170 BIOGRAPHIES OF SCIENTIFIC MEN 



reward for six years' hard work. His discoveries he 

 described in his second Bakerian lecture before the 

 Royal Society. 



The decomposition of potash and soda, proving their 

 compound nature, led to the discovery of barium, stron- 

 tium, calcium, magnesium, and boron. Thus, by means 

 of the electric battery, Davy proved that the alkalis and 

 alkaline earths were compounds, and contained metals. 

 These discoveries were the foundation of Davy's fame, and 

 are, perhaps, "the greatest in chemistry." As Professor 

 T. E. Thorpe says : " It was a wonderful triumph, and all 

 London marvelled at the production from such common 

 and familiar substances of new, white, soft, easily-oxidized, 

 shining metals, which the eye of man had never seen 

 before ! " 



In 1812 Davy was knighted, and married a rich Scottish 

 lady, Mrs Apreece. The same year he resigned the 

 chair at the Royal Institution, and in 1813 travelled with 

 his wife on the Continent. 



From 1802 to 1812 his labours were intense, and his 

 discoveries were of the highest importance. 



In 1813 Michael Faraday became Davy's assistant, 

 and he helped the master in the work on the explosive 

 chloride of nitrogen. 



In 1815 (the year of the battle of Waterloo) Sir 

 Humphry Davy invented the miner's safety-lamp. For 

 this invention he was created a baronet in 1818 ; and the 



