PHYSIOLOGICAL CHEMISTRY.DURING the year 1912 no prominent person in the bio-chemicalworld has passed away, nor are there any new books in thisbranch of science to announce. The only item of general newsnecessary to mention is the fulfilment of the hope expressed in lastyear’s report that the Bio-chemical Club founded in 1911 wouldblossom into a Society with a journal of its own. This is now anaccomplished fact. The Rio-chemical Journa2, which has hithertobeen edited by Professor Benjamin Moore and Mr. Whitley, ofLiverpool, will in future be conducted by the newly-founded Bio-chemical Society, and issued by the Cambridge University Press.As editors, the services of Professor W. M. Bayliss and Dr. A.Harden have been secured ; bio-chemists will watch with interest thenew enterprise, and wish it every success.Periodical literature, which it is the special duty of this reportto review, was never more bulky ; physiological chemistry is stillremarkable among the sciences for i@ fruitful and steady growth.The papers published deal with every corner of the science, andadd fresh bits of knowledge to many subjects.The mere fact,however, that in the general run the expression “bits of know-ledge ” is correct, renders the arrangement of a systematic resumedifficult within a reasonable space.Among the many problems a t which work has been diligentlydirected the following few are the most important. The gaseousmetabolism in individual organs is still steadily being examinedunder the leadership of J.Barcroft, but there are no striking newfacts. What has appeared relates to organs other than those previ-ously examined, the same methods with slight modifications hereand there having been employed. This sort of work is none theless valuable, but the accumulation of data is always dull workfrom the reviewer’s point of view. Closely allied to this questionis the continued discussion as to whether there are any circum-stances under which the lining membrane of the lung activelysecretes oxygen into the blood. J. S. Haldane and his co-workershave definitely abandoned the view that such secretion takes22222 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY,place normdly, and investigators are now happily unanimous thatphysical diffusion alone explains the gaseous interchanges whichoccur in the lung.The upholders of the secretion theory, how-ever, still feel doubt whether that theory should be abandonedaltogether, and believe that under stress (for instance, at greataltitudes) the pulmonary epithelium is able to exercise the propertyof piling up oxygen into the blood which it inherits from theswim-bladder of ths fish. Renewed work can alone show whetherthey are right.The ductless glands are still fertile fields for work, and perhapsthe most interesting papers which have appeared on this subjectare those by Prof. Carlson and his colleagues a t Chicago on therelationship of the thyroid and parathyroid bodies to tetany. Theaction ol adrenaline again is not fully worked out yet, and quitea large number of papers have appeared on this subject.It isoften noticed that the effect of a drug on an isolated organ differsfrom that which ensues when the same organ is in the intact body:for a drug may act indirectly on an organ by stimulating thesuprarenal gland to activity, and the effect observed is really anadrenaline effect.Dale and Laidlaw 1 have worked out this ques-tion especially on the uterus and on the eye, and it appearsfikely that this factor will play an important part in future investi-gations; and no doubt other organs than the suprarenal will havealso to be reckoned with.Since the foregoing paragraph was written, a series of papers2from Starling’s laboratory has appeared, which demonstrate theimportance of the suprarenal factor in many cases of elevatedblood-pressure where it was previously unsuspected.The rise ofarterial pressure which occurs, for instance, when the splanchnicand other nerves are irritated, or when the amount of carbondioxide in the blood is increased, is in part due to the pouringout of adrenaline into the circulation.The activities of enzymes of all sorts, the lipoids, creatine andcreatinine, the scientific exploration of drug actions, the largesubject of immunity and its offshoots, such as anaphylaxis, all theseand many others claim mention in the year’s output.The wide word metabolism covers a multitude of researches, andneaqly every aspect of this important subject has received atten-tion. One may particularly single out, for a passing reference, thequestion of nuclein metabolism, and express the hope that Levene1 Proc. physiol.Soc., 1912, xii, J. Physiol, 44 A., ii, 667. Also J. Physiut,1912, 45, 1 ; -4,, ii, 854.G. von Anrep, J. Physiol, 1912, 307, 318 ; S. Itatni, abid., 338 ; A., 1913, i, 121,136.One only I will mention a little more fully in passingPHYSIOLOGICAL CHEMISTRY. 223and his fellow-workers will succeed in unravelling the constitutionof the animal nucleic acids. I dealt with the question of nucleicacid a t some length last year, and it is too soon to make freshpronouncements ; the nucleic acid which Levene made the subjectof his .noteworthy work was mainly of vegetable origin (for instance,that of yeast), and this he showed to be a complex of phosphoricacid, certain bases, and a pentose (ribose).In the acid of animalorigin (for instance, that from the thymus gland), the place of thepentose is taken by a hexose, and one awaits with considerableinterest the work already started in relation to it.sAfter this rapid review of some of the aspects of the year’s work,l e t us now pass on t o enumerate the subjects which I have chosenfor a more extended notice.I shall take up first one or two subjects suggested by the well-worn but still unsettled theme, “The origin of life.” Next Ipropose to deal with certain aspects of metabolism, namely, repair,growth, and synthesis in the animal body. Then will follow some-what more briefly a review of a few important recent papers onblood-clotting, and finally I shall conclude with equally shortreferences to two pathological subjects, namely, dropsy andneuritis.The Origin of Life.This subject loomed large on the horizon during the autumn,for it was naturally the part of Professor Schafer’s PresidentialAddress at the Dundee meeting of the British Association whichattracted popular attention.The extremely useful and lucidaccount of recent physiological progress which he gave as a sequelto the more speculative portion that opened the address passedalmost unnoticed. We should all, of course, like to know forcertain what was or what is the actual origin of life on this planet,but that, also of course, was just what Professor Schiifer failed togive us. The speculations advanced were given with due scientificcaution, and as the years go by and knowledge grows, hypothesesrest on surer foundations, bu€ the time has not yet arrived whenone can assert with safety that a living organism or a livingmolecule is only the result of chemical and physical forces operat-ing on inorganic parent material.One may perhaps be boldenough to state that it is becoming more and more difficult to denysuch an assertion,It is not, however, my object to continue in these pages