, 364.Baed. Centr., 1906, 35, 35.C?mn. Centr., 1906, i, 585, .I Proc. Roy. Soc., 1906, 78, E, 318.ti Compt. rend., 1905, 141 664, 834, 1035AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 283shown by experiments of M. Raciborski,l who grew plants in solu-tions which do not affect the life of the roots’ cells, but which, onoxidation, yield products either themselves coloured or capable ofcolouring suitable reagents.This power is, however, a purely localone, and is confined to the absorbent surfaces of the roots, beingstrongest near the root, hairs.The influence of light on the development of proteins in thewheat grain has been studied by J. Dumont.2 The, accumulationwas greatest under the influence of brown light, then under green,blue, and red light successively. I n the absence of light, A.Kiesel3 found not only asparagine to increase, but also otheramino-acids, especially leucine, and certain bases, such as arginine,not found in healthy plants.H. Schjerning,” in investigating the formation and changes inthe protein substances of barley during growth, ripening, and stor-ing, concludes that barley has attained its full maturity when thesoluble carbohydrates are converted into insoluble ones and thesoluble into insoluble proteins.H. T. Brown, F. Escombe, A.McMullen, and J. H. Millar5 have observed the migration ofnitrogen in barley from the endosperm t o the embryo during ger-mination. It was noticed by them that if the embryo was removedand allowed to grow in water or in a carbohydrate medium the rootexhibited a restricted development, and the embryo seemed tobe suffering from nitrogenous starvation. This nitrogen it would,in the ordinary course, derive from the endospem. The observa-tion was continued to barley undergoing the malting process, thenitrogen being determined a t various intervals in the endosperm,embryo, rootlets, &c.It was found that after nine days’ germi-nation 35 per cent. of the nitrogen originally present in theendosperm had migrated to the embryo, and must in so doinghave been converted from the insoluble protein form into solubleand diffusible compounds.The same authors continued their studies on the nitrogenousconstituents of malt that are soluble in cold water, with a viewt o ascertaining how far the quality of barley depends on these.An examination of the sprouted ‘‘ culms ” led to the identificationin them of asparagine, allantoin, betaine, and choline. The water-soluble uncoagulable nitrogens of malt have now been dividedby the authors into six classes of bodies, and their approximatepercentages have been also worked out.They consist of theCompt. mad., 1905, 141, 686. Bull. Acad. Sci. Cyacow, 1905, 338.Zcit. physio?. Chena., 1906, 49, 12.Z’rav. Laborat. Carlsbery, 1906, 6, 229.Trans. Gz6inness Research Lab., 1906, 1, part 2, 149, 169, 175, 238, 242, 284,3382% ANNUAL 13EPORl'S ON THE PROGRESS OF CHEMISTRY.following : -ammonia-nitrogen, 3.5 per cent ; malt-albumose nitro-gen, 20 per cent.; malt-peptone nitrogen, 31 per cent.; amideand amino-nitrogen, 8.5 per cent.; nitrogen due to organic bases,4 per cent.; uninvestigated bodies, 33 per cent. The conclusionis also arrived a t that, from the chemical point of view, no distinc-tion can be drawn between animal and plant proteins.The action of light on the transformation of sugars in youngplants has been studied by W.Lubimenkol in connexion withthe embryos of Pinus pinea. When these were exposed to lightof varying intensity in sterilised solutions of sucrose, dextrose,maltose, lactose, galactose, and arabinose, it was found that underthe action of the light the absorption of sucrose, dextrose, andarabinose went on, but with varying activity, diminishing as theintensity of the light increased. The light had no effect on theassimilation of maltose, lactose, laevulose or galactose.According to G. A. Calabresi 2 pentosans would seem to be formedin young plants, but t o decrease later on. I n sugar-beet, whenpentosans are high in amount sucrose