Bi-Malate of Lime in the Berries of the Sumach. 61 
This would give in 10 grains of the salt 1.28, differing by 
three hundredths of a grain from my determination. 
6. With the view of repeating some of the experiments of 
Lassaigne upon the acids produced by the destructive distil- 
lation of malic acid, I introduced several grains of the bi- 
malate into a glass tube, about one third of an inch in diame- 
ter and ten inches long. One end of the tube being herme- 
tically 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 colour collected on the surface of 
the tube. The liquid being removed from the tube was evapo- 
rated gently, and then suffered to cool. Numerous scaly 
crystals formed, resembling the flat figures which snow some- 
times assumes. These crystals were intensely acid, and so- 
luble in alcohol and in water. Heated in a test tube, they 
were partially decomposed, and needle shaped crystals sub- 
limed, 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 solu- 
tion of this pyromalic 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 substances agreed in 
properties with the pyromalic acids described by Lassaigne, 
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 properties extensively. Little is yet known 
concerning it and I am at present preparing to give it a more 
complete examination. 
The attention of the French and German chemists having 
lately been much directed to the constitution of the vegetable 
acids, various improved methods of obtaining the malic acid 
in a pure form, have been devised and published. In all 
