42 P h y s i o 1 o g i c a 1 C h e mi s tlr y. Cutaneous Respiration in the Frog. By E. WAYMOU~H REID and FREDERICK J. HAMBLY ( J . Yhysiol., 1&5, 18, 411--424).--The vital o r secptory activity of the epithelium lining the a i r passages lias been recently called on to account for some of the l~henomena of rekpirstion. The present research deals with this qucJstion in con- nection with the skin of the frog, which in that auimal forms an important coadjutor to the lungs. The appsratus and method used me described a t length : the principle of the method is, that t,he skin just removed from the animal is used as a diaphragm, across which the amount of gases passed is estimated. Tile amount of carbonic anhydride whicli passes through the skin, from the inner to the outer surface, is practically the same as that which passes in the reverse direction. There is thus 110 el ideiice of secretory activity.W. D. H. By GOTTLIEB (Bxp. Stat. Rcct,/rd, 1895, 7, 148-149 ; from Verhuncll. L\rotu~-. X e d . T7er.? Heidetberya, 5).-Observxtions of th:: constant and regnlar secre- tion of the paricreatic: juice, by means of a canula, in the paiicreatic duct of a rabbit, slirJwed t h a t the introductiou of mu-tad or pepper into the swcIiacii causcd the secretion to be ttiree or iour umes as laige ; the juice was somewhat abnormally watery, h u t possessed t h e s a s e digestive properties. X. H. J. M. Wandering Cells of the Alimentary Canal. By W. B. HARIJY and F. F. WESBROCIK ( J . Yhysiol., 1895, 18, 49&-524).-The main bulk of the paper is liistological, beiug a continuation of' former work.The cells fall into the three main classes of oxyphile, babophile, and hyaline celis. A notewoithy fact made out is the existence of a layer of basophile cells a t the base of the epithelial cells covering the villi. A large nuniber of animals were investigated ; in rats fed on ;I flesh diet, the cells altered to the csxnivorou, type, the basopbile cells becoming more numerous, and scattered and mjgr ated in l a y num- bers between the epitheliuu cells ; the granules of the oxyphile cells Action of Mustard and Pepper on Digestion.were scarcely preserved by absolute alcohol, a i d did not stain readily. The absorption of iron appears to be carried out br the hpaline cells. TTT. D. H. The Lactase of the Small Intestine. 1:s FRANZ R~~HMANN and J.LAPPE (Bey., 1895, 28, 2506-2507; compare Pautz and Vogel, Abstr., 1895, ii, 403).-The authors have investigated the action of the small intest.ines of‘ calves, oxen, and yourig and old dogs, on solutions of uiilk sugar. Fhe intestines were also extracted with chlorofcxm, with tiiymol solution, and with sodium fluoride solution, and the action of these extrilcta on the milk sugar studied. I n all cases, with the exception of OX intestine, after digestion for several hours, dextrose could be identified i n the solution by means of its osazone. Alcohol prceipitates from tbe above extracts of the intestine a sub- starice which will also liydrolyse milk sugar. Qnai!titative experiments as to thc amount of dextrose formed wele also made.J. J. S. Influence of the Vaso-motor Nervous System on Meta- bolism. By F. TANGL (P$ziger’s A ~ c h i v , 1895, 61, 563-582).- Dogs were curarised, their s p i r d cord divided i n the neck, artificial respiration being kept up. The peripheral end of the spinal cord was stitnulsted, and observations made on the rectal temperature, and g:iseous interchanges before and during stimulation. The geiiersl conclusion drawn is that electrical stimulation of the whole vaso- motor system of nerves produces a fill1 of the temperatnre of the internal parts of the body, arid that tliis is due not only to increased loss of’ heat, but also to diminished developmerit of heat. W. D. H. Metabolism. By IMMAXUEL M u m (PJliiger’s B r c h i ~ , 1695, 61, 607--619).-l’his is a suppiernentary paper to one previously pub- lished (Abstr., 1895, ii, 78), and is chiefly conccmed with answering various criticisms, and explaining some parts more fully.The prs- vious general cunclusions of the author are maintained. W. L). H. Iron in Food. By I~ALPH STOCKMAN ( J . Y h p X . , 1895, 18, 484--489).