is low, and, generally, inplants the pentosans are higher when nutritive constituents arelow.W.Palladin and S. Kostytschew 3 show that during the anaerobicrespiration of seeds and .seedlings a consitderable amount of alcoholis formed. Both living and frozen seeds have been experimentedwith; with frozen peas alcohol is formed whether oxygen be presentor not, but with living peas the formation of alcohol only goeson in absence of oxygen, Acetone is also found to be formedduring anaerobic respiration.W. D. Bigelow, H. C. Gore, and B. J. Howard4 have investigatedthe changes which go on during ripening in certain plants con-taining a good deal of tannin. They find that the tannin disappearsduring the ripening, passing possibly into insoluble forms. Micro-scopical examination shows that a t first the tannin is fairly uni-formly distributed through the fruit, but that, as ripening proceeds,it becomes deposited in insoluble form in special cells.&f ici-o-orgunisnts.N. L.Sohngen5 was led, by the consideration that methane,although so abundantly produced, is yet found only in traces irrthe atmosphere, t o search for organisms which were capable offeeding on the hydrocarbon. He found that if a culture-liquidCompt. re?td., 1906, 143, 516. Chcnz. Cevtr., 1906, ii, 964.J. A m e r . Chesn. Soc., 1906, 28, 688,Proc. K. Aknd. Wetcnsch. Amsterdam, 1905, 8, 327,3 Zeit. physiol. Chem., 1906, 48, 214BGltICUL'l'UltAL CHEMISTRY AND VEGETABT,E PHYSIOJAIGY.285was iniprcgnated with gardeii soil, sewage or the like, in an atliio-sphere of methane and oxygen at 38O, a slimy, pink film formedon the surface, and that this consisted of short, rod-like bacteria,which he named Bacillus metjznnicics. Within a week the methaneis nearly all absorbed, being thus utilised as a source of carbon.H. Kaserer,l working on the same subject, shows that the presenceof hydrogen and methane hinders the production of nitrites fromammonium salts. If there is a plentiful aeration, both oxidation ofhydrogen and nitrification may go on together, but, if aerationbe imperfect, nitrification will only begin after all the hydrogenhas been oxidised. V. Omeliansky2 finds that methane is producedby fermentation from cellulose, gelatin, peptone, and many othersubstances, and thinks it probable that all soils that have organicmatter will produce methane. Accordingly, i t is not possible tosay, from the mere fact of methane being produced, what thenature of the organic matter decomposed is.From the excrementsof pigeons C:. Ulpiani and M. Cingolani have isolated a micro-organism which decomposes guanine into carbamide, guanidine, andcarbon dioxide.In the fermentation of sugar-cane juice C. A. Browne4 hasnoticed that a frequent fermentation is that resulting in the for-mation of cellulose. This he has investigated and finds i t to beaerobic, being due probably to Bacterium xylintcm. From canejuice the amount of cellulose thus formed may be 7 per cent. oft'he total sugar fermented.The effect of light on bacteria has been investigated by H.'Phiele and K.Wolf.5 While the bacteria were destroyed quicklyby strong light, if the light was filtered through solutions ofnitrates or oxalic acid i t had no effect on the bacteria; if passedthrough disodium phosphate and potassium thiocyanate solutionsenough active light passed through to kill the bacteria. Fromthis the active bactericidal region was fixed. Light filtered througha piece of blue rock-salt crystal (the ultra-violet rays alone passingthrough) rapidly destroyed the bacteria.has observed the action of carbon dioxide a t highpressure on the bacteria contained in river water and in milk.Under a pressure of 50 atmospheres the bacteria are killed entirelyin twenty-four hours in the case of river water.But with milk thebacteria are not entirely destroyed, even at a temperature of 50°,although the casein is coagulated and separates out.W. HoffmannI Centr. Bnkt. Pw., 1905, ii, 15, 573. ' Atti 22. Accnd. Lincei, 1905, 14, ii, 59G.Ibid., 