CONVERSION OF PROTEIN-BODIES INTO FAT. 215 



that physiologist, introducing into the abdominal cavity of pigeons 

 portions of albumen or crystalline lenses enclosed in gutta percha 

 bags. These experiments, in which there was only a very small 

 increase of fat where the gutta percha bags were well preserved, 

 seem rather to speak against the formation of fat than to confirm 

 such a view. Schrader* employed crystalline lenses inclosed in 

 stoppered glass tubes for similar experiments : he did not, how- 

 ever, make any quantitative analyses, but merely thought he had 

 discovered the presence of fat by examination with the microscope. 

 F. W. Burdachf has recently carried on some very circumstantial 

 experiments, in which according to Wagner's method, portions of 

 albumen or crystalline lenses, inclosed in collodion or caout- 

 chouc, were introduced into the abdominal cavity of animals, 

 and examined after an interval of a month or even a longer 

 period of time ; from these observations Burdach convinced 

 himself that where the animal juices were entirely cut off, the 

 protein-body was not metamorphosed into fat, nor did it 

 undergo any essential alteration from the simple action of the 

 animal heat; whence it followed that if the protein-substances are 

 actually converted into fat within the animal body, the free access 

 of animal juices is at all events indispensable to the process. Bur- 

 dach also found that when the albuminous substances were enve- 

 loped in collodion, a very fatty yellowish layer of exudation was 

 formed upon the latter, in consequence of the exudative inflam- 

 matory process, in precisely the same manner as when such a mass 

 is deposited directly upon the protein- substance. It is, therefore, 

 obvious that the yellow fatty rind observed in Wagner's experi- 

 ments is not the result of the decomposition of the protein- 

 substance, although it is possible that the whitish fat which appears 

 as if infiltrated into the object (but seems to be always more 

 copiously deposited on the circumference than at the centre) 

 may derive its origin from the decomposition of the protein-body. 

 With the view of determining this question, Burdach employed 

 porous vegetable matters, such as wood and elder-pith in place of 

 the protein-substances in his experiments, and the results obtained 

 were very nearly the same as those observed in the case of nitro- 

 genous animal matters, the yellow fatty exudation being deposited 

 round these substances, and the fat having been imbibed, through 

 the intercellular spaces of the periphery, into the innermost part 

 of the wood or elder-pith. 



* Gottinger gel. Anz. 1853. No. 5. 



t Dissert, inaiig. med. Regimontii, 1853. 



