CHAPTER XII. T/ze Laws of illugnetisnz.

MAGNETISM has no very obvious 0r apparently extensive office in the mechanism of the atn1os- phere and the earth : but the mention of it may be introduced, because its ascertained relations to the other powers which exist in the system are well suited to shew us the connexion subsisting‘ throughout the universe, and to check the sus- picion, if any such should arise, that any law of nature is without its use. The parts of creation when these uses are most obscure, are precisely those parts when the laws themselves are least known.

\Vhen indeed we consider the vast service of which magnetism is to man, by supplying him with that invaluable instrument the mariners compass, many persons will require no further evidence of this property being introduced into the frame of things with a worthy purpose. As however, we have hitherto excluded use in t/ze arts from our line of argument, we shall 11ot here make an exception in favour of navigation, a11d what we shall observe belongs to another view o1 the subject.

Magnetism has been discovered in modern