1906. ii, 15, 673.J. Amr. Chcm. Xnc., 1906, 28, 453.Arch. Hygiene, 1906, 57, 29.flkcth h t . C0ng.f. Appl. Chcm., Chew?,. Zeit., 1906, 30, 422286 ANNUAL REPORTS ON THE PROGRESS OP CHEMISTRY.Bnzynm,J. Stoklasa 1 has isolated several enzymes from beetroot. rheaehe identified as oxydases, invertase and glycolytic enzymes. Thelatter set up alcoholic fermentation in dextrose solutions, alcoholand carbon dioxide, as well as small quantities of acetic and lacticacids being produced.Formic acid has also been found as aproduct, and the author hints that this may give rise to thehydrogen which is evolved together with carbon dioxide, and mayplay a part in the assimilation of carbon in the chlorophyll cells,in which process formaldehyde and water are formed. The glyco-lytic enzymes are given as (a) lactolase, (b) alcoholase, (c) acetolase( d ) formilase, these causing the production of lactic acid, alcohol,acetic acid, and formic acid respectively.C. A. Brownez finds invertase in the green tops of sugar-cane,and notes that if the tops are removed when the cane is cut thediffusion of the enzyme into the stalk is prevented, and thereis less loss of sucrose. The darkening which sugar-cane juiceundergoes after expression is due to oxydases.GZwcosides and Cyanogenesis.Several investigators have continued their inquiries into thepresence in various plants of certain glucosides which, under theaction of an enzyme, gives rise t o the production of hydrocyanicacid.Numerous plants other than Phaseolus Zunntus (with whichDunstan and Henry worked) have been found to contain glucosidesof this character, and the yield of hydrocyanic acid has been quan-titatively recorded. W. R. Dunstan, T. A. Henry, and S. J. M.Auld3 find phaseolunatin in small amount in flax seed, and anenzyme of the emulsin type similar to that in Phaseolus Zmatus.They also find a glucoside and an enzyme similar to, if not identicalwith, those of I’haseoZus Zunatus, in the root of bitter cassava.L.Guignard 4 also establishes the presence of cyanogenetic glucosides inmany of the Rosaceae. He has further determined the amount ofhydrocyanic acid obtained from the ground beans of PhaseoZusZunatus, obtaining 0.052 to 0.102 per cent. with Java beans, butconsiderably less with Burmah, Madagascar, and Provence varieties.Further, he does not find, as others have done, that the whitecultivated beans are quite free froin hydrocyanic acid, and, inSixth 1nt. Congr. Appl. Cheva., Chem Zeit., 1906, 30, 422.J. Amer. Chem. sbc., 1906, 28, 453.3 Proc. Boy. Soc., 1906, 78, B, 145 and 152.-I Cow@. rmul., 1 Tf06, 143, 451, and 142, 545AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSlOLOGY. 287examining white beans that occur among Java beans he obtainsjust as much hydrocyanic acid from them as from coloured beans.He states that the poisonous properties are not removed on boiling,as this only destroys the enzyme and not the glucoside.R. R.Tatloclr and R. T. Thornson1 obtained from Java beans from 0.027to 0.137 per cent. of hydrocyanic acid. They examined seearatelythe variously coloured beans, but could arrive a t no generalisationas to the relation of colour to yield of acid. Discussing the state-ment that has been made that cyanogen is in the husk and notin the kernel, they state that this is not the case, but that thekernel has ten times as much as the husk. They examined severaldifferent varieties of beans, but only found hydrocyanic acid tobe produced from Java beans and Rangoon beans.On steepingthe beans in warm water and boiling them thoroughly, an originalpercentage of 0.009 of hydrocyanic acid falls to 0.002 and theenzyme is destroyed; in cold water the cyanogenetic glucoside isdecomposed.Kohn-Abrest 2 disagrees with the conclusion of Dunstan andHenry that there is one cyanogenetic glucoside in Phaseolus Zunatus,and considers that many are present. J. TV. Leather3 examin-ing a sample of sorghum (Sorghum vulgare) fodder whichhad proved harmful to cattle in India, found it