thelengthy and sometimes futile discussions which sprang out of theaddress, in the newspapers, a t the sectional meetings of the Asso-ciation itself, and more recently in Science Progress. It howeverLevenenlid Jacobs, J. Biol. Uhem., 1912, 12, 377, 411 ; A., i, 926224 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.occurred to me that it might be of interest to deal with one or tworather more matter of fact pieces of original research which aresuggested by the phrase “ The origin of life,” although the relation-ship may not be obvious a t first sight.The first of these may be entitled the Continwtnce of Life.Fromthe very earliest days of scientific physiological experiment theimportance of a study of the excised portions of a dead frog’s bodywitg recognised, and our fundamental notions of such phenomenaas the contraction of muscles and the beating of the heart arederived from such investigations. The far-reaching results whichhave followed the investigation of what it is now the custom toterm (‘ surviving organs ” are known to every physiologist, and areapprehended even by the first year’s student of that science.Nowthat it is possible to apply this method to mammalian organs also,the additions to knowledge have been still greater and of morepractical benefit. Thanks to the fluid known as Ringer’s solutionas modified by Locke, one is now able to keep an isolated mam-malian heart under observation, and manifesting all its livingactivities for hours, and even for days. Thanks to Ross Harrison’smicroscopic technique, it is possible to keep snippets of embryossmall enough for histological observation, aliv’e and active in ahanging drop of lymph; one can see the cilia still moving, one canwitness the transformation of an undifferentiated protoplasmic massinto a striated muscle fibre, and, above all, one can watch the nervefibres growing out of nerve cells, and shooting forth in a distaldirection a t no mean speed.Harrison was thus able to show bydirect ocular evidence the truth of His’s doctrine that the peri-pheral nerves are the outgrowths distalwards of processes from thecentral nerve cells, a doctrine which was accepted previously oncircumstantial evidence alone.It is true that in such observations, no living properties arebestowed on the matter under observation, but the mere fact thatliving activities can be maintained by purely artificial means of achemical nature, after the organism as a whole is dead, renders itincreasingly di5cult to postulate any specific and mysterious vitalforce.Wonderful as such results are, they are entirely thrown intothe shade by the more recent achievements of certain investigatorsa t the Rockefeller Institute of New York.By the use of appro-priate culture fluids, the cells of cmcerous and other tumours havebeen watched growing and multiplying for weeks, and A. Carrel4has succeeded in keeping his tissues alive longer than two months.I n general terms the culture media employed are the plasma andJ. Experi?iz. Med., 1912, 15, 516 ; 16, 165PHYSIOLOGICAL CHEMISTRY. 225serum of blood at a suitable temperature, but the tissues remainin it latent phase in cold Ringer’s solution, and resume activitywhen warmed. His most striking experiment was done with frag-ments of heart muscle; such fragments grew and commenced topulsate, and were still pulsating in vitro three months after theywere removed from the body.Carrel was previously known for hisexpert surgical skill in transplanting blood vessels and otherorgans, an entirely different branch of research, and the NobelPrize he has just been awarded is some slight recognition of thevalue of his investigations.The other set of experiments to which we will now pass are in asense the counterpart of these, Just as organs which underordinary conditions would be dead can be made to live, 80 methodswhich were previously employed only for dead organs can now beapplied to those which are alive. I refer to what is called Zntra-vitam staining, of which Prof. Goldmann, of Freiburg, is the chiefexponent.Prof. Goldmann has published several monographs onthis subject, and his most recent one is in the Beitrage f, Klin.Chir.6 A very useful summary of his main results appeared in theProceedings of the Royal Society about the same date.6 The oldermethods in which methylene-blue was injected into the blood streamwere limited t o the differentiation of specific tissues; Ribbert wasthe first to attempt a vita1 stain by intravenous injection ofcarmine; but the results achieved were so uncertain that suchmethods never passed into general use, and the toxic effects of theinjections were usually sufficient to kill the animal.A new departure in this field resulted from the attempts to curediseases caused by trypanosomes and other protozoan parasitesthrough the agency of aniline dyes, such as trypan-red and trypan-blue; and BouflFard, of the Pasteur Institute, investigated the histo-logical appearances in the cells of the body which ensued.Quiteindependently Goldmann took up similar work, and made anextensive study of normal rats and mice injected with trypan-,isamine-, and pyrrhol-blue solutions. His early results werepublished in 1909, and since then his method has been improved,and the work extended to include pathological conditions. Aftersuch injections the animal suffers from no ill-effects, and the onlyoutward sign of a change in a white rat is that it is now a blue rat.When the animal is subsequently killed, the sections prepared fromits tissues are found to be differentiated by the stain in a chwacter-istic way; those of us fortunate enough to see the demonstrationswhich Prof.Goldmann gave before the Royal Society and thePhysiological Society were struck, not only with the beauty of the1912, 78, 1. 1912, 3, 85, 146.REP.-VOL. IX. 226 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.preparations, but also with the usefulness of the new method in theelucidation of function. The dye can be administered either intrapvenously, intraperitoneally, or subcutaneously. The actual detailsof the technique, and the chemical constitution of the dyes men-tioned and also of others which have been recently added to thelist will be found described in full in the papers already quoted.What we me mainly concerned with here are the results.The stain is embodied in the granules of specific cells throughoutthe body. Although it circulates in the blood, no blood corpuscletakes it up, nor has it any effect on the vascular lining.I n theskin it is found in the fixed connective tissue cells, but chiefly infree cells in the lower layers of the cutis and subcutis. But thesemigratory cells appear also in every internal organ (except thenervous system), and always in connexion with interstitial fibroustissue; they occur in muscles, glands, tendons, and especially inserous membranes. They have chemotactic irritability, and arephagocytic. On account of their affinity for pyrrhol-blue they wereoriginally termed pyrrhol cells, and it seems probable that theyoriginate in the bone marrow.By means of intra-vitam stains one can further differentiate theKupffercell of the liver, the reticulum cell of lymph glands andspleen, the interstitial cell of the testis, the follicular cell