-Almost t h e o d y data, with regard to the amount of iwil i u food, are those of Boussinganlt (Cow@. ?*end., 74, 1352), wd liis results are too high. Tlte great difficulty iu wclrk of this kind is corn- pl:,te incineration ; whicli, in the present research, was acconiplishcd by heating the ash with a mixture of hydrochloric and sulphuric acids ; the residue was then taken up with dilute sulphuric acid, re- duced with zinc, and titrated with potassium permanganate.The ordinary daily diet was found to coutain about 9 or 10 mil!i- grltnis of iron ; but i n chlorotic pciple, who talcc but little food, the amouiit u a s about 3 milligrams. The following articles c;f diet were also analj-sed in the same way. Milk from 2 to 4.3 milligrams per litre. Oatmeal 3.5 milligrams per 100 grams (dried). Bread from 0.61 to 0.85 milligrams per 100 grams (dried).44 'at. Ibs. 0 *33 0 '38 0 -19 0.26 ABSTRACTS OF CHEMICAL PAPERS. Carbo- Heat liyd rstee. ralue. --~--- Ibs. cal. 5 -89 14000 6 -13 14500 4 -60 11500 4 -65 12100 Yellow ox marrow 2.5 to 4 milligrams per 100 grams (dried). Red calf marrow '7.6 to 8.7 ., 7 , Beefsteak 3.9 mi1ligrn1.m per 100 grsnis (dried). 1 ) W. D. H. Sugar as a Food. By B. T. STOKVTS (Brit.Med. J., 1895, ii, 12tO-1282). By UGOLIKO Moss0 (ihid., 1282). By VAUGRAN HARLEY (ibid., 1282 -1284).-These three papers constituted the opening of' :I, discussion at the an+nual meeting of the Brit. bled. Assoc. (1895). Harley and Moss0 support the doctrine that sugar is the great source of muscular energy ; this, however, is strongly contested by Stokvis, who severely criticises the elgographic method. Mannan as Human Food. By C. TSCJI (Bul. COX A g k Imp. Uiziv., !f'ok!g?lo, 1894, 2,10.3-105).-l+om the tuberous roots of Conc- phaZlus konyaku, a food, consisting of colourless, gelatinous tablets, is p r e p a i d , and is largely consumed in Japm. It is made by mixing the grouiid root with slaked lime (1 part) and water (2 parts), after which it, is boiled with lime water until i t forms a gelatinous mass.When boiled with 3 per cent. snlphuric mid, the root yielded 55.86 per cent. of mannose, assumiiig the whole of the sugar present t o be mannose, as is very probable. The ~nannan present in the root must be digested by the enzymes in the intestines, and transformed into mannose or a dimannose, corresponding with the maltose made from htarch. Attempts to convert t!ie mannan of k o n y n h into a sugar by means of diastase from malt were unsuccessful. W. D. H. N. H. J. M. Feeding Experiments on Sheep. By CHARLES D. WOODS and C. S. PHELPS (Ann. .Rep. Storrs Ayric. J f ~ p . Stot., CO?~~Z., 1893, No. 6, 28-42, and 1894, No. i , 92--106).-h the first series of experi- ments, five sheep were fed for 12 weeks on a wide ration (maize meal, hay, and turnips), another lot of fye being fed with a narrow ration (linseed, pea and maize meal, bran? and hay), after which they were alangh tered, weighed, the various portions separated, and analjsed.Similar sheep mere slaughtcreii niitl analysed at the commencement of the experiments. The second set of experiments was similar, but the sheep were kept in a yard in groups instead of in pens. The following tables sunmarise (1) the daily amount of digestible food aclually eaten to produce a gain of 1 lb. live weight; (2) the perceutage composition of the fresh edible meat produced under the different conditions in both years. --- Wide ration, 1893.. . . Narrow miion, 1893.. ), 1894..,. >) 1894.. --I-- Ibs. Ibs. 6 -99 I 0.83 7-31 1 0'81 ti '02 1 '23 6 - 2 0 1 1.30PHYSIOLOQI CAL CEEMISTRT. 45 At commencement 1893 Wide ration, 1893 .. . . ,, 1804 .. .. Narrow ration, 1893 . . 3 Y9 1894 9 , 1894 .. In fresh meat. I In dry meat. Prote'in. 41 -4 36'6 34 -9 32.6 36**5 35-8 Ash. 2 . 5 2'0 1.9 1'8 2'0 2 ' 0 Fat. Water. -- 58 -4 55.2 57.3 52.0 58'8 54.1 5G *1 61 *4 63 -2 65 *G 61 -5 62.2 Digest,ible Amide Crude protei'n. nitrogen. fat. 0 -70 0-017 3-29 1 *ol! - 2.66 0 *6S 0,069 1.20 1-30 0 039 0.94 -- -- __I Crude fibre. 