of Edinburgh, Session 1884-85. 
183 
It is readily soluble ia alcohol and water, and less easily in ether. 
Its iron and lead salts are yellowish crystalline precipitates ; that of 
barium of straw yellow, and of silver white. They are all slightly 
soluble in water. The alkali and calcium salts, which are also light 
yellow, are readily soluble in water and in alcohol. A quantity of 
the silver salt was prepared by decomposing silver acetate with 
aqueous solution of the acid. The ensuing precipitate was 
analysed with the following result : — 
I. 
II. 
Mean. 
Theory for 
c i3 H i8 A gA nee ds 
Carbon, . 
21-20 
21-19 
21-20 
21-25 
Hydrogen, 
2-39 
2-59 
2-49 
2-45 
Silver, 
58-86 
58-86 
58-86 
58-85 
Oxygen, . 
17-55 
17-36 
17-45 
17-45 
100-00 
100-00 
100-00 
100-00 
This silver salt suffers partial decomposition, blackening when 
exposed to sunlight. The barium salt of this acid was also prepared 
by exactly neutralising its aqueous solution with barium carbonate. 
The solution was evaporated to dryness, and the substance obtained 
analysed. By carefully and slowly evaporating the aqueous 
solution of either the silver or the barium salt, the substance can be 
got in minute hard crystals. 
Carbon, . 
Found. 
27-02 
Theory for 
C 13 H 18 Ba 2 0 8 requires 
27-08 
Hydrogen, 
3-09 
3-13 
Barium, . 
47-60 
47-57 
Oxygen, . 
22-29 
22-22 
100-00 
100-00 
From the analyses of its salts the acid is evidently a new one, 
and tetrabasic, being represented by the formula C 9 H 18 (CQOH ) 4 • 
but no name has yet been given to it. 
The distillation of urushic acid with lime gives a small quantity 
of light hydrocarbon, which, however, appears to polymerise very 
easily during its purification by fractional distillation. The nature 
of this oil is being examined; but one of the lighter fractions 
analysed gave numbers which indicate a composition approaching 
that represented by C 14 H 24 , showing it to be probably one of the 