in thematuring follicles of the ovary, the cortical cell of the suprarenal,the epithelial covering of the choroid plexuses, and the cells whichline the convoluted tubules of the kidney.When pregnancy occurs in the stained animal, the appearanceand behaviour of the placenta are most striking; the blue colourdisappears from the skin, and is concentrated in t.he uterua, andin time the latter, forming a centre of attraction for the dye, ulti-mately dispossesses all the remaining tissues of their blue, In theuterus it is the free cells of the decidua serotina where the stainia mainly found.In quite early stages the stained cells penetrateinto the primitive placenta and cast off their stained granules,which ar0 snatched up by foetal cells in the way nutritive materialis. When once the placenta has attained maturity, however, the dyeis found only in the foetal cells which form the layer that separatesthe maternal and foetal tissues. The embryo itself remains per-fectly colourless, the stain not being able t o penetrate this protec-tive barrier. Further research haa shown another important point ;for the same cells which vigorouely absorb the vital stain store alsoglycogen, fat, and hemoglobin temporarily before these substancespass into the foetal circulation.The avidity of such cells for thedye is thua connected with their functional activity in relation toreally nutritive material; the importance of vital staining inembryological research is therefore apparentPHYSIOLOGICAL CHEMISTRY. 227Equally important are its applications to pathological research.I n the healing of wounds the pyrrhol cell appears on the sceneafter the initial emigration of leucocytes has taken place. It eats upthe leucocytes or ingests the glycogen and fat which are derivedfrom leucocytic disintegration. Eventually it becomes the spindlecell of the new connective tissue in the scar, and simultaneouslyloses its affinity, both for the blue dye and for fat stains.I n trichinosis the activity of the pyrrhol cell is prominently dis-played ; it wanders towards the uncapsuled parasites, passing in itsway through lymphatic glands.The cells then spread into theinterstitial muscular tissue, and finally, penetrating the sarcolemma,arrange themselves on the outer surface of the imprieonedtrichinae.In tuberculosis a fundamental difference was discovered in thedistribution of avian and bovine bacilli when grafted into theperitoneal cavity of the mouse. When bovine material is employed,i t first cause-s extensive tuberculosis of the peritoneum itself, andthe chief seat of further trouble is in the lungs, whither the bacilliare carried by the blood stream after penetrating the portal vein.The pyrrhol cells take no active part in this acute form of experi-mental tuberculosis.An entirely different result follows injectionof the avian bacillus. The peritoneum and the organs within itshow hardly any trace of the disease. The omentum, however, isfull of blue patches, which are composed entirely of pyrrhol cells,the blue protoplasm of which is choked with myriads of bacilli. Theliver, spleen, mesenteric glands, and to a less extent the lungs are alsostudded with similar aggregations of pyrrhol cells which have actedas phagocytes and so protect the animal from the disease. In theliver the Kupffer cells play a similar r61e. In the end, however,the protective action ceases, and the brave defenders succumb whenthe parasites increase still further. The pyrrhol cells then lose alsotheir affinity for the blue dye, and show an increased affinity forfat stains, and finally disintegrate, allowing the bacilli to be distri-buted t o the body generally uia the lymphatic vessels, and not bythe blood stream as in the case of the bovine bacilli.I n toxic degeneration of the liver produced by poisons such asphosphorus, the organisation after such non-inflammatory necrosisis attempted by vitally stained pyrrhol cells, which migrate alongthe liver lymphatics from the peritoneum towards the diseasedtissues, and eventually assist in the repair of the damage.Last, but not least, the new method appears destined to play apart in the elucidation of the mysteries of cancer and similar malig-nant growths. Here the aggregations of blue-stained pyrrhol cellsattain extraordinaq dimensions ; they swarm round the growingtumour, penetrating i t along its numerous blood vessels.I n theQ 228 ANNUAL RESORTS ON THE PKOGRESS OF CHEMISTRYinterior most of them succumb. It is just here that the interestingstory stops, or is to be continued in Professor Goldmann’s next?He is content to state that he a t present regards the appearanceof the blue cells as a specific local reaction induced by the tumourcell. No other migratory cell is attracted, and i t may be thatthese cells are the bearers of nutriment. He has, however, alreadycommenced some experiments on mouse tumour with Ehrlich’sicterogen and sodium iodophenylarsenate. These poisons producetoxic degeneration of the liver, and are more powerful in thisdirection than phosphorus. The pyrrhol cells then absorb thedegenerated products of the liver cells, preferably t-he bile-pigments,and transport them to the malignant growth.Hence the latter maywear both on its smface and in its interior a distinct yellow orjaundiced appearance. Since the tumour evidently suffers throughthe application, it does not seem improbable that the pyrrhol cellmay also be active, or may be rendered active in transportingmaterials t o the tumour which impede and even stop its growth.It will be seen that this subject promises to become one of greatimportance from the biological point of view, and zt8 time goes onthe more specially chemical aspect of it will become clearer. Themore strictly chemical side of the question, both in reference to thedyes themselves and to the method of their action on livingcells, is treated in two interesting papers by W.Schulemann.7Repair, Growth, and Synthesis in the Animal Body.Our increased knowledge of the composition of proteins, the(‘ flesh-forming ” constituents of diet as Liebig termed them, hasshown us that all of the members of that large group have veryunequal powers in repairing the body waste. It is also now recog-nised that repair of the tissues which are fully developed is notthe same thing aa the active growth of the body which occurs beforethe adult stage is reached, and that food which is efficacious inthe former may be quite ineffective in the latter condition. Recentwork on metabolism has also shown that man cannot live on proteinalone, even if it is mixed with fat and carbohydrate to supply thenecessary energy, but that there we other organic compounds ofuncertain nature which often in very small quantities are absolutelyindispensable.Another general result of this renewed investiga-tion haa been the discovery that the animal body possesses a powerof syntheeising comparatively simply food material into morecomplex substances, which waa previously considered to be thespecial feature of vegetable life.I propose in the following section to illustrate these t h a w by7 Arch. Pharm., 1912, 250, 252, 389 ; A,, ii, 791, 859PHYSIOLOGICAL CHEMl STRY. 229alluding to the more important papers in the year’s output thatsupport them.I