21-24 27-15 39.77 46.02 --- Protei'n. -- 17.3 16 -3 14 -9 15 *G 15 -0 16 -1 Ash. The resnlts show that the character and composition of meat depends largely on the food. The 1893 results illusbrnte strikiiigly the fact that water and fat can replace each other to a greiit extent ; whilst the protein is about the same in both series (wide and narrow rations), the meat of the narrow ration animals contains 1.5 pcr cent.more water and 1.6 per cent. less fat than the flesh of the wide ratioii sheep. Otherwise tlie results are not very decisive. N. H. J. M. Feeding Experiments with Brushwood. Bg E. RAmf (h'ied. Centr., 3895,24,445-448 ; from Landw. Juhrb, 1894, 23, 789-834). --In consequence of the scarcity of food in 1893, cxperirnents were made at Poppelsdorf in which cows, hoi-ses, sliecp, and goats were partially fed with brushwood. Corns proved to be most, suitable for the cxperinients, as tliey consumed the material i n suficisnt quantity, and did not, with one exception, suffer from indigestion. They received a constant ration of sugar beet, dried brewers' grains, earth- nut cake and salt,, together with wheat chaff (5 kilos.), which was successively replaced by birch (9-12), copper beech (6-11), and hornheam brushwood (4-5 kilos.) per day.The brushwood was freshly ground each day, and was given in different degrees of fineness. The effect of brushwood was to decrease the yield of milk, raise the percentage of fat, and, in some cases, to shorten the period of lactation. It was of great importance to have the wood very finely ground. Only the buds and bark seem to hare a value as food, a large portion of the \rood being found undigested in the faxes. Of the different woods, birch gave the best, hornbesm the worst, results. Thc following numbers shorn the percentage composition of fine beech brusliwood meal ( l j , medium and coarse beech (2), copper beech (3), hornbeam (4). - 1 2 3 4 - Dry matter .5s '47 62 -81 $2 *23 S l . 6 7 -- Crude prote'in. 3 -65 3 -35 3 .07 3 -43 IS-free extract. 24 *84 28 '54 2G '77 30 -06 I Pure ash. 0 -99 0 -96 1 *O$ 1 *14 ---4 ci ABSTRACTS OF CHEMICAL PAPERS. The percenttcge amount of lime was (2) 0.389, (3) 0.438, (4) 0,377 ; of magnesia. (2) 0.107, ( 3 ) 0 103, (4) 0 15s; of phosplioric acid, (2) 0 143, (3) 0.146, nrd (4) 0.125. The results show that' in years of scarcity of the ordinary foods, brushwood dmerves attention. Some animals, however, cannot be fed with it at all, and i t is unsafe to employ i t For lon? periods as an csclusire substitute for forage. Examination of Foods from Farms where Cattle suffered from Brittleness of the Bones.By OSCAR KFLIJER, A. KOHLER, and F. BARKSTEIN (Bi~d. Cmtr., 1895, 24, 441-443 ; from ~ S a c / ~ s . landw. Zeit., 1894, No. 15).-AnElyses werc m:de of five samples of hay and three of straw, produced in the dry sewon of 1803. The aniount of phosphoric acid was, in every case, very low. There is no direct evidence to show that bone brittleness can ay'se from want of phosphates, but Fiirstc-r, Stillnig, and von &ring proved that it may be caused by insuficient supply of lime. Inasmuch as lime and phosphoric acid always occiir in the same relative amounts in the bones OF young animals, a deficiency of phosphates in the food may cause Rn insufficientJ deposit of lime in the bones, and with older animals, deficiency may cause a withdrawal of both phosphoric acid and lime from the bones, which would thus become brittle.The disease can generally be cured by good feeding and a dailyallowance of bone meal (30 to 60 grams) ; 011 farms where bone softening prevails, the crops should be well manured, especially with soluble phosphates. Fittbogen showed that plants, when insufficiently watered, am unable to take up phosphoric acid in suEcient amounts. Action of Drugs on the Embryonic Heart. By JOHN W. PICKERING ( J . Physiol., 1895, 18, 470483).--This is a series of further experiments in answer t o ccrtain criticisms by His (Cent?