100 HISTORY OF GEINE. 



caseine, or flesh, white of egg, and curd of milk. These are 

 identical in composition, modifications of a common princi- 

 ciple to which the name, proteine, is given by Mulder, its 

 discoverer. It is not among the least curious of his results 

 that proteine is^ by weak acids, changed into humate of 

 ammonia, its acid being perfectly identical with that from 

 sugar. In 1838, Prof. Plitchcock, in his report, published 

 the following extract from one of the author's letters, when 

 speaking of geine as the product chiefly of vegetable matter, 

 it was added : " Animal substances aflbrd a similar product, 

 containing nitrogen." The author supposed at that time that 

 the nitrogen in geine was of animal origin ; but since it has 

 been proved that proteine is derived from vegetables, the 

 results of its decomposition by Mulder, leave no doubt that 

 the proteine of vegetables is the source of the ammoniacal 

 compounds of geine found in soil. That neither Mulder nor 

 Berzelius have the slightest doubt that these ammoniacal 

 compounds are wholly distinct from crenic and apocrenic 

 acid, is evident from the care of Mulder to separate these 

 last from the soil, and from the total silence of Berzelius 

 respecting any mistake he may have been supposed to com- 

 mit, by confounding geine with them. 



It will be seen from the account of Mulder's researches, 

 that geine is produced chiefly from the decay of woody 

 fibre. All its forms are thence derived. It is from woody 

 fibre, by the absorption of oxygen, by the access of air and 

 moisture, that ulmic acid is first formed, and from this, by 

 absorption of another portion of oxygen proceeds humic 

 acid, and thus also, from this last again comes geic acid, and 

 thence crenic, which by still a further change becomes apo- 

 crenic acid. All these transformations are continually occur- 

 ring in soil. These occur not without the production of car- 

 bonic acid, water and ammonia. 