n order to estimate the nutritive value of any article of food,experiments in vivo are absolutely necessary; no amount of merechemical analysis or observations of digestion in vitro are sufficient,however useful they may be as accessory methods of research.Thesort of work on the utilieation of individual proteins which iswanted is well illustrated by that of Mendel and Fine8 on theproteins of various cereals and legumes. Mendel, in conjunctionwith Osborne? has carried the matter further in their extensiveexperimente on rats, and shown that it is possible to keep theseanimals alive for prolonged periods (equivalent to the average lifeof the rat) when a single protein is the sole source of nitrogenoussupply; and it is by means of such observations that they havereached the important conclusion that maintenance and growthare not the same problems.From the wealth of detail which isgiven t o support this contention, I take but 2 solitary example,which is quite typical and obtained from the examination of ananimal higher than a, rat. A gliadin food mixture was given to apuppy in place of its mother’s milk; this produced typical failurein growth, although the mother dog thrived on the same diet andactually produced young, and secreted milk in sufficient quantityand quality to induce normal growth in her offspring. No strongerproof could be adduced of a power to synthesise “ Bausteine ” inthe body which are absent from the food. McCollumlO makesthe useful suggestion, seeing repair processes are of a differentcharacter from those of growth, that in cell katabolism and repairthe processes do not involve the destruction and re-synthesis of anentire protein-molecule ; this is obviously necessary during growth.A similar power t o synthesise lipoids from simple phosphorisedcompounds on a diet free from fats and lipoids was further deter-mined by the same authors.11 But restricting ourselves for thepresent to the question of proteins, one must allude next to a seriesof papers which deal with amin*acid synthesis and the chemicalpossibilities of the transformation within the body of one amine* J.Biol. Chem., 1911, 10, 345 ; 1912, 10, 433 ; 11, 1, 5 ; A., ii, 63, 271, 272.Full details inPublication 156, Part 11, Carnegie Inst. of Washington, 1911; A., ii, 271.Zcitsch.physiol. Chm., 1912, 80, 307 ; A,, ii, 957. J. Biol. Chem., 1912, 12,473 ; A., ii, ,1190. The same note, namely, the different r81e of proteins i nmaintenailce and growth, is struck by McCollum, Amer. J. Phpiol., 1911, 29, 215 ;A., ji, 63. For feeding on single proteins are also Rohmann, Binchem. Zeitsch.,1912, 39, 507 ; A., ii, 462, and Osborne, Mendel, anc! Miss Ferry, J. BWZ. Chem.,1912,13, 233 ; A . , 1913, i, 124.Proc. Amer. physiol. SOC., 1911, xii, Amer. J. Physiol, 29.lo See preceding footnote.l1 Osborne, Mendel, and Miss Ferry, J. Biol, Chcm., 1912, 12. 81 ; A., ii, 779230 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.acid into another. The early members of the series were brieflymentioned in last year's report, and G.Embden12 and his colleagueshave continued the work, and supported their contentions by actualexperiments in vivo (perfusion of liver, etc.). I do not proposehere to repeat the details, the essentials of which have alreadyappeared in our abstracts, but would merely point out that workof this kind is increasing by leaps and bounds our knowledge of theintimate processes of nutrition and metabolism, and demonstratesbeyond cavil the wonderful synthetic powers which animal csllspossess. The liver is credited with the bulk of the work, but thistendency to pile up hepatic duties is somewhat discounted by someresearches to be alluded to a, few paragraphs ahead. Another factorto be reckaned with is insisted upon by the American writers justmentioned, and that is bacterial action.It is quite possible thatsome of the new chemical permutations and combinations are theresult of the activity of micro-organisms in the intestine ; seeingthat bacteria are always with us, this possibility cannot beneglected; but knowing also that it has been shown that healthyanimal life is possible with a perfectly sterile alimentary canal, itis impossible t o resist the conclusion that the tissue cells are moreimportant than these accessory factore.Loewi, Abderhalden,13 and others alluded to in previous reportshave shown that it is possible to maintain animals alive and inhealthy equilibrium by feeding them on the simple " Bausteine "of the food if they are given in appropriate proportions. No one,however, would have ventured t o prophesy that simple ammoniumsalts could replace aminclacids, or could be synthesised into tissueprotein.This, however, appears to be probably true, and the yearjust passed is remarkable for a number of papers on this aspectof metabolism. The principal ones which deal with it are givenin the footnote below,l4 but seeing that the subject is as yet in itsinfancy, one would perhaps be wise a t present to adopt the cautiousattitude of Abderhalden, who draws the general conclusion thatalthough ammonium salts and especially the acetate influence thenitrogen balance, and may lead t o the retention of nitrogen, never-12 Biochem. Zeitsch., 1912, 38, 393, 407, 414 ; A., ii, 278, 279. See alsoAbderhalden and Hirsch on the formation of glycine in the organism (Zeitsch.physiol.Chem., 1912, 78, 292; A., ii, 579.Striking recent experiments of this kind are given by Abderhalden, 'Zeitsch.physiol. Chem., 1912, 77, 22 ; A., ii, 363.14 E. Grafe and Schlapfer, Zeitsch. phpiol. Chem., 1912, 77, 1 ; A., ii, 363 ;E. Grafe, ibid., 78, 485 ; A., ii, 659 ; Voltz, ibid., 79, 415 ; A , , ii, 780;Abderhalden, ibid., 78, 1 ; A., ii, 575 ; Abderhalden and Lamp&, ibid., 80, 160;A., ii, 956 ; Abderhalden and Hirsch, ibid., 136 ; A., ii, 957 ; Ibid., 81, 323 ; A.ii, 1189 ; Abderhalden and Lamp&, ibid., 82, 21 ; A . , ii, 1191 ; Abderhalden andHirbch, ibid., 1 ; A., ii, 1190 ; E. Grafe, ibid,, 347 ; A,, 1913, i, 125PHYSlOLOGICAL CHEMISTRY. 28 1theless the assumption that animal cells can build up proteinfrom ammonia and non-nitrogenous material (carbohydrate, etc.),is not yet proved up to the hilt; it is quite possible that the retainednitrogen may bo in other and simpler combinations than protein.Now let us return to the point about the part played by the liverin such syntheses. I n several previous reports I have dealt withthe question of protein absorption, and have throughout main-tained the position that the complete (or almost complete) cleavageof proteins into individual amheacids in the alimentary canal isfollowed by the absorption of these simple substances into the blood.Those which are of special importance in repairing the tissue waabare seized upon by the tissue cells to which the blood conveysthem, and the unused residue is deamidised, and its nitrogen ulti-mately excreted as urea. Deamidation and formation of ureaappear to be a special function of the liver, and has been generallyassumed to occur rapidly.I have always strongly combated theidea to which Abderhalden among others has committed himself,namely, that re-synthesis of protein from the amino-acids occursduring absorption in the intestinal wall.The work of 1912 has supported these contentions