INTRODUCTION 11 



by the currents tending westward a supposition against which 

 the chances are as infinity to one the one set must eventually 

 prevail over the other. And after some such manner as this our 

 solar nebula must have acquired its definite rotation from west 

 to east. 



Why should we suppose, with Spencer, that the 

 flocculi would fall only so far, instead of the whole way ? 

 and then obligingly take to rotating in accordance,, TOfl. 

 Kepler's laws around a fixed axis; or why, with Jpisk^ 

 that haphazard currents proverbially fitful and inc,qn 

 stant would forswear haphazardness and docilely . ^re^ 

 volve in ideally-ordered curves! LortooJVri 



"But First Principles", the reader may intej/jec^ 

 "was published in 1860, and Fiske's book in 1874; doubt- 

 less something more definite and convincing .^hi^pe^n 

 forthcoming in the meantime." To satisfy the min^pn 

 this score I shall quote a late passage f rom $$ t jpep 

 Doctor T. J. J. See, the Director of the U. S/J^aJL' 

 servatory at Mare Island, California, and the autl^r 

 the so-called Capture Theory (Art. Cosmogony I ^J^v 



cana ) : .q ^01 



The solar system was formed from a spiral nebula, revolving 

 and slowly coiling up under mechanical conditions which were 

 essentially free from hydrostatic pressure. And spiral nebulae 

 themselves arise from the meeting or mere settling of unsymme^- 

 rical streams of cosmical dust. The whole system of particles has 

 a sensible moment of momentum about some axis, and thus ii tie- 

 gins to whirl about a central point, and gives rise to a vortex. 

 In the actual universe the spiral nebulae are to be counted by. the 

 million, and it is evident that they all arise from the automatic 

 winding up of cosmical dust, under the attraction of their mutual 

 gravitation. The two opposite branches of the spiral nebulae, sp 

 often shown on photographs, represent the original streams of 

 cosmic dust which are coiling up and forming gigantic spiral 

 systems. * * * The dust carried away (from the stars) by repulj- 

 sive forces gathers here and there into clouds, ajid when such a 

 mass settles the result is a cosmical vortex, which whirls ,anji 

 slowly develops into a cosmical system. Thus the r stars by the e^- 

 pulsion of fine dust form nebulae, and the nebulae in turn, by con- 

 densation, form stars and systems. The clusters*' like the whirl- 

 pool nebulae, have a tendency to spiral movement. The attend- 

 ant bodies, however, are never thrown off, but captured and 

 added on from without. The heavy bodies drift toward the 



