Dr. Thomson on Oxalic 'Acid. 71 
of this salt contained in solutions of different specific gravities, 
I have thought it worth while to construct the following 
table : 
Weight of oxalate 
of ammonia in 100 
parts of the solu- 
tion. 
Specific gra- 
vity of the so- 
Weight of oxalate 
of ammonia in ioo 
Specific gra- 
vity of the so- 
lutiou at 6o°. 
parts of the solu- 
tion. . - 
lution at 6o°. 
4-32 
1.0186 
r 1.5 
I.OO75 
4- 
IOI79 
1. 
I.OO54 
35 
1.0160 
0.5 
I.OO30 
3 ■ 
I.OI42 
0.4 
I.OO24 
2.5 
1.0120 
0.3 
l.OOlS 
2. 
rr 
O: 
0 
O 
6 
0.2 
1.0012 
.. 
0.1 
1 .0006 
8. To determine the composition of these salts, I took seven 
different portions of a diluted oxalic acid solution, each weigh- 
ing 100 grains, and containing 7 grains of real oxalic acid. 
To each of these portions I added respectively potash, soda, 
ammonia, barytes water, strontian water, and lime water, till 
it ceased to produce any change. The liquid was then evapo- 
rated to dryness, and the residue, after being well dried on the 
steam bath, was weighed. Each of these salts contained 7 
grains of acid ; the additional weight I ascribed to the base. 
Hence I had the follpwing table, which exhibits the weight of 
each salt obtained, and its composition deduced from that 
weight. 