absolutely.I n the first place, Folin and Denis15 have published a most impor-tant set of papers which they have entitled “Protein metabolismfrom the standpoint of blood’ and tissue analysis.” Folin is justlycelebrated for t.he introduction of new and accurate analyticalmethods, and now his newly-introduced methods have been auccess-ful in proving that after the ingestion of proteins, or of amineacids, it is perfectly easy to demonstrate and estimate an increasein the non-protein and amino-acid nitrogen of the blood.A newpoint made out is that deamidation does not occur so rapidly as wepreviously thought it did.These observations have been oriticised in two directions. Folisstated that a certain amount of nitrogenous absorption occurs inthe stomach; London 16 considers this cannot be stated positivelyunless the remainder of the alimentary canal is excluded, forabsorption from the auto-digestion of intestinal juices might con-ceivably be occurring, Folin,” however, has successfully defendedhis own point of view.After all, the point is only a minor one.Speaking personally, I am inclined to think that more accurateconclusions can be drawn from normal animals than from thosewith extensive mutilations such as London employs.The other criticism comes from Abderhalden and Lamp6,18 whol5 J . Biol. Chrm., 1912, 11, 87, 161 ; 12, 141, 253, 259 ; A., ii, 271, 364, 780,l7 J. Biol. CILcm., 1912, 13, 389 ; A., 1913, i, 126.853. l6 Zeitseh. physiol. Che?n, 1912, 81, 283 ; A , , ii, 1189.Zeitsch, physiol. Chcm., 1912, 81, 473 ; A., ii, 1100232 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.also deal with a minor point, namely, a question of chemical tech-nique in the methods used. They suggest a modification for detect-ing amino-acids in the blood. The main importance of thisapparently critical paper resides in the admission that after feedingan animal on meat or on proteolytic cleavage products the blooddoes contain excess of amino-aoids which pass into it direct fromthe intestine.We can only hope that this means that Abderhaldennow definitely abandons his view that protein synthesis occurs inthe intestinal wall.19 The same question is taken up by Buglia,mand he also arrives at the conclusion that synthesis, of protein fromits cleavage products does not occur in the wall of the intestine.Let me conclude this discussion by some quotations from a paperby D. D. van Slyke,21 which puts the problem very well, and showsthat all physiological chemists throughout the world are fallinginto line in regarding the intestinal wall as no specific place forprotein synthesis, and are also beginning to doubt whether themuch-burdened liver has such multifarious duties as those it isusually credited with. He begins by describing a method forestimating amino-acid nitrogen in blood, for van Slyke, like Folin,is fertile in methods.By its use he shows that in fasting animalsthe amount of amino-acid nitrogen is 0*003-0*005 gram per 100 C.C.of blood. Absorption of 10 grams of alanine from the intestineincreases this figure, and in the normal digestion of meat theamount may be more than doubled. The rapidity with which amino-acids disappear from the blood was illustrated by injecting10 grams of alanine direct into the blood+&ream; five minutes lateronly 1.5 grams were left in the blood, and 1.5 grams passed intothe urine; so the remainder must have been taken up by thetissues. The theory that amino-acids are synthesised into blood-protein whilst passing through the intestinal wall therefore becomessuperfluous, and there can be no doubt that they pass as such intothe blood from the intestine, amd then are rapidly removed fromthe blood by the tissues.The liver, moreover, appears to play nospecially active part in picking up these acids; doubtless all thetissues help themselves. This conclusion is based on the observationthat the blood of the femoral artery during digestion containsnearly as much amino-acid nitrogen as that in the mesentericveins.I have elected to devote mmt of the preceding paragraphs in thissection to the proteins, but it must not be supposed that theLQ That Abderhalden was weakening in this view was indicated in a previouspaper (Abderhalden and Kramm, Zeitsch.physiol. Chem., 1912, 78, 382 ; A., ii,574). Here he states that his experiments do not contradict the theory.20 Zeitsch. Biol., 1911, 57, 365 ; 1912, 58, 162 ; A., ii, 182, 462..J. Biul. Chem., 1912, 12, 399 ; A., ii, 1184PHYSIOLOUICAL CHEMISTRY. 233problems of nutrition and of synthesis in the body are not alsoequally interesting in relation to carbohydrates and fats.Exigencies of space, however, preclude more than a passing refer-ence to these. In fact, I shall confine myself to two subjects only,one of which is connected with carbohydrate metabolism, and theother with one of those unknown but indispensable components ofa healthy diet to which I referred in the opening paragraph of thissection.GZycoZysis.-The disappearance of sugar from the body, and itsultimate oxidation with the formation of carbon dioxide and water,is a question of unusual interest, not only because the intermediateproducts are matters of discussion, but chiefly because the internalsecretion of the pancreas is believed to play its part in glycolysis.Of the various tissue cells investigated by Levene and Meyer,B onlyone species hitherto has shown itself capable of causing glycolysis,lactic acid being an intermediate stage in the combustion of sugar;these cells are the leucocytes of the blood.It is, however, wellknown, as was first demonstrated by 0.Cohnheim, that the com-bined action of muscular tissue and pancreatic extract causes sugaradded to the mixture to disappear. Knowing, moreover, that sugaris the main source of muscular energy, the phenomenon wasexplained by supposing that the normal action of the internalpancreatic secretion on reaching the muscles was to facilitate thecombustion of sugar; and the absence of that secretion after extir-pation of the pancreas explained the accumulation of sugar and theoccurrence of a diabetic condition. This view will certainly haveto be revised in the light of Levene and Meyer’s recent workF3 iftheir discovery is confirmed, and one cannot at present see any flawin their methods. The sugar certainly disappears, but it is notburnt up into oxidation products; in other words, sugar disappear-ance is not glycolysis in the usual acceptation of the term. Thedisappearance of the sugar is due to condensation into a poly-saccharide, and the sugar can again be recovered after hydrolysiswith acid.Here, indeed, we have a riddle that badly needs aguesser.Accessory Factors in Normal Dietaries.