90 Chemical Works. 
_ of some of the elementary gases have been determined, with the aid 
of the most refined instruments, and with the most elaborate and scru- 
pulous correctness. It were to be wished, indeed, that this should 
be attempted onder the auspices of some one of those learned socie- 
ties, which have been instituted for the promotion of science ; and 
that the investigation should be confided to a commission of its mem- 
bers, whose skill, experience, and fidelity, would be a pledge for the 
accuracy of the results. The precise admeasurement of an are of 
the meridian was not more important to astronomical truth, than the 
exact determination of the specific gravities of the elementary gases 
is to chemical philosophy. 
‘With the importance of the foregoing observation we concur; 
and should be proud if the chief philosophical institution of our Scot- 
tish metropolis would take the lead in putting into execution so desir- 
able an object. 
“Tn the preface, the author has alluded to the deep loss which the 
scientific world has sustained by the death of Sir Humphry Davy 
and Dr. Wollaston, in a joint eulogium upon these two distinguished 
hilosophers, which is characterized no less by its just discrimination 
of their respective excellencies, than by its forcible eloquence: ‘It is 
impossible,’ says Dr. Henry, ‘to direet our views to the future im- 
provement of this wide field of science, without deeply lamenting the 
privation, which we have lately sustamed, of two of its most success 
ful cultivators, Sir Humphry Davy and Dr. Wollaston,—at a peri 
of life, too, when it seemed reasonable to have expected, from each 
of them, a much longer continuance of his invaluable labors. To 
those high gifts of nature, which are the characteristics of genius, 
and which constitute its very essence, both those eminent men united 
an unwearied industry and zeal, and researeh, and habits of accurate 
reasoning, without which even the energies of genius are inadequate 
to the achievement of great scientific designs. With these excel- 
Jencies, common to both, they were nevertheless distinguishable by 
marked intellectual peculiarities. Bold, ardent, and enthusiastic, 
Davy soared to greater heights; he commanded a wider horizon; 
and his keen vision penetrated to its utmost boundaries. His ima- 
gination, in the highest degree fertile and inventive, took a rapid and 
extensive range in pursuit of conjectural analogies, which he submit- 
ted to close and patient comparison with known facts, and tried by 
an appeal to ingenious and conclusive experiments. He was imbued 
with the spirit, and was a master in the practice, of the inductive 
