34 



PHYSIOLOGY 



CHAP. 



carried out with better defined products, 

 results shown in the following table : 



He obtained the 



These results show that while the two protoalbumoses afford a 

 perfect substitute for meat, this is not the case with hetero- 

 albumose. According to Blum this difference is due to the absence 

 in the heteroalbumose of those molecular groups necessary for 

 assimilation which are found in the protoalbumoses, groups 

 probably represented by indol. These compounds are, as a matter 

 of fact, poorly represented in heteroalbumose, in which, on the 

 other hand, the glycocol groups abound. At the same time the 

 researches of Henriques and Hansen have shown that in mice 

 heteroalbumose not only economises the consumption of albumen, 

 but may even be substituted for it altogether. 



(&) Gelatine which, as is well known, is obtained by boiling 

 down the connective tissues (Papin, 1682) is a modification of 

 albuminous substances which, when cold, forms a hydrogel, which 

 can be peptonised like albumens. Its nutritive value has been 

 much discussed. 



At the time of the French Eevolution the method of extracting 

 gelatine was perfected with a view to improving the nutrition 

 of both troops and populace, and it was looked upon as most 

 nutritious, a committee of the Institut de France having declared 

 it to be so. Gelatine soups were consequently given to hospital 

 patients, but experience made doctors abandon their use, as they 

 produced nausea. 



In 1831, Donne made experiments with gelatine on himself and 

 on dogs, giving the dogs 20-50 grms. of gelatine and 85-100 grms. 

 of bread per day. He found that the dogs wasted away, but this 

 was clearly due to their food being insufficient. Edward and 

 Balzac also observed that dogs fed on gelatine wasted away, but 

 they found that this was less noticeable when bread was added to 

 the diet of gelatine. 



In 1841 the French Academy appointed another committee to 

 settle the disputed point. Magendie, who drew up its report, 

 came to the conclusion that dogs cannot be fed on gelatine ; that 

 they will waste away even when bread and meat are given in 