-The reader will nothave failed t o notice in this report how largely America has figuredin the research of the year. I attribute this largely t o the wisdomof our Transatlantic cousins in providing adequate endowment forresearch, so that the ablest and keenest of American minds meattracted to devote themselves to what is under usual conditionsunremunerative labour. My insular prejudices, however, lead me22 J.Biol. Chem., 1912, 11, 361 ; 12, 265 ; A., ii, 577, 852.23 Ibid., 347 ; A., ii, 577234 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.to congratulate myself that I am able in concluding this section toallude to an important metabolic research by a f ellow-countryman.F. G. Hopkins was one of the earliest to recognise the importanceof what for want of a better name we term the accessory factorsin a dietary; and the effect of quite small quantities of suchsubstances is admirably illustrated in his most recently publishedpaper.24 Groups of young rats were fed on a basal diet of casein-ogen, fat, carbohydrate, and salts, and compared with other ratson the same diet plus a minute ration of fresh milk.The formersoon ceased t o grow; the Iatter grew normally. The consumptionof food was practically the same throughout, but the milk adden-dum reduced the food necessary for a given increment in weightt o one-half or less. Cessation of growth occurred before loss ofappetite appeared. What the actual substances are in the milkwhich thus markedly, although in a secondary way, affect growthis not yet known.Beri-beri. Polyneuritis.The importance of minute quantities of certain materials in thediet is well exemplified in the causation of that terrible disease ofthe East known as beri-beri. The interest of the subject leads met o supplement what I said last year on this disease, and to breakthrough my usual rule in not taking up the same subject two yearsin succession.It may now be taken as proved that the diseaseis usually produced by a diet of polished rice, that is, rice deprivedof its outer layer in which the anti-neuritic substance occurs. Itcan be cured by the administration of the polishings, or of theactive substance separated from them. The rapid progress made inthe discovery of the cause, and the cure of the condition illustratesthe usefulness of animal experimentation, for the disease can beeasily oaused in birds, and now it can be as easily cured. CT. Funk,who was the firat actually to separate out the anti-neuritic prin-ciple, which he terms vitamine, has not yet fully made out itschemical composition, but he states in his latest paper25 that itsproperties suggest it is a pyrimidine base, and forms a constituentor derivative of nuoleic acid, For curing pigeons of polyneuritis,doses of 0.02 to 0.04 gram given by the mouth are sufficient. Thesame base he also separated from yeast, ox-brain, milk, and possiblyfrom limejuice.Schaumann’s hypothesis that a deficiency oforganically combined phosphorus in the food leads to a similarpoverty of phosphorus in the body, and thus to neuritis is therefore24 J. Physiol., 1912, M, 425 ; A . , ii, 779.z5 Ibid., 1912, 45, 75 ; A, ii, 856PHYSIOLOGICAL CHEMISTRY. 23 5not confirmed, and H. Wieland26 arrives at a similar conclusionfrom his experiments on mice.27Moore, Edie, and others28 a t Liverpool have also separated outthe base, and have used yeast as the material to work with.Theysuggest the name tordin. On treatment with barium hydroxide itgives off trimethylamine, and they ascribe to it the formulaC,H,,O,N,HNOs. They are, however, continuing the investigation,and the elucidation of the actual chemical composition of the basecan only be a matter of time. The important practical point isthat its existence and action have been proved.The amouut of vitamine in various articles of food has beendetermined by ascertaining how much of each must be added to adiet of polished rice in order to prevent in birds the occurrence ofpolyneuritis.28a It was found that the anti-neuritic material isirregularly distributed amongst the foodstuffs ; thus 20 grams ofbeef daily were necessary; about half this amount of sheep’s brainproved to be sufficient, and among the animal foods examinedegg-yolk was the most efficient, 3 grams being the necessary dailydose.Amongst the vegetable foods, the efficiency of lentils andunhusked barley were about equal to egg-yolk, but, of all others,yeast was the most efficient in preventing the disease, only 0.5 grambeing enough.The question will doubtless be asked, especially by sufferers fromneuritis, is this discovery of any use to them. The proof of thepudding will be the eating thereof,.and there appears no reasonwhy they should not try. Vitamine is, a t any rate, quite harmless,but whether it will be of widespread therapeutic value is anotherquestion. A cure which is scientifically sound is one thatremoves the cause of the ailment.In beri-beri, a disease due tolack of the base, the cure by the administration of the base istherefore only common sense. But neuritis is caused in other ways,by pressure on a nerve, by inflammation of the sheath of the nerve,and so forth. There is no reason t o believe that in this countrythe sufferers have been on a diet free from or even poor in thisparticular substance. So that although we may hope that thegiving of the drug may assist in alleviating the condition, it doesnot strike a t the root of the miachief, and so one must be verycautious in holding out hopes of any great relief.26 Arch. expt. Path. P?Larm., 1912, 69, 293 ; A., ii, 9152.5 The contradictory results of observers iu their attempts to cure polyneuritiswith lecithin is due to the fact that lecithin is often contaminated with vitaminewhen prepared from animal organs (H. Maclean, Bio-Chcm.J., 1912, 6, 355 ; A,,ii, 1192). 2a Bio-Chetn. J., 1912, 6, 234 ; A,, ii, i 9 4 .an E. A. Cooper, J. Hygicne, 1913, 12, 436236 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.A very remarkable cam of beri-beri has recently been describedby V. L. A n d r e ~ s , ~ ~ in which rice played no part. It occurred ina suckling infant of a Philippine mother, and was cured by with-holding from it the milk of its mother. Analysis of the milkshowed nothing noteworthy in its general composition ; the calciumand phosphorus were even higher than usual. Yet there must havebeen a failure of some substance in the milk, presumably of thevitamine, which is a normal constituent of that fluid; young dogswere fed upon it, and all of them developed peripheral neuritis,Edema, and dilatation of the right side of the heart; in fact, all thesymptoms typical of beri-beri.Such cases as this widen the outlook and form a useful comment-ary on the remarks just made concerning the multiplicity of causesthat may lead to the development of the neuritic condition.In concluding this section, I may mention the very useful term“ deficiency diseases,” introduced by Funk for beri-beri, scurvy,pellagra, and a few other pathological conditions due t o defectivediet.Coagulation of the Blood.The theory most in vogue at present to account for the pheno-menon of blood-clotting is that of Morawitz; and this theory is anamplification of Hammarsten’s, which in its original form postu-lated the existence of two factors; one of these is fibrinogen, aprotein substance in solution in tlie blood-plasma, and the other isan agent which is liberated by the disintegration of the corpuscularelements of the blood, and which on account of its enzymelikecharacters was called fibrin ferment, or thrombin.The action ofthrombin on fibrinogen resulted in the formation of fibrin fromthe latter. Hammarsten even in his earlier papers noted thatcalcium salts favoured congulation, and the prime importance ofsuch salts was fully demonstrated by the subsequent work ofPekelharing, Arthus, and others, who showed that coagulation couldbe entirely prevented by decalcifying the blood by the addition ofsmall quantities of a soluble oxalate.The analogy between blood-clotting aad milk curdling by rennet suggested that the part playedby calcium in both processes was identical. It has been proved thatthe clot in milk is a calcium caseate, and at first it was supposedthat fibrin was a calcium compound of fibrinogen. But it was soonfound that this is not the case. The part played by calcium in theclotting of blood is in the production of the thrombin, and not inthe subsequent action of thrombin on fibrinogen. Like otherenzymes, thrombin has an inactive procursor, which has receivedgg Philippine J. Sci.I 1912, 7, 67PHYSIOLOGICAL CHEMISTRY. 