Geoscience Reference
In-Depth Information
both laboratorial and that invented by himself. It was a trait, or
perhaps self-training, that was to stand him in good stead for his
later career path. At school he was popular, and earned the nickname
'The Professor' for his scientific tinkerings. In 1876 after a short period
recovering in the south of France from a serious illness, he entered
Trinity College Dublin, where he remained for the rest of his life. He
followed courses in classics and modern literature but later concen-
trated on engineering, gaining the degree of Bachelor of Engineering
in 1882.
John Joly spent all of his academic and professional life working
in Trinity College, during which time he wrote 269 scientific papers
and several topic. Initially he was employed to teach and to assist the
Professor of Civil Engineering, which he did from 1882 until 1891. As
part of this research, apparatus had to be invented and built by Joly
himself. Among his first pieces were a new photometer and a hydro-
static balance. He also developed an interest in mineralogy, and began
to accumulate a large collection of some very fine Irish, Continental
and American mineral specimens. He invented the steam calorimeter
for measuring the specific heat of minerals, and this piece of equip-
ment later played an important role in the kinetic theory of gases.
In 1891, Joly was appointed assistant to George Francis Fitzgerald
(Professor of Natural and Experimental Philosophy). During the
following six years he invented and developed a mercury-glycerine
barometer and an electrolyte ampere-meter, and published on the
specific heat of gases. Joly's work was considered very important by
his contemporaries and he was elected a Fellowof the Royal Society (of
London) in 1892. This body was, and remains, the premier scientific
organisation in the United Kingdom. If one examines his publications
for 1895 and 1896 one can immediately appreciate the broad range of
interests of the man: he wrote on the ascent of sap, on heat, and on
gravitation, and he also published on his newmethod of colour photo-
graphy. All in all, he had an incisive mind and was able to deal with
complex scientific issues quickly, and, perhapsmore importantly, was
dexterous enough to devise and manufacture much of his own