to be immatureand t o contain 1-28 grains of hydrocyanic acid per lb. of greenstuff. The largest quantity was found in the leaves. Ilf left tomature the plant contained no hydrocyanic acid, but drying theimmature fodder in the sun produced no change in quantity.Theglucoside present was dhztrrin, as previously recognised by Dunstanand Henry. Leather confirms the presence of hydrocyanic acidin Rangoon beans and immature linseed.Foods and Feeding.K. Farnsteiner, K. Lendrich, and P. Buttenberg 4 examined lardsobtained from pigs that had been fed on potatoes, maize meal,cotton-seed meal, &c., with the result that a portion of the oilderived from the foods was shown to be deposited in the bodyfat of the animal. This was especiaIly marked in the case of maizemeal. T'he decomposition of foods in the absence of air has beeninvestigated by J. Konig, A. Spieckermann, and H. Kuttenkeuler?who find it to be practically the same in nature as when oxygenis present, although the products are different in quantity.Thegreatest loss is in the non-nitrogenous extract, although when airAnalyst, 1906, 31, 249.Agric. J . of India, 1906, 1, 220.]bid., 1906, 11, 177.Compt. rend., 1906, 143, 182.Zeit. Ndw. Geizussnz., 1906, 11, 1288 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTKT.is absent tliere is comparatively little loss of dry matter. The lossof nitrogen is very small, the proteins decomposing only slightly.The foods, in absence of air, tend to become strongly acid, but donot alter their appearance.E. Schulze,l taking potatoes, as containing a relatively largeamount-of asparagine, shows that this is converted, when consumedby animals, into amino-acids and then into succinic or malic acids,which have no value for fat production in the case of carnivorousanimals.0. Kellner,2 however, from experiments with sheep, con-cludes that asparagine may indirectly economise proteins in thecase of ruminants. Laetic acid he finds to be simply oxidised andto produce heat only.J. Konig3 has attempted to separate the various constituentsmaking up the so-called ‘( crude fibre ” in foods, and gives methodsof ascertaining the cellulose, lignin, and cutin. Lignin is separatedby digestion in the cold with hydrogen peroxide in presence ofaqueous ammonia, it being converted by this treatment into solubleproducts. Cellulose is next separated from cutin by treatment withcopper-ammonium hydroxide, it being thereby dissolved, leavingthe cutin undissolved. As the plant gets older the lignin increasesmore than the cellulose, and, broqdly speaking, the higher thepercentage of lignin and cutin the lower is the digestibility ofthe crude fibre.J.Hendrick,4 following up the work of T. B. Wood, R. A. Berry,and S. H. Collins (see AnnuaE Report, 1905, 264) has obtainedsimilar results for yellow swedes and turnips grown in the N.E.of Scotland. He finds marked variations according as the rootsare grown in different parts of the country, and emphasises (asdid the authors named) the necessity of taking a large numberof roots (100 suggested) in order to get satisfactory results. Hehas made the attempt to arrive at the value of the roots bycomparing the ratio of the soluble to the insoluble matter in thesolid matter of the roots.Crops.(a) ( ( Strength ’’ in Wheat.This subject has been further attacked both from the chemicaland the biological side.A. D. Hall5 has examined critically thedifferent constituents of the grain, with the view of finding outto which of them the quality of “strength” may be due. Buthe does not find any consistent correspondence between the pre-J, Landw., 1906, 54, 65.T7.ans. High. and Agric. SOC. of ScotEand, 1906.h?ep, Home-grown, ?.‘heat Committee (Mir’lers’ Gazette), 1906.B e d . Centr., 1906, 35, 45.3 Zeit. Nahr. Genussm., 1906, 12, 385AGRICULTURAL CHEhIISTltY AND VEGETABLE PHYSIOLOGY. 