408 Foreign and Miscellaneous Intelligence. 



burning like tallow ; having the consistence of tallow, and being of 

 the same nature as the butter of cocoa. The powdered grain treated 

 with water yields a small portion of this butter in a very pure and 

 fresh state. The quantity obtained from the original quantity of 

 seed was one ounce and a half. 



After all these operations the starch was separated by washing in 

 water; its quantity amounted to 32^ oz., or rather more than half 

 the weight of the dried seeds. When the recent seeds were worked 

 with for starch, I Ib. always yielded about 6 oz. of starch, and by 

 drying lost about 6 oz. of water. 



Besides these substances the following were also obtained ; -. 

 lignine above 5 oz. ; gum 2J oz. ; tannin 200 grs., nearly ; brown 

 resin 200 grs. ; green resin 144 grs., and a little vegetable albumen. 



M. Arequin then describes processes for obtaining gallic acid 

 from the mango seed, either with or without the use of alcohol, and 

 for the preparation of ink with this substance instead of galls. If 

 obtained in abundance, the seeds may be very useful for these and 

 analogous purposes *. 



17. ON LACTIC ACID. 



Berzelius has exerted his talents in the explication and clearance of 

 the doubts which have existed relative to the existence of lactic acid, 

 independent of the acetic acid. Gmelin, on distilling fluids contain- 

 ing lactic acid, obtained a product which feebly reddened litmus 

 paper, and which, saturated by baryta and the solution evaporated, gave 

 a white pellicle, which, when touched with sulphuric acid, evolved the 

 odour of acetic acid. 



Berzelius repeated the experiment, and obtained the same result, 

 but the acid odour never occurred unless muriatic acid was present in 

 the results of the distillation. When pure lactic acid with water was 

 distilled and the product evaporated, it reddened litmus paper, because 

 a little of the acid had been carried over with the vapours, but 

 tartaric acid was found to pass over in the same manner. In fact, it 

 is extremely difficult to prevent a little of the contents of the retorts, 

 in the finely divided state assumed, from passing over : but when the 

 product of lactic acid was distilled a second time, not a trace of acid 

 passed over. If acetic acid had been present it would have distilled. 



The question then arose whether lactic acid was a compound of 

 acetic acid and an animal matter analogous to the sulpho-yinates. 

 All attempts to prove this in the affirmative failed. Lactic acid was 

 heated up to the point at which extractive matter would become 

 brown, and then a current of ammonia passed over it, but no acetate 

 of ammonia passed forward in vapour, though that must have occurred 

 if acetic acid had been present. 



The following are the methods adopted by Berzelius to obtain pure 

 lactic acid. The acid alcoholic extract obtained from the liquids of 



* Journ, de Pharm., 1831, p,421. 



