# 
ad 
Terrestrial Magnetism. 101 
proved by the miasmata, which sometimes impregnate the at- 
mosphere, and yet baffle the skill of the chemist to detect them, 
although the disease which follows in their train establishes their 
existence. 
If we examine what are termed the magnetic fluids on the 
poles of the loadstone, it appears that we can neither see, feel, nor 
taste them, they are not easily disengaged from the particles of 
the iron, and the only proof of their existence is the attraction 
they exert. May not this difficulty in perceiving them, arise 
ftom their atoms being so exceedingly small, as to be apprecia- 
ble only to a higher order of senses than we are endowed with. 
Light and heat will pass through transparent bodies without much 
difficulty, but Mr. Haldat has shown that the magnetic fluids will 
hot only pass through transparent substances, but through all 
bodies, even the most dense ;—and from this I argue, that they 
are of greater tenuity than either light, heat, or electricity. 
_ The sun is continually emitting rays which reach the earth in 
immense quantities, and the question has been significantly _ 
asked, but not so easily answered, if they are material bodies, 
What becomes of this flood of light and heat? They do not ac- 
cumulate on the earth’s surface like snow, but disappear as fast as 
they arrive. It may be said they become latent. This sup 
that light and heat, as usually understood, are perceptions of the 
mind, and that the exciting causes of these sensations are un- 
known principles or substances, as evanescent and difficult to ap- 
Ptehend as the magnetic fluids themselves. Now, may it not be, 
that these substances hitherto incognita, are the identical ele- . 
nents or fluids, whose attraction causes the phenomena of mag- 
Hetism, and that instead of light and heat being mere sensations, — 
€xcited by we know not what, they are real material bodies, com- — 
Pounded of these and other elements. Ress 
There Suppose, that there are three elements ; one of which is 
ommon to light and also to heat; that light and heat are each 
Composed of two simple elements; and that when the ‘sun’s rays 
Teach the earth, they are decomposed by the attraction of the 
bodies on its surface, with which their elements unite, and from 
Which they can be again extricated by different processes. 
3 We know that light and heat can be obtained from almost 
“very form of matter, and the idea here offered to explain their 
Ppearance and reappearance, by a decomposition into simpler 
se 
