SKETCH OF LAVOISIER. 551 



liim into association with farmer-general Paulze, whose daughter 

 he married, and who went with him to the scaffold. In 177G Tur- 

 got made him inspector-general of powder and saltpeter. In this 

 capacity he made great improvements in the manufacture, so that, 

 while he put a stop to forced official searches for saltpeter in the 

 cellars of private houses, he quadrupled the product of the salt, 

 and so increased the explosive force of gunpowder that the 

 French brand became as much superior to the English as it had 

 been inferior. 



Lavoisier's great work consisted in the discovery of the true 

 functions of oxygen and the nature of combustion ; the determi- 

 nation of the relations of the solid, liquid, and gaseous states of 

 matter ; and in many other observations that embodied the germs 

 of what have become since the leading principles of chemical sci- 

 ence. Oxygen was detected at about the same time by Priestley, 

 Scheele, and Lavoisier ; but the phlogistic theory of combustion 

 possessed the minds of chemists, and, although Eck de Suchbach 

 and Jean Rey had already dimly discerned the truth, no one had 

 paid any attention to their discoveries, and Lavoisier was work- 

 ing on what was to him, and substantially to the world, virgin 

 ground. " Fixed air " and " combustible air " had been speculated 

 upon, and " the air that is left after combustion " had attracted at- 

 tention. But the phenomena of this kind, inconsistent as they 

 were with the phlogistic theory, had not been sufficient to over- 

 throw it. The first germ of Lavoisier's theory on these matters 

 was embodied in a sealed packet which he deposited with the 

 Academy in 1770. Recognizing that the calcination of metals 

 could not take place without the access of air, and that the freer 

 the access the more rapid the calcination, he " began to suspect," 

 as he expresses himself, that some elastic fluid contained in the 

 air was susceptible, under many circumstances, of fixing itself and 

 combining with metals, and that to the addition of that substance 

 were due calcination and the increase in weight of metals con- 

 verted into calxes. From this thought came, after much groping 

 with erroneous conclusions, the idea that air is a compound con- 

 taining a vital part and another part, and that it is the vital part 

 that is absorbed. The behavior of charcoal when burning in oxy- 

 gen pointed to the nature of that substance and to the true theory 

 of combustion. This new vital substance, which, uniting with 

 metals, formed calxes, and with other substances generated acids, 

 he called oxygen or the acid-producer ; the air that was left after 

 combustion was azote, or lifeless. The inflammable air which, 

 combining with oxygen, was found to form water, was called hydro- 

 gen. Upon these facts, and with a few other names of known sub- 

 stances, Lavoisier constructed the system of chemical nomenclature 

 which, after having undergone many modifications to conform to 



