200 
SECOND REPORT-1832. 
ing out some of the more important, and of the methods which 
should be taken for supplying them. It is much to be desired 
that other bodies as well as the British Association should use 
their influence to direct individual effort into the channel most 
likely to contribute to the advancement of science. In a period 
like the present, when the stream of knowledge seems to dimi¬ 
nish in depth as it increases in diffusion, it is above all neces¬ 
sary for influential bodies to retard the progress of that ten¬ 
dency to merely superficial study, which has injured nothing 
more than the science of Meteorology,—one which, though in 
many respects apparently simple and abounding in palpable 
results, really consists, in its very nature, of a most elaborate 
piece of mechanism, delicate in its parts, and of which the con¬ 
nexion is anything but obvious. 
The true basis of the science rests upon several branches of 
physics, which are only at the present moment rising to their 
true level of importance in the scale of human knowledge ; and 
there are few of the sciences which are not more or less directly 
connected with the progress of Meteorology. Astronomy bears 
not only the great relation of taking cognizance of the causes 
of change of season, but it gives the data for estimating the 
influence of the heavenly bodies in raising tides in our atmo¬ 
sphere, and indicates the causes of alteration of climate which 
some of their longer periodic motions present*. Geology 
teaches us the probable state of cooling from an intensely high 
temperature in which our globe now exists, which most 
likely exerts a material though till lately unsuspected influence 
upon climatology. Chemistry analyses the composition of that 
gaseous atmosphere, the modifications of which it is the princi¬ 
pal object of Meteorology to investigate. Pneumatics furnishes 
us with the grand laws which connect the pressure and den¬ 
sity of the air with height, which gives a key to many of the 
variations indicated by the barometer, and by means of that 
instrument enables us to attain an accurate comparison of differ¬ 
ent elevations in the gaseous medium. To the science of Elec¬ 
tricity we must look not merely for the explanation of those 
phenomena which more obviously indicate its presence and 
action, but likewise of many which at present are almost veiled in 
obscurity, or can be but partially explained by other agencies. 
But most of all is the science of Heat the very basis of all 
accurate knowledge in Meteorology. No one department is 
exempt from its influence ; no one substance in nature seems 
independent of the action of this subtile element. Impalpable 
though it be, yet since we possess such accurate means of in- 
* See Sir John Herschel on Astronomical Causes affecting Geology, GeoL 
Trans. N.S. iff 
