distinctly and faithfully noted in my various publications on the
subject, I by degrees contrived a convenient apparatus for the
purpose, but of the cheapest kind.

"When I began these experiments I knew very little of _chemistry_,
and had, in a manner, no idea on the subject before I attended a
course of chemical lectures, delivered in the Academy at
Warrington, by Dr. Turner of Liverpool. But I have often thought
that, upon the whole, this circumstance was no disadvantage to me;
as, in this situation, I was led to devise an apparatus and
processes of my own, adapted to my peculiar views; whereas, if I
had been previously accustomed to the usual chemical processes, I
should not have so easily thought of any other, and without new
modes of operation, I should hardly have discovered anything
materially new." [3]

The first outcome of Priestley's chemical work, published in 1772, was
of a very practical character. He discovered the way of impregnating
water with an excess of "fixed air," or carbonic acid, and thereby
producing what we now know as "soda water"--a service to naturally, and
still more to artificially, thirsty souls, which those whose parched
throats and hot heads are cooled by morning draughts of that beverage,
cannot too gratefully acknowledge. In the same year, Priestley
communicated the extensive series of observations which his industry
and ingenuity had accumulated, in the course of four years, to the
Royal Society, under the title of "Observations on Different Kinds of
Air"--a memoir which was justly regarded of so much merit and
importance, that the Society at once conferred upon the author the
highest distinction in their power, by awarding him the Copley Medal.