-. Phpid., 1894, 8, 11). The chief points made out are the following : -'l'he combined accelerator and augmentor action of small doses of alcohol on the heart of the embrjo cliick, reaches its maxirnuni at about 38" ; a t low temperatures, even smd1 doses of alcohol rapidly depress the cardiac rhrthm.A temperature of 40" and upwards has a marked influence on the action of alcohol on the embryonic hf.art ; the frequency becomes too rapid to record, and the force of the beats is much diminished. A dose of alcohol, which, a t 20°, is a depressant, has an accelerator action at higher temperatures. The maximum accelerator action of alcohol is attained more rapidly at a lower than at a higher temperature ; the depressant, action is affected siinilarly. The cardiac stoppage produced by moderate closes of alcohol at a l o w temperature can be usually removed by heating, or by the application OF electrical stimuli ; similarly, the cardiac stoppage produced by small doses of alcohol at a high temperatare, can sometimes be removed by cooling ; electricd stimulation, Iiowever, induces a condi- tion not unlike tetanus.A dose of 0.1 milligram of veratrine (dis- solvecl in 0.65 per cent. sodium chloride solution) acts as a dcprcssatit to the embryonic heart a t 20°, but, at a temperature above 30", pro- duces a marked acceleration of cardiac frequency ; n dose of 0.3 rnilli- N. H. J. M. X. H. J. M.PHPSIO L,OQICAL CHEMISI’RT. 47 1. O.OitC(i 5. 0,0363 2. 0 -0388 6. 0 *0384 3. 0.0236 7. 0.0368 4. 0.0334 - Percentnge of Fe,O:, in blood in successive weeks gram of vcratrinc is fatal a t 20°, whilst a t 42’, the avcragc! reduction of cardiac frequency is t ~ o beats per miniite. Ammonia, acting nt; 38O, lias R mnrked accelemkiyg ackion. Former experiments haT-e shown that in eady embryos, br.fo1.e tlio beart n e n w are developed, mascarine has no action ; it, however, depresses the cardiac rhythm of chick embryos older tha!i 200 honrs, its action culminating in diastolic stoppage, which can be removed by the subsequent, application of atropine sulphnte.:IS in frogs. The restomtion is onlj- putially complctc., i f msscatrine stoppage has been induced. The action of mascarine nitrate is more marked a t snl)- normal temperatures, :uid caii often be removed by the application of heat. W. D. H. 7- 1. 0.0445 a. 0 0234 3. 0,0503 G . 0 *0227 3. 0.0259 7. 0.0195 4. 0.0303 - Formation of Blooii from Inorganic Iron. By 30s. A. Kun.Kcr, (P’iigw’s 11 i*chip, 189.5, 61, 595--606).-As a contribution to the disputed qnestiorr whether inorpnic iron is absorbed and contribn tes to blood (hmrnoglobin) formation, experiments were made on two puppics ; one rect>i\-ed milk, in which the amount of iron was as~~eiq- tailled, the other the same food p l u s iron.The milk coiitained ahout I niilligrr~~n of metallic iron (1.4 milligram Fe,O3> per litre. The cxtra iron given daily was 30 drops of liquor ferri albuminat of f h e German Pharmacopceia (= 4.4 milligrams of iron). During life, tho blood was examined at, weekly intervals. After drath, other organs were submitted to an:dysis. The main facts we given in the follow- ing table. I t shows a greater amount of iron in tlie dog to which iron had been administeyed. Weight. -~~~ ~ ~ I Dog A, with iron.I Dog B, without iron. Total Fe.,O,. grams 151 -3 7 *3 30 *2 9 -9 - After death. gram 0.0252 0 0043 0 0013 0 *0014! 0 -0301 1. Total blood.. ....... 2. Liver ............. 3. Splven ............. 4, Kidneys.. .......... 5 . Ribr ............... Weight. p i n s 133 *8 7 - 2 27 -0 11 -1 -- I Total Fe,O,. gram 0 *o 404 0 ‘0317 0 ‘0043 0.0025 0’0011 Physiology of Blood Sugar. By F. TAFGL and VAUGHAS HARLEY (Zyiiger’s ~l.rc/ziv, 1895,61,551--559).-Most phrsiologists look on thc liver as the source of the sugar in tho blood ; support is lent to this doctrine by the f w t that i f the liver is excised or excluded from the circnlatii>n, sugar disappears from the blood. Interference with tlie cirenlation of the liver by ligature of the intestinal arteries lessens its activity (compare Slosse, DIL Rois Reymords Arch., 1890, 482, on4s ABSTRACTS OF CHEMICAL PAPERS.the diminution in nrea so produced), and the present experiments in dogs sliow that this is true for its sugar forming functioii; the quantity of sugar in the blood markedly diminishing (from 42 to 92 per cent. in different experiments) after the ligature of the arteries in question. W. D. €I. Circulation Time. By GEORGE N. S m w A n T (Brit. Med. J., 1895, ii, 1287).