54 GASTRIC JUICE. 



Beaumont was the first who observed that non-coagulated 

 albumen also undergoes a change on the stomach, while Tiede- 

 mann and Gmelin, and subsequently Blondlot, believed that they 

 had arrived at the opposite conclusion, from their experiments. 

 Any one may, however, very easily convince himself that the 

 blood-serum and the albumen of eggs when stirred with water and 

 filtered, are rendered as strongly turbid by the gastric juice as by 

 any other dilute acid ; the gastric juice, whether it be natural or 

 artificial, often exerts little or no further influence on the albumen, 

 when its digestive power is gone in consequence of the partial or 

 total loss of the free acid. If, however, we again add fresh acid, 

 we perceive the gradual conversion of the albumen in the diminu- 

 tion of the quantity of the coagulable substance, unless, like 

 Blondlot, we use too small a quantity of gastric juice for the albu- 

 men ; finally, the fluid ceases to give any trace of ordinary albumen, 

 either when boiled, or on the addition of nitric acid or of any other 

 test. The same process may be observed in natural digestion. If, 

 for instance, we observe the contents of the stomachs of dogs with 

 a gastric fistula, after they have swallowed such solutions of albu- 

 men, we find that the contents at first have only a slight acid 

 reaction. (Whether they are clear, or turbid from the partial pre- 

 cipitation of the albumen, is a point which cannot be decided, in 

 consequence of the invariable presence of mucus.) Very soon, 

 however, after from 5 to 10 minutes, so much gastric juice has 

 been secreted, that the alkali of the soluble albumen is not merely 

 saturated, but the whole digestive mixture has assumed a strong 

 acid reaction. Here also we may observe a gradual diminution of 

 the coagulable matter ; but I will not venture to deny that a part of 

 the albumen may pass in an uncoagulated condition into the small 

 intestine, in a state of health, as has been observed by Tiedemann 

 and Gmelin. Mialhe* has also convinced himself of the metamor- 

 phosis of soluble albumen during gastric digestion. In relation to 

 the products of the digestion of soluble albumen, I have been unable, 

 with the means we at present possess of analysing such com- 

 plex bodies as the protein-compounds, to discover any difference 

 between the peptones of soluble and coagulated albumen. 



Schwann, in accordance with the ideas and nomenclature of 

 that day, gave the names of osmazome andptyalin to the substances 

 which resulted from the digestion of albumen ; Mialhe was the 

 first to discover that a single, easily soluble substance, is pro- 

 duced from the digestion of albumen or other protein-bodies, and 

 * Journ. de Pharm.et de Chim. 3 S6r. T. 10, p. 161.167- 