237the name of prothrombin, and what the calcium does is to convertthis zymogen into the active enzyme.Fibrinogen, prothrombin, and calcium are not, however, the onlythree agents which participate in the phenomenon; and it was thespecial feature of the theory of Morawitz that he assumed theexistence of an organic activator which has since received severalother names, but which is usually spoken of as thrombokinase.Much in the same way as the inactive trypsinogen of the freshlysecreted pancreatic juice requirN to be activated by the enter+kinase of the intestinal juice, so it is supposed that the thrombo-kinase acts in conjunction with calcium in the liberation ofthrombin from its mother substance prothrombin.Thrombokinaseor an analogous substance is also provided by the disintegrationof other tissues.It is well known that if blood when shed is allowedto come in contact with other tissues, such as the muscles andskin which are cut through, its coagulation is hastened. Evenalthough this is prevented by collecting the blood straight from anartery through a clean glass tube, it clots in time, and so thethrombokinase which is assumed to be necessary was furtherassumed to originate from the blood-corpuscles.Of the four fibrin factors, two therefore are present in the fluidpart of the blood, namely, fibrinogen and the calcium, and theother two (prothrombin and thrombokinase) are furnished by thecorpuscles, and especially by the blood-platelets.About this date, researchea on immunity were in full swing, andthe ideas current in that region of work were reflected in thetheories put forward concerning the action of enzymes generally.The matter was therefore complicated by the discovery of anti-enzymes. The special one in the blood which keeps it fluid underliving conditions was dubbed anti-thrombin, and according to someobservers, the assumption of an anti-kinase was also necessary.Whether the blood remained fluid, or set into a coagulum wastherefore the resultant of the action of opposing forces, some ofwhich favour the interaction of thrombin and fibrinogen, and othersof which inhibit that action.Quite a t an early stage in the development of these new ideasLeo Loeba put forward other views, especially in relation tothe part taken in the procetw by tissue extracts, and he consideredthat the coagulins of the tissues as he termed them were not merelyactivators, but entered into the actual process of fibrin-formation.An entirely new note in criticism was struck by Rettger, whoworked with Howell, and subsequently by Howell 31 himself.Theseobservers put forward grounds for believing that thrombin is not30 See Ann. Report, 1905, 180. [bid., 1910, 189238 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRS.an enzyme after all, for they found a definite quantitative relation-ship between the interacting substances, a fact which is not inaccord with the conception of the ferment-like character ofthrombin, and during last year H. Stromberg 32 supported Howell’sview. The idea that thrombin is not an enzyme has provoked muchreflection and criticism among physiologists, although, so far as Iknow, no one has yet got so far as to repel or even attack it inprint.A complicated question of this kind is not susceptible ofacademic discussion without facts to go upon, and facts take timein working out. So far, however, physiologists as a whole are notyet convinced, and still teach that thrombin is an enzyme. If infibrin formation we had only to deal with two reacting substances,thrombin and fibrinogen, the problem would be a simple one, andcould be easily settled, but when the factors are more numerous thedifficulties are increased. It is admitted by all that thrombokinaseunder one or other of its numerous aliases, whatever may be itsaction, is not an enzyme, and it may be that it was the action ofthis substance which complicated Howell’s results.The papers on the subject, published in the year 1912, havemainly emanated from Baltimore; thus Meek33 has taken up thequestion of seat of origin of fibrinogen.Dogs were bled, the bloodwhipped, and then re-injected minus its fibrin. The regeneration offibrinogen occurred with great rapidity, 100 per cent. increasebeing noted in three hours. If the liver was entirely excluded fromthe circulation, however, regeneration did not take place a t all, andthe small amount of fibrinogen left in the residual blood rapidlydisappeared. A hasty observer would have a t once jumped t o theconclusion that the liver itself forms fibrinogen, but experiencebreeds caution, and, as Dr.Meek states, there is still open anotherpossibility, namely, that the liver may influence the formation offibrinogen elsewhere by means of a hormone.The work of BayneJoness emphasises the importance of theblood-platelets in providing the corpuscular contribution to fibrinformation. He found in his experiments with platelets and puresolutions of fibrinogen that the former contain a substance, pro-thrombin, which after activation with calcium, clots fibrinogen.This is a confirmation of Morawitz’s views. He also found thatextracts of platelets cause the clotting of “peptone plasma,” a32 Biochem. Zeilsch., 1911, 37, 177 ; A,: ii, 59.33 Proc. Amer. physiol. SOC., 1911, xix, Amer. J. Yhysiol., 29 ; A., ii, 273.34 Amer. J.Physiol., 1912, 30, 74 ; A., i, 459. Cramer 2nd Pringle reached thesame conclusion by a different method, for they found that after removal of theplatelets by filtration through a nerkfeld filter from oxalate plasma, coagulationcan no longer be induced by the addition of calcium salts (PTOC. yliysiol. Soc., 1912,xi, J. Physiol., 45)PHYSIOLOGICAL CHEMISTRY. 