134 On the Formation of the Universe, 



necessary that the condensed parts, most remote, should by 

 the motion of the aerial parts, be most turned out of a direct 

 course towards the centre of the nucleus ; and the supposi- 

 tion is perfectly reasonable, that the deviation might be so 

 regulated, that all, or nearly all of the condensed bodies 

 would strike the central nucleus in a tangent to its circumfer- 

 ence. By the expulsion of heat and light a compression 

 would take place in the nucleus a little different from that in 

 the aerial part of the wheel, but the same in effect. The 

 various portions of the nucleus, having acquired a degree of 

 actual velocity, would merely by their approach to the cen- 

 tre, increase the angular velocity oi the nucleus. It is obvi- 

 ous that the motion derived from this complex source in the 

 nucleus, would not stop at its surface, but would be constant- 

 ly conveyed by means of friction between the concentric 

 strata, to the extreme circumference of the aerial wheel, till 

 the angular velocity become uniform throughout. While 

 this complex process was going on in the planetary wheel, it 

 would collect a belt of the ejected matter from all parts of its 

 orbit, whose width would depend on the extent of that orbit, 

 or the quantity of matter ejected within given limits from the 

 solar wheel, and likewise in some degree on the rapidity of 

 condensation. Great extent of orbit, great quantities of 

 matter ejected within given limits, and rapid contraction in 

 the solar wheel, would tend proportionally to increase the 

 width of the belt ; while rapid contraction in the planetary 

 wheel would tend to diminish it. It is obvious that all the 

 causes favourable to great width of belt, except slow con- 

 traction in the planetary wheel, would belong peculiarly to 

 to the higher planets. If the planetary wheel should ac- 

 quire sufficient magnitude and motion, it would in its turn 

 eject portions from its circumference, in the same manner 

 as the solar wheel, and these portions would form its satellites. 

 The motion of the planets and satellites, both on their 

 axes and in their orbits, would be generally in the same di- 

 rection with each other, and with the equator of the sun. 

 Suppose P, fig. 1*, an accumulating planetary wheel, at the 

 same distance from the solar wheel as b. A body at b 

 would be equally liable to fall to the right or left towards P, 

 and of course the whole of the matter in the same circle as 

 b, would leave the direction of P's diurnal motion doubtful. 

 But as the solar wheel shrunk from P, its emitted portions 

 * See Plate at the end 



