Now Lavoisier[57] allows about 51 of dry acid to 100 grains of nitre, and Wenzel 52.
From Berthollet’s[58] experiments, 100 grains of nitre, in their decomposition by heat, give out nearly 49 grains of gas.[59]
Hence it appears that the aëriform acid, that is, the true acid of my table, contains rather less water than the acid supposed to exist in nitre.
DIVISION II.
EXPERIMENTS and OBSERVATIONS on the composition of AMMONIAC and on its combinations with WATER and NITRIC ACID.
I. Analysis of AMMONIAC or VOLATILE ALKALI.
The formation and decomposition of volatile alkali in many processes, was observed by Priestley, Scheele, Bergman, Kirwan, and Higgins; but to Berthollet we owe the discovery of its constituent parts, and their proportions to each other. These proportions this excellent philosopher deduced from an experiment on the decomposition of aëriform ammoniac by the electric spark:[60] a process in which no apparent source of error exists.
Since, however, his estimations have been made, the proportions of oxygene and hydrogene in water have been more accurately determined. This circumstance, as well as the conviction of the impossibility of too minutely scrutinizing facts, fundamental to a great mass of reasoning, induced me to make the following experiments.
A porcelain tube was provided, open at both ends, and well glazed inside and outside, its diameter being about,5 inches. To one end of this, a glass tube was affixed, curved for the purpose of communicating with the water apparatus. With the other end a glass retort was accurately connected, containing a mixture of perfectly caustic slacked lime, and muriate of ammoniac.
The water in the apparatus for receiving the gases had been previously boiled, to expel the air it might contain, and during the experiment was yet warm.