23t Intelligence and Miscellaneous Articles. 



and has been examined since, principally by Braconnot and Berze- 

 lius: the former obtained an acid from rice and beet-root, which he 

 supposed to be peculiar, and gave it the name of nanceic acid, which 

 has been since found to be identical with lactic acid. 



Bouillon-Lagrange and L. Gmelin having suggested that lactic 

 acid was merely impure acetic acid, it appeared probable to Berze- 

 lius that it might be a compound acid, analogous to the sulphovinic : 

 he left the subject, however, in a state of uncertainty, admitting that 

 the lactates in a pure state are unknown. 



MM. J. Gay-Lussac and J. Pelouze exposed a considerable 

 quantity of beet-root juice to fermentation, in a stove the tempera- 

 ture of which was constantly between 77° and 81° Fahr. After 

 some days had elapsed, the tumultuous motion, known by the name 

 of the viscous fermentation, took place throughout the mass: hy- 

 drogen gas, mixed with carburetted hydrogen gas, was abundantly 

 disengaged. In about two months the fermentation ceases ; the 

 liquor becomes fluid again, and it is then to be evaporated to the 

 consistence of a syrup. Crystals of mannite are then diffused 

 through the liquor, and these, when washed with cold water and 

 pressed, are extremely pure : the mass contains, besides, a sugar 

 which had all the properties of grape sugar. In the fermentation 

 of beet-root juice, it appears that the cane sugar is first converted 

 into grape sugar and then into mannite ; for when the fermentation 

 is long continued, mannite only is obtained without grape sugar. 



The product of evaporation is to be treated with alcohol, which 

 dissolves the lactic acid, and precipitates some matters, which were 

 not examined : the alcoholic extract is treated with water, which 

 leaves another deposit. The solution is afterwards saturated with 

 carbonate of zinc, which occasions a more abundant precipitation 

 than the others. After concentration, the lactate of zinc crystal- 

 lizes : it is then to be dissolved in water and heated with animal 

 charcoal purified by muriatic acid. The solution is to be filtered 

 while boiling, and on cooling, perfectly colourless lactate of zinc cry- 

 stallizes : the crystals are to be washed with boiling alcohol, in which 

 they are insoluble. By treating them successively with barytes and 

 sulphuric acid, lactic acid is separated, which is to be concentrated 

 in vacuo \ by agitation with sulphuric aether, traces of flaky matter 

 are separated. 



Lactic acid thus obtained is quite colourless: if it should not be 

 so, which is the case when the last crystallizations of the lactate of 

 zinc have beenoperated upon, it is to be converted into lactateof lime, 

 which is to be boiled with water and purified animal charcoal. The 

 crystallized salt obtained is afterwards treated with boiling alcohol, 

 which dissolves it ; it is then to be redissolved in water and decom- 

 posed by oxalic acid. Thus prepared, it is always white and pure. 

 A large quantity of milk, suffered to ferment long, and treated in the 

 same manner, yielded an acid and salts which perfectly resembled 

 the preceding and its compounds. 



M. Corriol has lately discovered that a watery infusion of nux 

 vomica, after having fermented for some days, deposits lactate of 



