nd probably did much in determining his career. Fortunately
for him, and incidentally for the cause of science, he was able to
pursue laboratory investigations without being obliged to mingle with
his dreaded fellow-mortals, his every want being provided for by the
immense fortune inherited from his father and an uncle.

When a young man, as a pupil of Dr. Black, he had become imbued with the
enthusiasm of his teacher, continuing Black's investigations as to the
properties of carbonic-acid gas when free and in combination. One of his
first investigations was reported in 1766, when he communicated to
the Royal Society his experiments for ascertaining the properties of
carbonic-acid and hydrogen gas, in which he first showed the possibility
of weighing permanently elastic fluids, although Torricelli had before
this shown the relative weights of a column of air and a column of
mercury. Other important experiments were continued by Cavendish, and
in 1784 he announced his discovery of the composition of water, thus
robbing it of its time-honored position as an "element." But his
claim to priority in this discovery was at once disputed by his
fellow-countryman James Watt and by the Frenchman Lavoisier. Lavoisier's
claim was soon disallowed even by his own countrymen, but for many
years a bitter controversy was carried on by the partisans of Watt and
Cavendish. The two principals, however, seem never to have entered
into this controversy with anything like the same ardor as some of their
successors, as they remained on the best of terms.(1) It is certain, at
any rate, that Cavendish announced his discovery officially before Watt
claimed that the announcement had been previously made by him, "and,
whether right or wrong, the honor of scientific discoveries seems to be
accorded naturally to the man who first publishes a demonstration of his
discovery." Englishmen very generally admit the justness of Cavendish's
claim, although the French scientist Arago, after reviewing the evidence
carefully in 1833, decided in favor of Watt.

It appears that something like a year before Cavendish made known his
complete demonstration of the composition of water, Watt communicated
to the Royal Society a suggestion that water was composed of
"dephlogisticated air (oxygen) and phlogiston (hydrogen) deprived of
part of its latent heat." Cavendish knew of the suggestion, but in his
experiments refuted the idea that the hydrogen lost any of its late