'176 M. Ciiventou on Bromide of Ethyle. 



aqueous solution in pearly laminae, and from a less concentrated 

 solution in large glassy crystals. Its solution can be boiled 

 without change, but its salts are decomposed by this process. 



When the silver-salt was treated in this way, it was decom- 

 posed with formation of iodide of silver. The mother-liquor 

 from this yielded a substance which crystallized in fine needles, 

 was strongly acid, and evaporated without residue when heated 

 on platinum-foil. The analysis of this compound proved that 

 this was a substance having the same composition as lactic acid ; 

 but the investigation of the salts showed that it differed from 

 this acid. It is still under investigation. 



Beilstein also endeavoured, but without success, to form a 

 bromolactic acid with a view to effecting its conversion into gly- 

 ceric acid, by a reaction analogous to that by which chloropro- 

 pionic acid is converted into lactic acid. 



Caventou* has investigated some of the bromine substitution 

 products of bromide of ethyle. Bromide of ethyle was enclosed 

 in a sealed tube with excess of bromine and heated to about 170°. 

 By repeated fractional distillations of the product, two distinct 

 compounds were obtained: one, boiling at 110° to 112°, is mo- 

 nobrominated bromide of ethyle (G 2 H 4 Br) Br, and is isomeric 

 with bromide of ethylene; the other, boiling at 187°, is 

 (€ 2 H 3 Br 2 ) Br, and is not merely isomeric, but is identical 

 in properties with Wurtz's brominated bromide of ethylene, 

 (O 2 H 3 Br) Br 2 . There is another compound of the formula 

 € 2 H 4 Br 2 , bromide of ethylidene, obtained by the action of ter- 

 bromide of phosphorus on aldehyde. Unlike, however, its iso- 

 mers, bromide of ethylene and the body which Caventou has 

 described above, it cannot be distilled without undergoing de- 

 composition. 



Caventou found that brominated bromide of ethyle is decom- 

 posed when heated with acetate of potassium for two days to 

 140°, forming bromide of potassium and acetate of glycol — an 

 instance of the transformation of alcohol into a glycol compound. 



Zwenger and Dronkef have discovered in the blossoms of the 

 Acacia a new glucoside. It is prepared by treating the evapo- 

 rated aqueous extract of the blossoms with alcohol; the new 

 body, which they call Robinine, separates out from the concen- 

 trated alcoholic solution in crystals, which are pressed, dissolved 

 in boiling water, and treated with neutral acetate of lead to 

 remove foreign substances. The solution is then freed from lead 

 by treatment with sulphuretted hydrogen ; and, on the cooling 



* Liebig's Annalen, December 1861. 



t Liebig's Annalen (Supplement), December 1861. 



