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XVIII. New experimental researches on some of the leading doc- 
trines of caloric ; particularly on the relation between the 
elasticity , temperature, and latent heat of different vapours ; 
and on thermometric admeasurement and capacity. By Andrew 
Ure, M. D. Communicated by W. H. Wollaston, M. D. F. R. S. 
Read April 30, 1818. 
Glasgow , July 1817. 
1. On the elastic force of vapours, with new formulae to determine 
it at any temperature ; and a review of those given by Dalton 
and Biot. 
The phenomena attending the conversion of liquids into 
elastic fluids, were first accurately investigated by Dr. Black. 
He observed in the rising of vapour, and melting of ice, a 
beautiful system of relations, connecting and modifying the 
grandest operations of nature, while they were destined to 
afford new principles for the advancement of the arts. If it 
be the prerogative and characteristic of genius, to discover in 
the most familiar, or, as some would say, vulgar phenomena, 
that mystic chain of causation, which had eluded all other 
eyes, unquestionably, the doctrines of latent heat entitle their 
author to rank in the first class of philosophers. 
Dr. Black directed his attention principally to the establish- 
ment of the general laws, which he placed on an immoveable 
basis ; leaving to his pupils, the subordinate task of investi- 
gating their individual applications. Hence, the elastic forces 
of the vapours, arising from different bodies, at different 
temperatures, seem to have occupied him very little, if at alh 
