Dr. Ure’s new experimental researches , &c, 333 
This subject was examined, however, with great ability, by 
two of his most distinguished friends. Professor Robison and 
Mr. Watt. The investigations of the former were published 
in the Encyclopaedia Britannica, article steam ; while we have 
still to regret our ignorance of those executed by the latter 
philosopher, with probably a more complete apparatus, and 
more extensive views. We are indebted to hirn, indeed, for 
some curious observation on the latent heat of steam, at 
different temperatures, which make us lament more, the want 
of those on the elastic forces themselves. 
Mr. Dalton, whose peculiar speculations on caloric and 
meteorology led him to study the formation and variable 
elasticity of vapour with great attention, has since then 
favoured the world with many excellent dissertations, and is 
now reckoned the first authority on the subject. Mr. Dalton’s 
experiments on the steam of water were carried no higher 
than its ordinary boiling point ; but from the observed pro- 
gression of its elastic force he investigated a formula, and 
calculated from it a table for the higher temperatures.* 
In the second number of the Journal Poly technique, M. 
Betancourt, an eminent Spanish engineer, long resident at 
Paris, published a set of experiments on the same subject, the 
results of which differ from those of Mr. Dalton in many 
particulars, but most remarkably in the higher part of the 
scale. 
Having had my mind often called to this important inquiry 
in the course of my public lectures on the applications of 
Science to the Arts, an apparatus of a very simple nature 
occurred to me, about two years ago, by which I hoped to be 
* Manchester Memoirs, vol. v. p. 563. 
Yy 
MDCCCXVIII. 
