REPORT ON METEOROLOGY. 
197 
similar elements already in store. The amount of detached 
facts is absolutely appalling; and the consequence is, that not 
only in registers of individual observations, but in those where 
the results are presented in a condensed shape and the arith¬ 
metical means have actually been taken, but a few points have 
been applied in practice to the elucidation of any one theoreti¬ 
cal difficulty in the science. 
The most general mistake probably consists in the idea that 
Meteorology, as a science, has no other object but an experimen¬ 
tal acquaintance with the condition of those variable elements 
which from day to day constitute the general and vague result of 
the state of weather at any given spot; not considering that 
while such heterogeneous elements can be of little avail, when 
viewed simply as a group of facts, towards forwarding any one 
end of the science, or giving us any precise knowledge regard¬ 
ing it, yet that the careful study of the individual points, when 
grouped together with others of the same character, may afford 
the most valuable aid to scientific generalization. If instead of 
aiming at a rude approximation to the mean numerical ele¬ 
ments furnished by meteorological instruments for a particular 
spot, some individual branch were selected and pursued under 
the most favourable circumstances, a result would be obtained 
at no more expense of labour,—an insulated one it is true, but 
capable, by combination with others, of making a real addition 
to the deductions of the science. As this appears to me the 
place to insist upon a total revision of the principles upon which 
meteorologists have hitherto very generally proceeded, I shall 
explain my views a little more particularly. 
It is in the first place worthy of remark, that the most inter¬ 
esting views which have been given in this science, and the most 
important general laws at which it has yet arrived, have for the 
most part been contributed by philosophers w r ho, in pursuit of 
other objects, have stepped aside for a moment from their syste¬ 
matic studies, and bestowed upon the science of Meteorology 
some permanent mark of their casual notice of a subject which 
they never intended to prosecute, and which they soon deserted 
for other and more favoured paths of inquiry. Mr. Dalton de¬ 
scends for a moment from his chemistry in the abstract, to illus¬ 
trate the constitution of the atmosphere and the theory of vapour. 
Laplace, viewing nature with the eye of a master, introduces 
into his Mecanique Celeste an investigation of the mechanical 
structure and law r s of equilibrium of the gaseous envelope of 
our planet: he applies Meteorology to one of its great objects,— 
the laws of atmospherical refraction; and gives to the scientific 
w r orld a new formula for the measurement of heights by the 