-Thc method employed consists i n the injection o€ msthy- lene blue into a vein and watching for its appearanco in the carotid artery. This simple method gives identical results with the elec*trical method of the author. The mem pulmonary time in a clog is 9-55 seconds; and i n different animals this varies as the diameter of a sphere of the same mass as the animal, and having the same specific gravity.The circulat,iori time in a man is probably about 15 seconds, which is considerably shorter than that stated by the oldel. experimenters. W. D. H. Muscular Work and Glycogen. Ry FR. SCHENCK (Pjliiger’s Aychiv, 1895, 61, 535-543) .-Seegen ( U I L Hois Il‘eymowd’s Archie., 1595,242), from experiments on dogs in which he stimulated the nerve of the qnadriceps muscle, concludes that, the glycogen m~liicli dis- appears will account for only five per cent. of He looks on the sugar of tile blood as the normal source of rniisculatl* energy, and glycogen as a reserve called into use only when work is excessive. The present article tr,i.verses these statements, and speaks in favour of PBiiger’s theory.Tlie chief objections raised are that tho work done in Seegen’s experiments was not maximal, and that no proof is given that the glycogen which disappears is burnt up ; i t mipht, a,s indeed Seegen appears to admit, be converted into sugar, how then is the mgar of the blood to be distinguished from that originating from glycogen ? W. n. H. Proteids of Muscle Plasma. By OTTO VON F~~RTII ( A I - c ~ . exp. Path. Yha~rn., 1895,36,231--274).-Muscle plasma was obtained from muscles free from blood by extracting them with physiological salt solu- tion. This coagulated spontnneously, and the clotted proteid formed is called myopen-fibrin, 01’ myosin-fibrin. The protejids in the muscle piasma are three in number, namely paramyosinogen 17 to 22 per cent,.of the total proteiid, myosinogen or myogen 77 to 83 percent. of the total prote’id, and traces of serum albumin probably derived from the re- mains of blood and lginph left in the muscles. The whole paper is written rery largely in reference to previous work by Kiihnc and Halliburton (Abstr., 1557, 954). The work of IIalliburton is confirmed in its main point, namely that there are two pi-ote’ids in tho muscle plasma, paramyosinogen and myosinogen which enier into the formation of the muscle clot ; t h e action of a specific ferment to bring about this change was not specially investigated. The principal new fact made oiit is that para- niyosinogen passes into this condition of myosin-fibrin directly ; whilst it) the pssage of myosinozen into the state of inyopi-fibrin, It is not necessary to open the artery. the work done.PHTSIOLOOICAL CHEMISTRY.49 there is an intermediate soluble stage coagulated by heat a t the Imemarkably low ternperatnre of 40°. Parit?nyosi?zogen is a typical globulin, and is regarded as identical wit11 Kuhne’s myosin. Myosii~ogen is described as differing from a globulin in man,)- particulars ; it is spoken OF as a prote’id s u i gene&. The prote’id in the muscle serum, described as myoglobulin by Halliburton, is not regarded as a, definite substance, but only as a part of the myosinogen which has escaped coagulation. The pheno- menon described by Halliburton as recoagulation of myosin, is regarded only as a reprecipitation of globulin. Peptones, albumoses, nucleo-prote‘ids were not found (compare Whitfield.Abstr., 1894, ii, 358). The muscle plasma from fishes’ muscle contains amther prote’id called rnyoproteid. It gives the usual prote’id reactions, and is readily digested by gastric juice ; it is neither coagulated by heat, nor precipit- able by removing the salts by dialysis. It is precipitated by neutral salts like globulins. It is precipitable by acetic acid, but is neither a mucin nor a nucleo-proteid. The same substarice was found in crab’s muscle, Antagonism between Salts of Calcium and those of Sodium, Potassium, and Ammonium. By SYDNEY RINGER (J. f h y s i o l . , 1895,18, 425--429).