AMMONIA NITEATE WITH AMMONIA. 
363 
15°-5 calculated by means of its approximate coefficient of dilatation, which was deter- 
mined by other observations.) 
By taking the numbersexpressing the specific gravity and composition of Nos. 1 & 6, 
it is easy to compute the specific gravity of the excess of the ammonia in No. 1 over 
that in No. 6, on the assumption that the latter liquid undergoes no change in density by 
uniting with more ammonia. On making the further assumption that all the ammonia 
condensed by the nitrate has the same density, the specific gravity of the nitrate in the 
liquid can also be calculated ; or this can be found directly for the excess of the nitrate 
in No. 6 over that in No. 1 in union with the same weight of ammonia, in the same 
way as that for the ammonia was calculated. On then calculating from the weights of 
the two substances, and the specific gravities thus found for them, the specific gravities 
of the liquids the composition of which is given in the preceding Table, the assump- 
tion that the densities of the two substances are constant is found to be correct, in 
so far, that is, as the results are concerned. The calculated specific gravity of the 
ammonia is 671, and that of the nitrate 1524-5. The specific gravities of the liquids 
calculated from these numbers are placed in the following Table by the side of those 
found by experiment, and their almost entire identity within the limits of experimental 
error thus rendered apparent : — 
No. 
Calculated. 
Pound. 
1 
. 1072-5 
1072-5 . 
2 
. 1122-0 
1119-95 
3 
. 1126-3 
1126-05 
4 
. 1156-1 
1155-9 
5 
. 1167-35 
1167-05 
6 
. 1191-45 
1191-65 
7 
. 1198-55 
1199-0 
Except in the case of No. 2 the differences between the two series of numbers are 
quite within the limits of experimental error, and in that case some unobserved error 
no doubt must have been made in the determination. 
The calculated specific gravity of the ammonia in these liquids (671) is greater than 
that found for ammonia liquefied by pressure by Andreeff* (615-5 at 15 0, 5) or by 
JoLLYf (623 - 4 at 0 C ). GriffinJ has calculated the specific gravity of ammonia liquefied 
by water to be constantly 708, on the usual assumption that the density of the water is 
constant, a number not far from that found by Earaday§ (731) for ammonia liquefied 
by pressure. The calculated specific gravity of the nitrate in the liquid (1524-5) is 
much less than the number (1740) found for the solid nitrate by Karsten [|, that by 
Kopp^[ (1707), or that by Playfair and Joule*'*' (1635); it is also much less than the 
* Ann. Chim. Phys. [3] lvi. p. 317. t Ann. Ch. Pharra. cxvii. p. 181. 
J Mem. Chem. Soe. iii. p. 155. § Phil. Trans. (1845) p. 169. 
|| Per. Abhandl. (1840) p. 95. *[[ Ann. Ch. Pharm. xxxvi. (1840) p. 1. 
** Mem. Chem. Soc. ii. p. 436. 