289dominance of any of these and the possession of “strength,” andis unable to go beyond the general statement that nitrogen may,as a rule, be taken as a test of “strength,” whilst the carbohydratematters do not contribute t o it.Hall finds that different stagesof ripeness do not determine “strength,” inasmuch as a crop cutdead ripe may be just as “strong” as one cut green. Nor does itfollow that a highly nitrogenous grain is of necessity a ‘‘ strong ’’one; some were, indeed,*the weakest of all from a baker’s point ofview. But it was observed that these, i f kept, became changed;their physical structure seemed to be altered, and they were thenincreased in Hall remarks on the observed “ acidity ”of flour, and finds that this is due t o the presence of a littlepotassiuni phosphate.Meanwhile the subject has been investigated further from thebiological side by R.H. Biffen 1 and with more hopeful prospects.Biffen eliniinates climatic conditions as having little or no bearingon the question, and attributes the whole to the matter of“ selection,” and looks t o the producing of “ hybrids ” to obtainthe desired quality of “strength ” combined with good yield.strength.”(b) Quality in Barley.The results obtained a t the Woburn Experimental Farm for theyears 1898-1904 on the influence of manures as affecting theyield and quality of barley have been collected and summarised?and, in general, confirm the results obtained a t the RothamstedExperimental Station. The main points as regards quality arethat this was improved by mineral manuring (superphosphate withsulphates of potash, soda, and magnesia), that farmyard manuregave very variable results, and that the best ones were obtainedwith mineral manures in combination with ammonium salts ornitrate of soda used in moderate quantities.Nitrate of soda byitself or used in excess gave a low “ weight per bushel ” and much“ tail ” corn.Industries.(a) Sugar.A considerable impulse has been given of late to the growingof sugar, more particularly of cane-sugar, and with this has comean extension of inquiry into points connected with the cultivationof the crop and the securing of the produce.H. W. Wiley3 summarises his observations on the influence ofenvironment on sugar production in the beet. Temperature heJ. Agric. Sci., 1907, 2, 1. J. Fed. Iitst. Brcwiity, 1906, 12, 408.3 U.S.A. Dept. Agric.Bid/., 1905, 96.VOL. 111. 290 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.finds to be of the greatest importance; there is little relationbetween sunshine and sugar yield, but longer daylight means moresugar; rainfall only incident,ally affects the output, but a smallyield of crop means an increased sugar percentage ; lastly, thejuice becomes purer as the percentage of sugar rises.find that sucrose is not uniformly distributedthrough the beetroot; some cells contain only water and salts,and the water is that termed by Scheibler ‘ I colloidal” water.Hence the difficulty in obtaining representative samples. Completediffusion of the juices only takes place when the pulp is finelyground and digested with cold water or hot alcohol.K. Andrlik and J./Urban2 have examined the ‘(objectionable”nitrogenous constituents in beet-root juice, and find that theseare not amide or ammonium compounds. About 70 per cent. ofthe whole of the injurious matters originally present in the rootare found in the juice. This quantity is increased by storage ofthe roots, probably owing to a breaking-down of the proteins.Experiments in sugar-beet growing in the eastern counties ofEngland3 have given in 1906 an average yield per acre of fourteentom of roots, containing 16 per centl. of sugar, with a coefficient ofpurity 87. This yield, however, is not sufficient, in the cir-cumstances of this country, t o “pay” for the manufacture ofsugar. W. D. Horn04 has inquired into the deterioration whichsugar-cane undergoes when the canes have been cut.On each ofsix successive days he cut off pieces from canes, and noticed thatthe deterioration was greater with the top part of the cane thanthe bottom, but there was also a deterioration due t o keeping.Thus, starting with 16.97 per cent. of