SIR HUMPHREY DAVY. 147 



with zeal to his professional studies, had read 

 Locke, and Bollin, and Gibbon, and Shakspeare, 

 and at twenty had been appointed to take charge 

 of the Pneumatic Institution at Clifton, established 

 by Dr. Beddoes. It had been founded to give an 

 opportunity of trying the medicinal effects of vari- 

 ous gases, and was supported by liberal men of 

 science. So distressed was his old friend, Mr. 

 Tonkin, that he should give up the idea of being a 

 surgeon in Penzance, that he revoked a legacy he 

 had made him in his will ! 



Davy's life was now an extremely busy one. He 

 published, when he was twenty-one, his " Essays 

 on Heat and Light," beginning his work, like Sir 

 Isaac Newton, when but a youth. He discovered 

 silica in the epidermis of the stems of weeds, corn, 

 and grasses. He found the intoxicating effects of 

 breathing nitrous oxide, April 9, 1799, and his 

 experiments on this subject were published the 

 following year. He spent ten months of incessant 

 labor in them, often endangering and once nearly 

 losing his life from breathing carburetted hydro- 

 gen. He made experiments on galvanic electric- 

 ity, increasing the powers of the Galvanic Pile 

 of Yolta. He also planned and partly wrote an 

 epic poem on the deliverance of the Israelites from. 

 Egypt. 



Worn with overwork, he returned to see his wid- 

 owed mother at Penzance. He had been absent a 

 year. How glad were all to greet the rising young 

 scientist ! Not least glad was Davy's water spaniel, 



