He was now at work apparently in his own little laboratory adjacent to his dwelling place. For more than a century this structure has remained practically as it was in the days of Priestley. In it he did remarkable things, in his judgment; thus refuting the general idea that after his arrival in America nothing of merit in the scientific direction was accomplished by him. The satisfactory results, mentioned to Lindsey, were embodied in a series of "Six Chemical Essays" which eventually found their way into the Transactions of the American Philosophical Society. It is a miscellany of observations. In it are recorded the results found on passing the "vapour of spirit of nitre" over iron turnings, over copper, over perfect charcoal, charcoal of bones, melted lead, tin and bismuth; and there appears a note to the effect that in Papin's digester "a solution of caustic alkali, aided by heat, made a liquor silicum with pounded flint glass." There is also given a description of a pyrophorus obtained from iron and sulphur. More interesting, however, was the account of the change of place in different kinds of air, "through several interposing substances," in which Priestley recognized distinctly for the first time, the phenomena of gaseous diffusion. There are also references to the absorption of air by water, and of course, as one

would expect from the Doctor, for it never failed, there is once more emphasized "certain facts pertaining to phlogiston." His friends were quite prepared for such statements. They thought of Joseph Priestley and involuntarily there arose the idea of phlogiston.

The little workshop or laboratory, in Northumberland, where these facts were gathered, will soon be removed to the Campus of Pennsylvania State College. It will be preserved with care and in it, it is hoped, will be gradually assembled everything to be found relating to the noble soul who once disclosed Nature's secrets in this simple primitive structure, which American chemists should ever cherish, and hold as a Mecca for all who would look back to the beginnings of chemical research in our beloved country.

How appropriate it would be could there be deposited in the little laboratory, the apparatus owned and used by Priestley, which at present constitutes and for many years past has formed an attractive collection in Dickinson College, (Pa.) There would be the burning lens, the reflecting telescope, the refracting telescope (probably one of the first achromatic telescopes made), the air-gun, the orrery, and flasks with heavy ground necks, and heavy curved tubes with ground stoppers—all brought (to Dickinson) through the

instrumentality of Thomas Cooper, "the greatest man in America in the powers of his mind and acquired information and that without a single exception" according to Thomas Jefferson.

And how the Library would add to the glory of the place, but, alas! it has been scattered far and wide, for in 1816, Thomas Dobson advertised the same for sale in a neatly printed pamphlet of 96 pages. In it were many scarce and valuable books. The appended prices ranged quite widely, reaching in one case the goodly sum of two hundred dollars!

And as future chemists visit this unique reminder of Dr. Priestley it should be remembered that on the piazza of the dwelling house there assembled August 1, 1874, a group of men who planned then and there for the organization of the present American Chemical Society.

The "Essays," previously mentioned, will be found intensely interesting but they are somewhat difficult to read because of their strange nomenclature. Here is Priestley's account of the method pursued by him to get nitrogen:

Pure phlogisticated air (nitrogen) may be procured in the easiest and surest manner by the use of iron only—To do this I fill phials with turnings of malleable iron,

and having filled them with water, pour it out, to admit the air of the atmosphere, and in six or seven hours it will be diminished ... what remains of the air in the phials will be the purest phlogisticated air (nitrogen).