Intelligence and Miscellaneous Articlesl 139 



't> 



cipitates the nitrate of lead, whilst the sesquichloride and pernitrate 

 of iron are only partially precipitated by the sulphuret of lead, — 

 Journal de Pharmacies October 1837. 



ON THE FERMENTATION OF SUGAR OF MILK. BY M. HESS. 



It has generally been admitted by chemists as an indisputable 

 fact, that sugar or milk is incapable of fermentation. Pallas endea- 

 voured, but in vain, in his collection of historical facts respecting 

 the people of Mogol, (St. Petersburgh, 1776, vol. i. p. 33), to con- 

 trovert this generally received opinion, by objecting that the people 

 of Asia prepared an intoxicating liquor from milk; although this 

 fact was known to many persons, and has often been quoted re- 

 specting milk, the idea has nevertheless remained, that sugar of 

 milk is not susceptible of the alcoholic fermentation, and it has 

 been proposed to expunge it from the list of sugars, and to give 

 the name of lactin. 



In order to elucidate this subject by some experiments, M. Hess 

 fermented cow's milk in wooden vessels ; the fermentation occurred 

 spontaneously and without any addition ; it is necessary only that 

 the vessels should be sufficiently deep and exposed to a sufficiently 

 high temperature ; it is of no consequence whether the milk be pre- 

 viously skimmed or not. The fermentation continues for a long 

 period ; it is accompanied with a disengagement of gas, perceptible 

 even by the ear. The gas collected was examined by solution of 

 potash, which absorbed it within y^ part, which could be nothing 

 but atmospheric air ; the fermented liquor was passed through a 

 flannel, to separate the ferment, and afterwards distilled. The 

 product of the distillation was acid ; it was saturated with carbonate 

 of lime, and several times redistilled, taking care to receive each 

 time only one-fourth of the liquid. The liquor thus obtained was 

 mixed with excess of dry carbonate of potash, which combined with 

 the water, and an alcoholic liquor floated on the saline one ; it was 

 separated by repeated distillations from the salts which it contained; 

 then, in order to have it pure, it was rectified from lime ; it always 

 possessed a peculiar odour. By analysing O'^S of this liquid there 

 were obtained 0*827 of carbonic acid, and 0*561 of water_, which 

 gives for 100 parts : 



Carbon 47"64 



Hydrogen 1 2*96 



Oxygen 39*4'0 



100* 



and as 4?7'64? of carbon indicate 90*46 of alcohol, which are equal to 



Carbon l-7'64 



Hydrogen 11*66 



Oxygen 31*16 



90-46 



there remain 13 of hydrogen, which indicate 1181 of water, from 

 which there results an excess of 2*27 in 100. As M. Hess performed 

 this analysis with care, and believed he was sufficiently guarded from 

 the usual source of error, that is, of hygrometric moisture, he pre- 



T2 



