CHEMISTRY OF THE PTOMAINES. 245 



deserve special mention at this place. He carried on the 

 putrefaction of very dilute solutions of the chloride of 

 choline in the presence of little or no oxygen in Hopi'E- 

 Seyler fermentation flasks. Sewer slime, because of its 

 strong fermentative properties, was used to induce the 

 putrefaction, and calcium carbonate was added to neu- 

 tralize any acidity that might develop) during the fermen- 

 tation. 



The fermentation, as shown by the evolution of gases, 

 lasted for about three months. The total quantity of gas 

 given off was about one litre from 1.17 grammes choline 

 chloride. The gases consisted almost entirely of carbouic 

 acid and marsh gas. No hydrogen was evolved. When 

 the fermentation ceased the flask was opened and several 

 cubic centimetres of the almost neutral clear liquid were 

 injected under the skin of a rabbit without producing the 

 least effect. 



This liquid distilled with alkali gave methylamine 

 and ammonia. What is remarkable about this experiment 

 was the total absence of the higher amines — as, for instance, 

 trimethylamine, which has been observed so many times as 

 a decomposition-product of choline. The abseuce of any 

 poisonous base, as neurine, was probably largely connected 

 with the absence of oxygen. 



Free choline ordinarily forms a strongly alkaline syrup 

 which combines readily with acids to form salts, most of 

 which are deliquescent. By oxidation it is converted into 

 betaine (see page 249), and on treatment with concentrated 

 nitric acid it gives rise to muscarine (see page 251). These 

 reactions can be represented by the equations : 



CH.OII C<Qjj 



CH, +0,= CH, +H,0. 



I I 



N(CH3)3.0H N(CH3)3.0H 



Choline. Betaine. 