--Milk to which rennet and calcium chloride have been added clots readily, whilst the presence of sodium chloride hinders, or in larger amounts prevents, this action; the chlorides of potassium and ammonium act similarly, but less power- fully than that of sodium.This antagonism is limited to the preci- pitation of the casein as a clot, and does not affect the chemical change from casejinogen to casejin produced by the rennet ferment. The same antagonism exists in relation to blood clotting, and to muscular contrachior! as evidenced by experiments on the frog’s heart, only in the last case potassium chloride is a more powerful antagonist thau sodium chloride. W. 1). H. Toxic Substance from the Supra-renal Capsules. By D. GOURFEIN (Compt- reqzd., 189& 121, 311--314).-The glycerol extract of the supra-renal capsules contains protejids which are precipitated by alcohol, and have little or no toxic effect, together with substances which arc not precipitated by alcohol and are highly toxic.As the latter are not decomposed by heat, the capsules can be extracted with hot water, the solution precipitated by alcohol, and the clear liquid evaporated on a water bath. The product when injected sub- cutaneously causes death in 8 short time, and seems to act on thc central nervous system. The proportion of the poison in the supra- renal capsules is variable, but no similar effects are produced by extracts of the spleen or the muscle of the same animals treated in the same way. By FRITZ PREGL (P’iiger’s Archi,,, 1895, 61, 359-406) .-The intestinal juice has been investigated chiefly in carnivora. The only previous experiments on herbivora were made on a goat by Lehrnann, who found the juice had no digestive action.The present experiments were made on a lamb. W. I_). H. C. H. B. SUC~US Entericus of Sheep. VOL. LXX. ii. 550 ABSTRACTS OF CHEMICAL PAPERS. The juice was collezted by a modificat'ion of the Thiry-Vella method, from 3 to 5 grams of juice being obtained from the loop per hour. I t is a mucous, strongly alkdine fluid, which is rich in prote'id, and tends, like pancreatic juice, to set into a jelly spontaneously ; its specific gravity is about 1.014. It contains about 0.2 per cent. of urea. The following analysis is given in parts per 1000. Sodium carbonate ............. 3.69 Albumin and globulin.. ........ 18-09 Albumoses and mucin .......... 1.27 Urea ......................... 2.29 Other organic substances .......3.31 Ash... ....................... 1.27 Water.. ...................... 970.05 On proteids, cellulose, pentoscs, and fats, i t has no digestive action, but it converts starch and glycogen into dextrose with intermediate dextrins ; it inverts cane sugar and maltose, but not lactose. Artificial Hydrzemic Plethora. By J. B. LEATHES (&it. Med. J., 1195, ii, 1287).-The experiments briefly recorded go against the secretion theory of lymph formation. By HAKTOG J. HAhrBuRGER (Brit. Med. J., 1895, ii, 1287).-The disappearance of fluids from the serous cavities can take place either by the lymphatic or blood vessels; ihe process is not one of osmosis, for both isotonic and hypertonic solutions disappear, and Heidenhaim concluded that a vital activity of the epithelium must occur to account for the pheno- mena.The force a t work is believed to be imbibition of the molecular kind, such as occurs with gelatin and other homogeneous substances, and this imbibition may be exhibited by the cells or by the cement substance between them; this is of course limited in tt dead animal, but in n living one the circulating fluid removes the absorbed liquid. A working model to lrluslrate this has been constructed as follows: a cylinder of gelatin is taken to represent a capillary, and enclosed within a wider glass cylinder to represent the tissue spaces ; both cylinders are now filled with a fluid like serum, and if a stream is kept up through the gelatin cylinder, the fluid is absorbed from the space between the two cylinders, and is replaced by fresh fluid allowed to flow in through a side tube.The hydrostatic pressure of the fluid is also to be taken into amount. W. D. H. W. D. H. Physical Factors in Absorption. Absorption occurs, however, in a dead animal. W. D. H. Potassium Thiocyanate in Saliva. By IMMANUEL MUNK (P'iiger's Archiv, 1895, 61, 620-622) .