239form of plasma which already contains thrombin, fibrinogen, andcalcium. The platelets are therefore the source of the fourthfactor, whi‘ch Morawitz would term thrombokinase, but whichBayne-Jones, using Howell’s nomenclature, prefers to call thrombo-plastin. H e explains the absence of clotting in peptone blood asdue to the presence of large amounts of anti-thrombin, and theaction of thromboplastin is t o neutralise the antithrombin.The question of antithrombin also is taken up by D.Davis.35 Hefound, as many have found before him, that injection of thrombininto the blood-stream within certain limits does not produce intra-vascular coagulation, and considers that the injection excites therapid formation of its antidote, the agent which normally preventsclotting during life.The general idea that thrombokinase is not an activating agent,but is the antagonist of antithrombin, is more fully advocated byHowe11,36 under whom both Davis and Cecil worked. Later in they e a r s he brought forward some more evidence in favour of thisview, and supplemented it by hazarding an opinion of the actualnature of thromboplastin. He considers that it is a phosphatideof a nature akin to kephalin.H e thus revives an old notionoriginally promulgated by Wooldridge many years ago. WhenWooldridge worked our knowledge of the phosphatides and lipoidsgenerally was very scanty, and the nucleo-proteins were almostunknown. When, therefore, Wooldridge spoke of lecithin as ahelp to blood-clotting, he exercised not only a tenable view of theprocess, but if Howell is correct he showed a truly propheticinstinct.Quite independently of Howell and his pupils, much the sameview has found favour with E. Zak.B He finds that a diminutionof the lipoids of the plasma leads to a delay in its coagulation, andthat the addition of phosphatides from other organs acts even morestrongly in hastening coagulation than those normally present inthe blood.Alkaloids which unite with lecithin are also inhibitoryto coagulation. Such results agree with the views of AlexanderSchmidt on zymoplastic substances, and if correct render theassumption of a, kinase in Morawitz’s sense unnecessary.We thus see that the problem of blood-clotting has entered on anew phase, and is in a more interesting condition than it has beenin for many years past.35 Amer. J. Physiol., 1911, 29, 160 ; A . , ii, 60. A papor prcceding this (ibid.,156 ; A., ii, 60) by Cecil contains many valuable hints for the purpose of obtaiuiiigand preserving pcptone plssnia and thromboplastic extracts.d(i Ibid., 187 ;A., ii, 60.38 Arch. expt. Path. Phnrm., 1912, 70, 27 ; A . , ii, 1065.37 Ibtd., 1912, 31, 1 ; A , , ii, 1078240 ANNUAL REPORTS ON TEE PROCIRESS OF CHEMISTRY.Oedema.The cedematous or dropsical condition is due to an abnormallylarge formation of lymph, the fluid which leaks from the blood asit passes through the thin-walled capillaries, and is thus an exag-geration of a normal process.It can be produced by an increaseof the capillary pressure, it9 when one ties a ligature around a, limbso as to obstruct the venous outflow. It can be also produced byan injury to the capillary epithelium, which renders the vessel wallsmore leaky. Another factor is doubtless a change in the blood,such as an increase in its water, or the development of poisonswhich, circulating in the blood, lessen the vitality of the capillarywalls, Carl Ludwig taught that increased lymph formation wasthe result of purely physical factors of this nature, and the sameposition has more recently been maintained by Starling.Heidenhainintroduced the so-called ‘‘ vital theory,” in which he bestowed uponthe living cells of the capillary wall a selective power which enablesthem actually to secrete lymph; he was further the inventor of theword lymphagogue (or lymph driver), which he applied to variouschemical agents, many of which he considered increased the lymphby stimulating the capillary cell to heightened secretory activity.Pathologists have for long wrangled over the question of therelative merits of the mechanical and vitalistic hypotheses, andthe mechanical theorists have differed according as to whetherpressure variations, cell-permeability, or blood changes such a.eihydmmia are the more potent in the causation of the condition.Non-partisan onlookers have agreed that in different cases thesevarious factors may have different values, and although most exhibitscepticism regarding Heidenhain’s extreme views, they are never-theless quite open to conviction that the cells may possibly exercise,thin though they are, a certain amount of selective action.In 1910, however, Martin Fischer, of California, published abook 39 which rather fluttered the dovecotes of the pathologists, forit denied that any of the factors mentioned were of any real conse-quence a t all, or, a t any rate, were quite insignificant in comparisonwith a new power which he considered his experiments taught himwm the main motive force in attracting fluid from the blood intothe tissues.He found by experiments on various colloids thatacidity caused them to swell more when immersed in watery fluidsthan when the reaction was neutral. Dead frog’s legs which hadbecome acid similarly absorbed more water; and put in baresta9 “CEdema,” S. Wiley and Sons, New York. See also Zciklch. Chem. Itid.Kolloide, 1911, 8, 159 ; d., 1911, ii, 309 ; Koll. Chcm Beihefte, 1911, 2, 304 ; A , ,1911, ii, 610PHYSIOLOGICAL CHEMISTRY‘. 241outline his theory of edema is that increase in the acidity of thetissues which is the result of many pathological processes causesby osmotic pressure water to be drawn from the neighbouring blood-stream. I think physiologists all felt when they read Fischer’svery clear and well-argued statements that here, at any rate, wasa new light on what is certainly a puzzling problem, but theywere not prepared to accept fully the sweeping conclusions he drew.A palpably weak point that immediately attracted notice was theadmission that an alkaline reaction was almost as potent as anacid one in promoting the swelling of colloids; and I fancy manyfelt that the experimental data, were hardly sufficient to supportall his contentions. During the present year several papers haveappeared which contest the new views; for instance, Pincussohn 40found that many tissues behave exactly in the contrary waytowards acid from what Fischer found. Gelatin, muscle, andcartilage swell more in acid, but liver, spleen, kidney, and lungdo not. It is quite evident that a rule which is not universallytrue cannot be of prime importance. A. R. Moore41 is still morepositive that Fischer is incorrect. Gies 42 severely criticises thetheory, while he does not deny the possibility that tissue changesmay have an influence; he takes the view that protein cleavageproducts, the result of the action of tissue proteases, may baefficient water attractors, but admits that up till now this has notbeen proved. Fischer 43 has defended his views, but the attackupon them has been sufficiently serious to make physiologistsdoubtful whether they can be accepted without very considerablereserve.I take the present opportunity of correcting a slip that occurredin my report of last year. Speaking of acapniu, I stated that theword had been introduced by Dr. Yandell Henderson. Dr. Hender-son has certainly made the word familiar, but as has been pointedont to me, he did not himself coin it. The late Professor AngeloMOSSO, of Turin, was the author of the word; in his “Life on theHigh Alps ” (1898) he says : “ As the ancients were not acquaintedwith carbonic acid, and had therefore no name for it, I chose theword smoke as most resembling it in a physiological sense, and socoined the word ‘ acapnia,’ which means without smoke.”W. D. HALLIBURTON.JO Zeitsch. expt. Path. Ther., 1912, 10, 308 ; A., ii, 666.41 Pflilger’s Archiv, 1912, 147, 28 ; A , , ii, 856.42 Biochem. BuZl., 1912, 1, 461 ; A., ii, 856 ; Ibid., 540 ; d., ii, 1080.43 Zeitsch. Chm. Ind. Kolloide, 1912, 10, 283 ; A . , ii, 784 ; Biochem. Bull.,1912, 1, 441 ; A., ii, 856.REP.-VOL. IX.