AND LIQUIDS. 233 



matter of the sun being in an effervescent state, 

 small particles are thrown off, (as a steam from 

 boiling water,) and as these must act upon each 

 other, and upon the particles of the second" 

 kind of matter, many of them must constantly 

 be reflected back, and thus a current (a& before 

 mentioned) is continually setting in from the 

 extremity of the vortex towards the centre. 

 The particles thus thrown off, form both light 

 and heat. Such is the system, according to the 

 hypothesis of this author. But he sets out with 

 a supposition which can never be admitted, and 

 upon the truth of which his investigations de- 

 pend : that is, that the different parts of the 

 fluid, as it revolves about the sun, act upon 

 each other in proportion to their distances from 

 the sun, in the same manner as if they were 

 connected by an inflexible lever revolving about 

 the same centre. 



" M. SAUSSURE accounts for attraction, by 

 supposing that all space is filled with particles 

 of matter, moving rapidly in all directions ; and 

 that the particles which fall on the opposite 

 sides of any two bodies, in lines parallel to the 

 line joining to their centres, will impel the bo- 

 dies towards each other, the sides next each 

 other not being so acted upon. But, in this 

 case, the moving force of each body would de- 

 pend on the surfaces of the bodies ; whereas it 

 ought to be as the quantity of matter in each 