sucrose on the first day, bythe time the fifth day was reached the sucrose had fallen to 11.86per cent.; in the first day there was a deterioration of 0.25 percent., in the next two of 1.75 per cent., and in the next two ofnearly 4 per cent. F. Watts and H. A. Tempany5 observed thechanges which sugar-cane juice undergoes when allowed to fermentspontaneously; the juice becomes acid and of a yellow colour,a dark scum rising to the surface; alcoholic fermentation sets in,carbon dioxide is given off, and quite 8 per cent.of alcohol isformed. Then acidification of the alcohol ensues, ‘( cane sugar ”being obtained. The acidification of the juice was found to be pro-duced by oxidation of the sugar by bacterial agency; this could beprevented by the addition of 2 per cent. of phenol t o the juice.1 Ez~ll. Assoe. Chim. Suer. Did., 1906, 24, 615.Zeit. Z t ~ k e ~ i i i d . Biihm., 1906, 30, 282.Bep. E. Sz~foZk CItctnzbe.1. of Aqriczrlt?s?*e, 1907.J. SOC. C?cewt. Ind., 1906, 25, 161.ICTest Ind, Bzhll., 1906, 6, 387.H. and L. PelleAGRICULTURAL CHEMIS‘L’RY AND VEGETABLE PHYSIOLOGY. 291C. A. Browne,l jun., attributes the gradual inversion of thesucrose after the cane has been cut to the invertase which existsin the green tops of the cane. He has investigated the differentfermentations, aerobic and anaerobic, which take place in thejuice.Among the former are those due t o Bacterium x y l k u m andto citromyces, and among the latter that produced by Leuconostoc,a viscous fermentation.H. Pellet2 refers to the suggestion of adding invert-sugar tomolasses to aid crystallisation of the la,tter, since sucrose is lesssoluble in invert-sugar solution than in water, but he shows thatthis is not an advantage, inasmuch as the invert-sugar brings aboutthe retention of more water, and this more than neutralises thebenefit that might accrue.(b) Tea.H. H. Mann3 in a paper entitled “The Fermentation of Tea”(part I.) gives a valuable contribution to our scientific knowledgeof the manufacture of tea.Indeed, it may be taken, in conjunc-tion with his earlier paper, (‘ The Ferment of the Tea Leaf ” (seeAnnual Report, 1904, 215) as supplying the first clear exposition ofthe scientific side of the subject. Moreover, it affords a most usefulexample of how the study of the underlying chemical principlescan be made t o contribute to the practical well-being of an impor-tant industry. Mann had shown in his earIier paper that thefermentatlion is due t o an enzyme of the nature of an oxydase,and that the, quantity in which it is present is an indicationof the quality of the tea. He now goes on to consider the variousconstituents of the leaf, t o observe the changes in them during thedifferent processes of withering, rolling, &c., and to see in what waythese affect the value of tea as a finished product.Living organ-isms, i t is shown, do not take part in the fermentation, and theirexclusion as far as possible from the fermenting room should besecured. The constituents studied in detail are (1) essential oil,(2) caffeine (or theine), (3) tannin. The quantity of essential oilpresent is very small; it is driven off a t a high temperature, andchanges into a resin on exposure t o air; it seems t o be one of thechief factors in determining flavour in tea. Caffeine exists to theextent of 3 to 5 per cent. Its presence has no bearing on themarket value of tea, although it may have on its medical value.Mann next deals very fully with the matter of tannin, and showsthat, contrary to general opinion, this is not an objectionablefeature, but that there is a close connexion between the quantityJ.Amcr. Chcnt. SOC., 1906, 28, 453.BdE. Assoc. Clzim. Xucr. nist., 1906, 24, G69.3 Indian Tea Assoc., 1906, 1 and 2.u 292 A N N U L REPORTS ON THE PROGRESS OF CHEMISTRY.of tannin that can be removed in a five iiiinutes’ extraction withboiling water and the value of tea in the market. Tannin, as i toccurs in the leaf, seems t o be combined with sugar, and thetannin undergoes oxidation