PHYSIOLOGY. 



737 



arc primary product*, *nd 



in. in i In- ihinl product, gelatin-peptone, by l- 



ing precipitated by sat unit ion with ammonium 

 fOTpnate. The priiniiry products by further fer- 

 ment action an- gradually changed mi., true 

 pi-pli'iii 1 . 1 In- prut 11 pa-sing tirst through the stage 

 <it deutero. Owing ti> th<- difficulty of sepa- 

 rating lti' aiiiinoiiiiini sulphate completely from 

 tin' peptone, the latter could not l>e obtained in 

 siillicient (]uantity and in a sufficient state of 

 purity for analysis. The gclatoses are readily 

 oluble in eold water, are slowly diffusible, and 

 in composition resemble gelatin itself. They 

 are supposed to be formed by hydration. but 

 their cncmieal composition affords no evidence 

 nf this view. 



Recapitulating the results of their experi- 

 ments on the action of saltson heat coagulation, 

 Sydney Kinger and Harrington conclude that 

 lime and the allied elements favor the heat co- 

 agulation of the proteids of serum. A similar 

 action is exerted by magnesium sulphate. It is 

 of interest to note that in the process of coagu- 

 lation by heat, as in the process of spontaneous 

 clotting of blood, and the clotting of milk to 

 which rennet has been added, lime plays an im- 

 portant part. This similarity of behavior holds 

 for barium and strontium, and is believed to be 

 generic, for the reason that the influence of the 

 same elements upon heat coagulation appears to 

 belong to their salts generally. One is led to 

 infer a possible likeness in nature between heat 

 coagulation and spontaneous clotting of proteid 

 bodies. Hut that there are differences between 

 heat coagulation and spontaneous clotting we 

 learn from the fact that in the former the solu- 

 tion becomes more alkaline, whereas in the lat- 

 ter, as also in the stiffening of muscle in rigor 

 nitirfi/f, there is a development of acid. It has 

 further been shown that a certain amount of 

 antagonism exists between potassium and sodi- 

 um chloride on the one hand and lime chloride 

 on the other. 



The following are the results of the researches 

 of L. Huiruoneiiii on the influence of wines on 

 pepsic digestion: All wines interfere with the 

 action of pepsin, those richest in alcohol, cream 

 of tartar, and coloring matter being most in- 

 jurious. Among the elements of natural wine 

 the coloring matters act in concert with the al- 

 cohol and the cream of tartar to arrest pepsic 

 digestion. The acidity of normal wines can not 

 excite the action of pepsin, and in most cases it 

 does not appear to assist. Among the coloring 

 matters introduced fraudulently into wines, 

 iiicthylene blue, azoflavine, solid blue, and ma- 

 genta interfere with pepsic digestion. The veg- 

 ctable colors, black mallows, elder-berries, and 

 maki. like a-nolinc. exert an injurious action. 

 Plastering, by removing a part of the cream of 

 tartar, eliminates an element of natural wines 

 which retards the action of pepsin in ri/rn.' Di- 

 gestion is more rapid in presence of plastered 

 wines than of natural wines, but the advantage 

 which plastered wines have in this respect does 

 not conceal their other disadvantages. 



Experiments by T. Lander Hrunton and S. 

 Mart in on the action of alcohols and aldehydes on 

 protcid substances indicate that the higher alco- 

 hols in the series have a less powerful action in 

 precipitating and coagulating proteids than the 

 VOL. xxxi. 47 A 



lower ones. Allvl alcohol is an exception. Ii in 

 a powerful coagulant of egg albiiineii, and U the 

 only alcohol that coagulate* alhiirnoae*. 



Concerning the relation of the salts to eauein. 

 Soldner starts with the observation that the 

 basis of the a.sli of milk can not be neutrali/ed by 

 the acids present, as the arnpholeric reaction of 

 the milk reipiires. He shous that ii-'i p<-rccnt.<.f 

 the phosphoric acid comes from the phosphorus 

 of the casein or its nucli in, and is preformed in 

 the milk. Casein behaves like an ncid. iniiMiiiit h 

 as it may form salt-like combinations with al- 

 kalies, two of which Soldncr was ttl.le to disiin- 

 guish as neutral or basic calcium com|.oundH. 

 The neutral compound is probably present in 

 the milk. The existence of various organic acids 

 ill the milk is also probable. The calcium salts 

 play an important part in lx>iling and in the cur- 

 dling process. Heated milk shows a more marked 

 increase in alkaline reaction which loses itself on 

 cooling, but all feebly alkaline liquids do the 

 same. It is not true that boiled milk can not be 

 curdled with rennet. The process is much slower, 

 because a portion of the essential calcium salts 

 has been changed by heat to insoluble tricalciurn 

 phosphate. The addition of alkali has a similar 

 action. Introducing an acid to make the phos- 

 phate soluble brings back the curdability. In the 

 same sense the addition of calcium chloride 

 hastens the curdling. 



An examination of what are called peptonized 

 foods Benger's peptoniml beef-jelly. Darby's 

 fluid meat, and pcptoni/ed milk having been 

 selected for the purpose bv P. Horton-Smith, 

 resulted in the conclusions that these foods con- 

 sist really for the most part of albumoses, though 

 they contain also a varying amount of true pep- 

 tone. They can not. therefore, entirely relieve 

 from work the digestive organs; and. also, that 

 the ingestion of large quantities of albumoses and 

 peptones does not disarrange the metabolism of 

 the normal body. 



The studies of M. Van Puteren on the digest- 

 ive processes in infants have shown that the con- 

 tents of the stomach remain in a condition to be 

 pumped out for an hour and a half after a meal, 

 the quantity diminishing rapidly after the first 

 hour; that the acidity of the infant stomach is 

 much less than that of the adult stomach ; that 

 the antifermentative action of the gastric juice 

 seemed to be exceedingly feeble; that the milk- 

 curdling element (called rennin by Foster) was 

 absent in children up to twenty-four days, and 

 could be definitely demonstrated only at from 

 thirty to forty dttvs of age. 



Prom the results of three decril>ed experiments 

 the conclusions are drawn by K. II. Chittenden 

 that alcohol in the quant it ies employed by the ex- 

 periment ers. and in the case of dogs, lias no very 

 striking specific action upon the general metab- 

 olism of proteii'. matter; and that, so far as its 

 general influence on proteid metaliolisni is con- 

 cerned, it nets in the main simply as a non-nitrog- 

 enous food. As such it would yield a certain 

 amount of energy by its own oxidation. and thus 

 tend to protect slightly the consumption of pro- 

 teid matter, and hence conserve the tissues. As- 

 suming this view to be correct, one could not 

 expect any very great diminution in the nitrogen 

 output under the influence of alcohol. At ihe 

 same time, it must be remembered that alcohol 



