4,04 Mr. Henry’s Experiments on 
mined by deflagrating it with oxygen, the combustion was in- 
complete, because a sufficiency of oxygen was not employed; 
and Dr. Austin himself was aware that, in each of them, “ a 
“ small quantity of heavy inflammable air might escape unal- 
“ tered.” It is observable, also, that the product of carbonic 
acid, from the electrified gas, increased in proportion as the 
combustion was more perfect. We may infer, therefore, that 
if it had been complete, there would have been no deficiency 
of this acid gas, and consequently no indication of a decom- 
position of charcoal. A strong objection, however, is appli- 
cable to these, as well as to most of Dr. Austin's experiments, 
that the residues were not examined with sufficient attention. 
In one instance we are told, that the remaining gas was inflam-i 
mable, and in another, that it supported combustion like vital 
air. I need hardly remark, that a satisfactory analysis cannot 
be attained of any substance, without the most scrupulous re- 
gard not only to the qualities, but to the precise quantities of 
the products of our operations. 
To the 8th and 9th experiments, the objection may be urged 
with additional weight, which has been brought against the 
preceding ones, that the quantity of oxygen, instead of being 
duly increased in the combustion of the electrified gas, was, 
on the contrary, diminished. Thus, in the 8th experiment, 
2,83 measures of carbonated hydrogen were inflamed with 4,38 
measures of oxygenous gas ; but in the 9th, though the 2,83 mea- 
sures were dilated to 5,1 6, and had therefore received a consi- 
derable addition of combustible matter, the oxygen employed 
was only 4,09. To the rest of Dr. Austin’s experiments either 
one or both of the above objections are applicable. 
The first and most important step, therefore, in the repetition 
