238 EIGHTEENTH CENTURY. FT. in 



tion, and from this time chemistry advanced very rapidly. 

 Lavoisier invented an entirely new set of terms instead 

 of the old names of the alchemists, and though his 

 terms have been greatly altered by later discoveries, still 

 many of them will always be used. He repeated with a 

 better apparatus Cavendish's experiment of turning hydrogen 

 and oxygen into water, and he gave hydrogen its name from 

 v$up, water, and yevvaw, I produce. Lastly, he published 

 his 'Elements of Chemistry,' in which he gave a clear 

 explanation of the different chemical changes, and how 

 students could work them out for themselves. 



Lavoisier was now at the height of his fame, full of his 

 new theory, and prepared to devote the rest of his life to 

 making chemistry a grand science ; but a very sad fate was 

 awaiting him. In 1793 the great French Revolution broke 

 out in Paris. Lavoisier was a farmer-general, that is a kind 

 of collector of taxes, and all the farmers-general were hated 

 by the people ; so he knew that he should most likely lose 

 all his fortune, and was prepared to work for his living ; but 

 he had not expected the blow which fell upon him. All the 

 farmers -general were condemned to death, and though a 

 physician named Halle, who deserves always to be remem- 

 bered for this act, pleaded that Lavoisier's life should be 

 spared till he had completed his experiments, the ignorant 

 and brutal Government replied, * We do not need learned 

 men,' and on May 18, 1794, at the age of fifty-one, Lavoisier 

 was guillotined. 



After his death the French School of Chemistry, took the 

 lead for many years, until new discoveries in England, which 

 we shall mention by and by, made another great advance. 

 When you are able to read larger works upon the history of 

 chemistry you will find how very interesting the period was 

 of which we have been speaking. I have only been able to 



