In the following year he discovered rhodium; and at about the same time Smithson Tennant added two more to the list - iridium and osmium; the former was so named from the changing tints of its oxides (ipcs, rainbow), and the latter from the odour of its oxide (ovµA, smell).
Of great importance is the chemical identity of the diamond, graphite and charcoal, a fact demonstrated in part by Lavoisier in 1773, Smithson Tennant in 1796, and by Sir George Steuart-Mackenzie (1780-1848), who showed that equal weights.
It was first obtained in 1803 by Smithson Tennant (Phil.
SMITHSON TENNANT (1761-1815), English chemist, was born at Selby, Yorkshire, on the 30th of November 1761.
Experiments on the combustion of diamond were made by Smithson Tennant (1797) and Sir Humphry Davy (1816), with the object of proving that it is pure carbon; they showed that burnt in oxygen it yields exactly the same amount of carbon dioxide as that produced by burning the same weight of carbon.