The composition of water was discovered about one hundred years ago.
Cavendish found hydrogen in 1776, and Priestly discovered oxygen in 1774,
August 1st, a date which some one says “may almost be accepted as the
birthday of modern chemistry.”
Is it not remarkable that four of the brightest “red letter days” in the
history of this science should be embraced within two decades, from 1754
to 1774? In 1754 Joseph Black discovered carbonic acid gas; in 1766 Dr.
Cavendish found hydrogen; in 1772 Dr. Rutherford discovered nitrogen, and
in 1774 Dr. Priestly found the King of the Elements, oxygen. Until then
mankind were ignorant of the existence of a substance which composes in
the aggregate one half the earth.