copper and zinc). This battery, although non-existent now, was the means of producing valuable discoveries in the hands of Gay-Lussac and Thénard.
Davy proved that oxygen was not the acidifying principle of acids, as stated by Lavoisier; and he led the way to the ultimate definition of an acid.
In 1803 Davy was elected F.R.S.; in 1807, Secretary of the Royal Society; and in 1820, its President. During these years a vast number of papers were published by him; and he published the following books: Elements of Agricultural Chemistry (1813); Elements of Chemical Philosophy; Salmonia, or Days of Fly-fishing; and Consolation in Travels, or the Last Days of a Philosopher (published in 1831, two years after his death). The last-named book contains some finely written theories on ethical and moral questions, with descriptions of Italian scenery.
In his book on Agricultural Chemistry, Davy says:—