Dr . Henry's Experiments on Ammonia. 44,7 
reflection, as well as the candid and judicious criticisms of 
various writers,* have influenced me to doubt of the accuracy 
of a few of the conclusions drawn from my former inquiries. •f* 
The knowledge of this class of bodies has, also, been so ma- 
terially advanced during the last twelve years, that the exa- 
mination of their properties may now be undertaken, with 
much greater confidence and success than formerly. It is to 
be lamented, indeed, that experimentalists do not oftener re- 
trace their labours, with the combined advantages of acquired 
skill, and of a more improved state of the science which they 
investigate. 
The gases, submitted by Mr. Dalton and myself to the 
action of long continued electrization, were carburetted hy- 
drogen from pit-coal of the specific gravity of about (350 (air 
being 1000) olefiant gas, and carbonic oxide. Each gas was 
used in as pure a state as possible ; muriate of lime being first 
introduced into the same tubes in which the gases were elec- 
trified, and being withdrawn when it had exerted its full 
action. Platina wires were used to convey the electric dis- 
charges. 
When the electrization of carburetted hydrogen or olefiant 
gases was continued sufficiently long, they were each found 
to expand, notwithstanding their extreme dryness. No car- 
bonic acid could be discovered in the electrified gas by the 
nicest tests. When fired with oxygen, it gave less carbonic- 
* See Berthollet’s Chemical Statics, Eng. trans.Vol.il. p. 454- i Murray's 
E lements of Chemistry, Vol. II. Note G ; a letter from an anonymous correspondent 
in Nicholson’s Journal, 8vo. II. 185 ; and Ai kin’s Dictionary of Chemistry, I. 251. 
f “ Experiments on Carbonated Hydrogen Gas, with a View to determine whether 
Carbon be a simple or a compound body.” Phil. Trans. Vol. LXXVII. 
2 M a 