during fermentation of the leaf, throughthe presence of the oxidising enzyme. The oxidised tannin willthen combine with the caffeine and other materials to form freshsubstances which are mostly insoluble in water. During the processof rolling, the soluble matter in the leaf is reduced, and so isthe amount of soluble tannin. Mann has further noticed theinfluence of light on the fermentation of tea, and finds that, whilstfermentation proceeds rather less rapidly with a. blue light, thereis no change in the percentage of tannin, but only in that of totalsoluble matter. What is of importance, however, is thickness ofspreading, and this should not exceed 1& inches in depth. Experi-ments in green-ma,nuring for tea established the usefulness ofleguminous plants, especially sau (.4 Zbizzia stipulntci).(c) Tobacco.J. Toth1 has set oat’ a new method of determining the orgauicacids in tobacco. Expressing these in terms of oxalic acid, he findsthe quantity to range from 3’6 t o 8.7 per cent., and, after trialswith 32 different samples, concluded that bad-burning tobacco wasthat which contained the most organic acids, and tiice vers&.(d) CinclL ona.D. Howard2 shows that by careful selection and cultivation theamount of quinine alkaloid in cinchona bark has been raised inJava from 4 per cent. to 10 per cent.(e) Cassava.H. H. Cousins3 has esbimated the amounts of starch obtainedat different periods of growth from 23 varieties of cassava, grownin Jamaica. He gives the produce of starch per one-tenth acreas follows:-At 1 2 months, -34 tons; a t 15 months, 54 tons; at21 months, 7$ tons.(f) Eggs.J. Hendrick4 has examined the composition of eggs preservedby the use of “wateryglass”; he finds that there is a slowdeposition of silica in the shell, but that there is no change inthe composition of the interior portion.Clwwt. Zcit., 1906, 30, 57. 2 J. xoc. c r ~ ~ ~ l t . b L d . , 1906, 25, 97.3 Jaiizaiccc Gaxtlc, Nov. 22iid, 1906, 330. J. Agric. Sci., 190T, 2, 100AORTCULTURAL CHEMISTRY AND VEGErABJ,E PHYSIOLOGY. 293H. D. Richniond 1 gives his annual statement of the compositionof milk, as obtained from good dairy farms supplying milk dailyto London, during 1905. The figures are taken from an averageof nearly 15,000 samples, and are as follows:-Fat, 3.73 per cent;solids-not-fat, 8.97 per cent.; total solids, 12.70 per cent.; sp.gr., 1.0323. The average percentage of fat of the morning milkalone was 3.54; of the evening milk, 3.91. These figures differbut very slightly from those of 1904.A. Morgen, C. Beger, and G. Fingerling2 have investigated, over aperiod of six years, the effect of adding fat, protein matter, carbo-hydrates, kc., t o foods deficient in these several constituents. Byadding fat they found the yield of milk and the amount of fatin i t to be both increased, but by adding protein matter only theyield was affected favourably, but not the fat. The yield of milkwas, however, increased more by adding a pmtein than by theaddition of fat. The addition of carbohydrates also had no effecton the production of milk-fat. The authors conclude that fat alonehas a specific action on the production of milk-fat. Further experi-ments with emulsified fats showed these to possess no advantage.Von Soxhlet3 has observed the coagulation taking place in thecase of milk that is faintly acid. A t first a coagulum is formedon boiling, and this takes place when only one-eighth of the acidnecessary to produce coagulation a t the ordinary temperature ispresent. The coagulation is due to the formation of an insolublecompound of caseinogen and calcium salts.F. Bordas,* by exposing milk to an atmosphere containing for-maldehyde, has found that air containing as little formaldehyde as 1part in 100,000 will give the reaction for formaldehyde, althoughthe milk may have been exposed for only a few minutes.J. AUGUSTUS VOELCKER.AW~YSL, 1906, 31, 176. ’ L n l t c l ~ . Yc~sz~chs-~Ytd., 1906, 64, 93, 249.Chem. Centr., 1906, i, 579. Compt. wnd., 1906, 142, 1204