130 Mr Hermann on the Changes the Animal 



Blood during Cholera. — In this disease the blood is known to 

 be of a very dark colour, and thick consistence. Mr Hermann 

 obtained the blood of a patient who had laboured under a very 

 severe attack of cholera for a few hours. The blood was drawn 

 four hours before death, after violent vomiting. 



In 100 parts of blood there were forty of serum, and 60 of 

 clot; consequently 17 more of clot than in the healthy condi- 

 tion. The specific gravity of the serum was 1.036, and this 

 fluid was decidedly alcaUne, The clot was acid. 100 parts 

 boiled with the carbonate of baryta, as before, evolved 21.2 of 

 gaseous carbonic acid, exactly the same quantity as was obtained 

 from the clot of healthy blood. 



Mr Hermann conceives that this separation of the blood into 

 an acid clot and alcaline serum, is owing to the property which 

 the fibrine has of absorbing a certain quantity of acid ; and he 

 considers it as a phenomenon analogous to the change which 

 weak acids undergo, when wood is immersed in them ; the wood 

 absorbing a considerable quantity of the acid. Should, then, 

 the whole quantity of acid in the blood be diminished, the fibrine 

 still retains a certain portion of it ; and, if the diminution be 

 very great, the whole of the acid of the serum may be removed, 

 and this fluid will consequently exhibit alcaline properties, in 

 consequence of the presence of subphosphate of soda in it. 



The alcaline reaction of the serum in blood of those affected 

 with cholera, is a very constant appearance. It only begins im- 

 mediately after the patients have had evacuations by vomiting; 

 and it again disappears when the patient survives the attack. 



The following Table exhibits the differences observed by Mr 

 Hermann in the composition and properties of healthy and dis- 

 eased blood. 



