298 Bi-Malate of Lime in the Berries of the Sumach. 



entirely expelled. The lime remaining weighed 1.25 grains. This 

 result accords very closely with the composition of bi-malate, as de- 

 termined by Braconnot.* According to that chemist, as quoted by 

 Thomson, the constituents of the bi-malate are 



2 atoms malic acid, _ _ _ - - 17.00 



1 " lime, 3.5 



6 " water, 6.75 



27.25 

 This would give in 10 grains of the salt 1.2S, differing by three hun- 

 dredths of a grain from my determination. 



6. With the view of repeating some of the experiments of Las- 

 saigne upon the acids produced by the destructive distillation of ma- 

 lic acid, I introduced several grains of the bi-malate into a glass tube, 

 about one third of an inch in diameter and ten inches long. One end 

 of the tube being hermetically closed and the salt all collected in that 

 extremity, the tube was bent at two points, in a zigzag form. The 

 closed end was then held in the flame of a spirit lamp, to expel and 

 decompose the acid. In the angle of the tube remote from the 

 flame, an acid liquid mingled with empyreumatic tar collected, and 

 near the flame, adjacent to the salt, needle formed crystals of an 

 amber color collected on the surface of the tube. The liquid being 

 removed from the tube was evaporated gently, and then suffered to 

 cool. Numerous scaly crystals formed, resembling the flat figures 

 which snow sometimes assumes. These crystals were intensely acid, 

 and soluble in alcohol and in water. Heated in a test tube, they 

 were partially decomposed, and needle shaped crystals sublimed, 

 resembling those deposited near the closed end of the tube in the 

 first operation. Thrown upon burning charcoal, they exhaled a 

 white smoke, of a suffocating odor. A solution of this pyro-malic 

 acid in water, added to a solution of lead, produced a precipitate, at 

 first flocculent, but afterwards becoming gelatinous. The sublimate 

 was much less soluble than the acid just described. These substan- 

 ces agreed in properties with the pyromahc acids described by Las- 

 saigne, and thus another proof was furnished of the true nature of the 

 acid existing in the salt of the sumach. As but a small quantity of 

 the sublimate was procured, I was prevented from examining its prop- 

 erties extensively. Little is yet known concerning it and I am at 

 present preparing to give it a more complete examination. 



* Vide Thomson's Inorganic Chemistry, Vol. II. 



