Chemists

It is 52 years since 74 U. S. chemists journeyed into Pennsylvania to do reverence at the grave of Joseph Priestley, discoverer of oxygen, and to found there the American Chemical Society. Next week chemists from the world over will join their U. S. hosts at the Priestley grave, then go to Philadelphia for a Golden Jubilee convention of the Society in the engineering halls of the University of Pennsylvania.

Already, last week, the chemistry world was astir with impending events. Delegations from nine European countries, from Japan and South America, poured in. Leading his French colleagues was Chemist Paul Sabatier, Nobel prizeman in 1912, dean of the science faculty at Toulouse University. The senior chemists of many another famed university were expected.

The keynote of the conference was to be "the synthetic age," when man will not have to go beyond the chemical laboratory for his material needs, compounding them of the main life-supporting chemical elements. Advance apostles of this curious era had been propounding their visions at the Williamstown Institute of Politics, where President James F. Norris of the Society warned sentimentalists that, along with all other human activities, wars were going to be conducted with increased laboratory efficiency, employing poison gases and other destructive chemicals. Other speakers--not without opposition--discounted humanity's programs for conserving natural resources such as coal and oil, promising that chemists would provide substitutes if and when needed.

Priestley. The ceremony to be performed in Chemist Priestley's memory at Northumberland, Pa., at the "shrine of American chemistry," was to include an address by Dr. Charles A. Browne, chief of the U. S. Bureau of Chemistry, on Priestley's life and work. Dr. Browne would tell of a somewhat indigent, stammering, nonconformist minister, born in Yorkshire in 1733, shifting about England from one small parish to another, teaching school besides preaching, and performing experiments of "natural philosophy" in makeshift laboratories. Extremely versatile, never idle, he learned all that his contemporaries knew about electricity and wrote a history of that mysterious force. By hit-or-miss methods he obtained in his retorts "marine acid air" (hydrochloric acid gas), "vitriolic acid air" (sulphur dioxide), "fluor acid air" (silicon fluoride), "alkaline air" (gaseous ammonia). One day, he tried passing electric sparks through his "alkaline air" and found that it decomposed into nitro gen and hydrogen. Then, "having a notion" that ammonia and hydrochloric acid gas, mixed, might produce a "neutral air," he obtained some of the first pure crystals of sal ammoniac oy one more chance experiment.

Priestley did not know what he had made when he heated red oxide of mercury with a burning glass and collected the atmosphere caused by the process. He labored under an old notion that combustible substances had a constituent, "phlogiston," which departed from them when they burned (as soot, for example). Thus, when he found that a candle burned more brightly, and mice thrived, in the atmosphere created with his container of heated mercuric oxide, he thought this atmosphere was "dephlogisticated air." Fortunately, while touring Europe with a patron, he met the Frenchman, Lavoisier, and told him of his experiment. Lavoisier later worked out the modern theory that combustion ("fire") consists in the union of oxygen with another element, usually carbon--a discovery nearly as important as Newton's detection of gravity through the fall of an apple.

Besides Lavoisier, Priestley knew Volta (the Italian electrical pioneer), James Watt, Erasmus Darwin. Benjamin Franklin. He followed his sons to the U. S. in 1794, died at Northumberland in 1804.