-In reference to Nencki's work on thiocyanic acid in the stomach, itl is pointed out that in the dog, it is absent in the saliva ; horse's saliva is also free from it. W. D. H. Elimination -of Calcium Compounds in Rachitis. By WIL- LIAM OECHSNER DE CONINCK (Conjpt. rend., 1895, 121, 262-263).-PHYSIOLOGICAL CHEMISTRY. 51 I n cases of rachitis, the quantity of calcium in the nrine gradually diminishes in the same manner as the quantity of niagnesiuni.When e1imir;ation of magnesium is small, however, that of calcium is rela- t,ively high, and this result has led the author t o conclude that in yachitis the calcium of the osseous system is partially replaced by magnesium. Chabri6 has arrived at A similar conclLzsiou with L- respect to osteomalagia (compare Abstr., 1895, ii, 455). C. H. B. Urobilin. By ADOLF JOLLE~ (PJEiiger’s Archia, 1895, 61, 623- 637).-Urobilin was first described by Jaff6 in febrile urine, later, Maly obtained from bilirubin, by reduction, a substance he called hydrobilirubin, which he considered to be identical with urobilin, and Vierordt pointed out that normal urine contains other pigments as well. MacMunn distinguishes between normal urobilin and febrile or pathological urobilin, which differ in their optical characters ; fresh urine containing little or no urobilin often becomes darker on ex- posure to the air, and this he considers to be due to the oxidation of a chromogen, urobilinogen.Both MacMunn and Hoppe-Seyler have obtained ui-obilin by artificial means from haematin. MacMunn and Le Nobel both doubt the absolute identity of urobilin and hydrobili- rubin. Pathological urines, dark from the presence of supposed bile-pigment, have shown in many cases, on examinatim, that the increase of urobilin is the cause of the deep colour of tbe urine (urobilin-icterus) ; whilst recently A. Katz (Wiener Hed. ?Voclz., 1891, Nos. 26-32) has shown that this increased excretion OE urobilin is due to metabolic changes having their seat in the liver, which if they me prolonged produce hamiful changes in the liver cells.The present paper points out that urines containing a small amount of bile-pigment will, after standing exposed to the air for several days, no longer show any bilirubin whatever, nrobilin having taken its place. The source of the urobilin in the faces is also doubtless the bile-pig- ment, unaltered biie-pigment never occurring in normal faxes. Urinary nrobilin shows two well-marked characters : (1) a green fluorescence, -which appears when tlle urine is rendered alkaline with ammonia and a few drops of zinc chloride solution are added ; (2) a well-defined ab- sorption band between the lines 7, and F ; i t was necessary to determine if auy other urinary pigments give the same characters.Gmelin’s test for bile-pigment consists in adding fuming nitric acid; the colonr changes t o blue, violet, red, brown, and finally jellow, the yellow end product, of oxidation being called choletelin ; these coloured products, with the exception of the last, when reduced by zinc and hydrochloric acid, all show absorption bands, and give with ammonia and zinc chloride a green fluorescence. The absorption bands given by the red and brown pigments are in the neighbourhood of the E’ line, but not so sharply defined as in the urobilin spectrum, which, however, theg closely resemble. I n some urines, pigments can be separated which give all the characters of the red and brown oxida- tion products of bilirubin, whilst others again yield a substance identical with choletelin, which is the highest oxidation product of bilirubin, and is, in fact, regarded as the yellow pigment of normal urine; for the details of the method of separating the pigment 5-252 ABSTRAOTS OF CHEMICAL PAPERS. from urine by lead acetate, &c., the original paper must be consulted. In conclusion, two classes of urobilins are distinguished from one another, pathological urobilins, which are reduction products of bili- rubin, and physiological u~obilins, which are oxidation products of bili- rubin.These terms are used in R different sense from that in which MacMunii uses the terms normal and pathological urobilin ; but the idea that normal or physiological urobilin is an oxidation product of blood or bile-pigment should be credited to MaoMunn. Among the physiological urobilins is reckoned the substance which darkens on exposure to the oxygen of the air.The source of physiological urobilin is considered t.o be the bile- pigment; pathological urobilin lias usually the same origin, but it can come from blood pigment directly after extravasations of blood. W. D. H. Action of Anaesthetics on Nerve. By Au~us~ns D. WALLER (Proc. Physiol. Soc., 1895, 45--47).