16 Mechanical Philosophy. 



^' cond time; and so on. The solid atoms are of 

 " different sizes and figures; so that, when one 

 ^' portion of them congeals, or forms into grains, 

 " there are pores among them large enough to 

 " permit atoms of a smaller size to pass freely 

 *' through. The condition of the matter of the 

 " heavens, under the action of fire at the sun, was 

 '' chamahj the streams of light from the sun, moon 

 ** and stars, were ashteroth; and the grains of air 

 " returning from the circumference of the heavens 

 " to the sun, was baallm. Concrete matter,- how- 

 '^ ever, is often so constituted as not to be perme- 

 *' able very easily, but to resist. The several sorts 

 " of atoms composing the fluid matter which oc- 

 *' cupies immeasurable space, are the moving 

 *' powers by which God acts upon and regulates 

 " the machinery of the universe. The more com- 

 " pact or unyielding modifications of it constitute 

 " the great orbs, or machines, to be urged along 

 " by their impulse. The latter are the chariots^ 

 *' and the former the drivers, AVhen, therefore, 

 " light, impelled by the sun, strikes the side of 

 " such a body as the earth we inhabit, it excites 

 *' heat in that part, and the spirit, or air, being 

 " rarefied, or made to recede thereby, motion is 

 ^' communicated to the whole orb. The motion 

 " thus begun, is promoted and continued by the 

 " vast and incessant pressure of the dark, cold 

 " and dense matter on the opposite side. And 

 " thus the globe being started by the lessening of 

 ''' pressure on one side, and the augmentation of it 

 '' on the other, its diurnal and annual revolutions 

 *' were soon impressed upon it by a little variation 

 '^ of the forces. The like reasoning he applied to 

 '' the moon, and to all the other planets and their 

 ^ satellites. By the operation of light, thus sent 

 " out from the sun, and acting upon the other fluid 

 '' matter of the heavens, and upon the celestial 



