362 NINETEENTH CENTURY, Yi. iir. 



CHAPTER XXXVI. 



SCIENCE OF THE NINETEENTH CENTURY (CONTINUED). 



Davy discovers that Nitrous Oxide produces Insensibility — Laughing- 

 gas — Safety-lamp, 1815 — Nicholson and Carlisle discover Decom- 

 position of Water, 1800 — Davy discovers the effect of Electricity 

 upon Chemical Affinity — Faraday's Discoveries in Electrolysis — 

 Indestructibility of Force — Various modes discovered of Decompos- 

 ing Substances — John Dalton, Chemist — Law of Definite Propor- 

 tions — Law of Multiple Proportions — Dalton's Atomic Theory — 

 The study of Organic Chemistry — Liebig the great Teacher in 

 Organic Chemistry. 



Sir Humpliry Davy, 1778-1829. — We saw in the last 

 chapter how Oersted, Davy, Ampbre, Faraday, and Seebeck, 

 by their various discoveries, showed the connection between 

 Electricity, Magnetism, and Heat. We must now learn how 

 the connection between electricity and chemical change was 

 also worked out. This was done by Sir Humphry Davy and 

 Faraday, who thus put England once more at the head of 

 chemical discovery, in which the French school of Lavoisier 

 had so long taken the lead. 



Sir Humphry Davy, whom we have mentioned before as 

 making experiments upon heat, was born in 1778, at Pen- 

 zance, in Cornwall, and died at Geneva in 1829. His mother 

 being a widow, he was apprenticed when quite young to 

 an apothecary, and there with wine glasses, old medicine 

 bottles, tobacco pipes, and a syringe, he made his first 

 chemical experiments. When he was scarcely twenty years 