-A frog's sciatic nerve is laid on two pairs of electrodes, one pair being exciting, the other pair non- polarisable, and leading to a galvanometer ; ou excitation, the elec- trical change in the piece of nerve connected with the electrodes is noticed. The whole is contained in a chamber, through which gases or vapours in known amount can be passed.In large amount, carbonic anhydride produces primarily abolition, secondarily augmen- tation of the effect observed, whilst in small amount (for instance, with expired air) there is primarily augmentation. Ether produces prolonged abolition, followed in time by recovery, whilst chloroform produces abolition, but no recovery occurs ; other anaesthetics were also investigated. The most important point made out is regarded as evidence OE the production of carbonic anhydride in the nerve itself, conse- quent on activity, for after prolonged excitation the effects of inter- mittent stimulation is to produce an increase of the galvanometric change, just as though a small percentage of the gas had been added to the surrounding air. W. D. H. Action of Carbonic Oxide on Man.By JOHN S. HALDANE (J. Physiol., 1895, 18, 430-462) .-The expei*iments made by the aGthor on himself show that the symptoms caused by carbonic oxide depend on the extent to which the haemoglobin has been saturated ; the percentage saturation of the haemoglobin of the red corpuscles may be estimated during life by a simple colorimetric method. Carbonic oxide is a " cumulative " poison. The symptoms do not become sensible during rest until the corpuscles are about one-third saturnt'ed ; with half saturation, t,he symptoms (respiratory distress, headache, &c.) become urgent. Similar symptoms are experienced by mountaineers a t high altitudes. When air contaiiiing this gas i5 breathed, about half of that actually inhaled is absorbed, except when absorption is coming to a standstill. The time required for the production of sensible symptoms in an adult depends on the t'ime required for the inhalation of about 660 c.c., or fhe absorption of about 330 C.C. of the pure gas; this time ill different animals varies with the respiratory exchsnge perVEGETABLE PHYSIOLOGY AND AGRICULTURE. 53 unit of body weight, and is about 20 times as long in a, man as in a, mouse ; hence a mouse can be used as an indicator in a coal mine before men penetrate into it. The maximum amount of carbonic oxide capable of being absorbed by the blood from air containing a given small percentsge depends on the relative sanities of oxygen and carbonic oxide for hEmo- globin, and the relative tension of the two gases in arterial blood. The affinity of carbonic oxide for haemoglobin is about 140 times that of oxygen, and the oxygen tension of human arterial blood is, approximately, 16 per cent. of an atmosphere. Distinct symptoms, appreciable during rest, are not produced until about 0.05 per cent,. of the gas is present ; with about 0.2 per cent. urgent symptoms are produced. With a given percentage of carbonic oxide in air, a certain percentage saturation of the blood is reached within about 150 minutes, and is not afterwards exceeded, however long the breathing of the vitiated air is continued. The disappearance of the gas from the blood when fresh air is again breathed is always much slower than the absorption of the gas, and is chiefly due to dissociation of' carbonglhaemoglobin by the mass influence of the oxygen in the pulmonary capillaries, and consequent diffusion of the gas outwards through the alveolar epithelium. W. D. H.