10 INTRODUCTION. 



shores ; the deluging torrents of rain and mud, and the delusive pe* 

 riods of repose, between the eruptions, sometimes extending to years, 

 and centuries, are among the principal circumstances which charac- 

 terise volcanos. 



ATTRACTION AND REPULSION, although less obvious than some of 

 those phenomena that have been mentioned, are undoubtedly, more 

 important in relation to the system of things, than any or all other 

 natural causes and events. 



Gravitation is the bond which connects, equally, the greatest and 

 the minutest parts of our system. Every particle of matter gravi- 

 tates towards every other ; every mass, however large, is attracted 

 by every particle ; every member of our system, and every sys- 

 tem, in the great system of systems is affected, reciprocally, by 

 every other : projectile power, or immense distance and counter- 

 balancing attractions keep them from rushing together in ruinous col- 

 lision ; and the whole creation of matter is afloat in space, suspend- 

 ed and sustained by the energy of almighty power. 



It would be foreign to our present purpose, to designate the de- 

 tails of the various kinds of attraction the gravitating, the electri- 

 cal, the cohesive, the chemical, and the magnetic. 



The magnetic is universally known, and by its aid we traverse the 

 ocean and pathless deserts. It presents the most striking and famil- 

 iar example of repulsion, a power, which, springing from various 

 causes, and operating under various forms, is, although unseen, every 

 where active around us. We do not certainly know, that magne- 

 tism can be permanently attached to any other substances than iron 

 and nickel,* although we can no longer entertain a doubt, that it 

 holds a permanent connexion with heat, light and electricity. 



Attraction is only a name for an unknown cause, of which we have 

 no other knowledge than that it depends on the will of God. Mys- 

 terious indeed It is, but it is not more so than the connexion of our 

 intelligent minds with our living bodies. The Creator can endue mat- 

 ter with any properties, and there are, undoubtedly, many possible 

 qualities, which he has not bestowed, and many actual ones, which 

 we have not discovered. 



ASTRONOMY examines the heavenly bodies, and the construction and 

 relations of the celestial systems. It has taught us that the diffuse light 

 of the Galaxy is composed of the mingled effulgence of innumerable 

 stars, each of which is, probably, the centre of a system, and the con- 

 tinually increasing power of penetrating into space, acquired by the 

 modern improvements of the telescope, evinces, that we have only 

 begun to number the stars, and that we shall never be able to call 



Some add cobalt. 



