isticated air, phlogisticated air, and so forth. In the very
first paper, the opening lines show this:

It is an essential part of the antiphlogistic theory, that in all
the cases of what I have called _phlogistication_ of _air_, there
is simply an absorption of the dephlogisticated air, or, as the
advocates of that theory term it, the oxygen contained in it,
leaving the _phlogisticated_ part, which they call _azote_, as it
originally existed in the atmosphere. Also, according to this
system, _azote_ is a simple substance, at least not hitherto
analyzed into any other.

No matter how deeply one venerates Priestley, or how great honor is
ascribed to him, the question continues why the simpler French view was
not adopted by this honest student. Further, as an ardent admirer one
asks why should Priestley pen the next sentence:

They, therefore, suppose that there is a determinate proportion
between the quantities of oxygen, and azote in every portion of
atmospherical air, and that all that has hitherto been done has
been to separate them from one another. This proportion they state
to be 27 parts of oxygen and 73 parts of azote, in 100 of
atmospherical air.

Priestley knew that there was a "determinate proportion." He was not,
however, influenced by quantitative data.

Sir Oliver Lodge said[4]--

Priestley's experiments were admirable, but his perception of
their theoretical relations was entirely inadequate and, as we
now think, quite erroneous.... In theory he had no instinct for
guessing right ... he may almost be said to have had a
predilection for the wrong end.

At present the French thought is so evident that it seems
incomprehensible that Priestley failed to grasp it, for he continues--

In every case of the diminution of atmospherical air in which this
is the result, there appears to me to be something emitted from
the substance, which the antiphlogistians suppose to act by simple
absorption, and therefore that it is more probable that there is
some substance, and the same that has been called _philogiston_,
or the _principle of inflammability_ ... emitted, and that this
phlogiston uniting with part of the dephlogisticated air forms
with it part of the phlogisticated air, which is found after the
process.

Subsequently (1798), he advised the Soci