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 Society that he had executed other experiments which corroborated those outlined in his first two papers, adding
Had the publication of your Transactions been more frequent, I should with much pleasure have submitted to the Society a full account of these and other experiments which appear to me to prove, that metals are compound substances, and that water has not yet been decomposed by any process that we are acquainted with. Still, however, I would not be very positive, as the contrary is maintained by almost all the chemists of the age....
And thus he proceeds, ever doing interesting things, but blind to the patent results because he had phlogiston constantly before him. He looked everywhere for it, followed it blindly, and consequently overlooked the facts regarded as most significant by his opponents, which in the end led them to correct conclusions.
The experimental results in the second paper also admit of an interpretation quite the opposite of that deduced by Priestley. He confidently maintained that air was invariably generated from water, because he discovered it and liberated it from water which he was certain did not contain it in solution. He was conscientious in his inferences. Deeply did his friends deplore his
inability to see more than a single interpretation of his results!
The papers were read before the American Philosophical Society on the 19th of February, 1796. Their author as they appear in print, is the Rev. Dr. J. Priestley. It is doubtful whether he affixed this signature. More probable is it that the Secretary of the Society was responsible, and, because he thought of Priestley in the rôle of a Reverend gentleman rather than as a scientific investigator.
Here, perhaps, it may be mentioned that the first, the very first communication from Priestley's pen to the venerable Philosophical Society, was read in 1784. It was presented by a friend—a Mr. W. Vaughan, whose family in England were always the staunchest of Priestley's supporters. And it is not too much to assume that it was the same influence which one year later (1785) brought about Priestley's election to membership in the Society, for he was one of "28 new members" chosen in January of that year.
There are evidences of marked friendliness to Priestley all about the Hall of the Society, for example his profile in Plaster of Paris, "particularly valuable for the resemblance" to the Doctor, which was presented in 1791; a second "profile in black leather" given by Robert Patterson,