DIASTROPHISM AND THE FORMATIVE PROCESSES 149 



views. These disclosures should help to lessen all hesitation in 

 accepting the view that our atmosphere is even now receiving solar 

 contributions. They should also lessen doubts as to the possibiUty 

 of the projection of great masses of sun substance to planetary 

 distances whenever stimulus is added to the spontaneous eruptivity 

 of the sun. 



MULTIPLE PHASES OF THE PLANETESIMAL HYPOTHESIS 



In these new disclosures there is the germ of a new phase of 

 the plane tesimal hypothesis, a phase that may possibly dispense 

 with aid from outside the solar system — heretofore supposed to be 

 necessary — and so make the origin of planets a wholly domestic 

 affair, though at present the suggestion does not look very promis- 

 ing. These disclosures seem to make the radial projection of the 

 matter requisite for a planetary system possible without stimulus 

 from outside. At the same time a transverse component of the 

 projection is indicated in what has just been said about the lateral 

 movement from the originating end of the arch toward the sun- 

 spot end. If this lateral movement should prove adequate, and 

 also be found to be preponderant in the right direction, it would 

 contribute the component necessary to the revolution of the 

 projected matter. The lateral movements in the two cases observed 

 were chiefly across the equator of the sun, that is, normal to the 

 required effect instead of coincident with it; but the position of 

 the arches transverse to the line of sight in these two cases may be 

 the essential reason why they were observed to such good effect. 

 Similar movements in the line of sight, and in the direction of the 

 sun's rotation, that is, the direction of planetary revolution, may 

 not only be as common as these, but even be the predominant ones. 



As the suggestion has only limited plausibility at present, it 

 need not be further deployed here, but as it offers the possibility 

 of a monoecious development of the planetary family in distinction 

 from the dioecious origin heretofore postulated, even the shadow 

 of such hypothesis is welcomed to a place among the multiple work- 

 ing sub-h3^otheses that make up the planetesimal genus. Arranged 

 with other developments of hke order, the group of such sub- 

 h3rpotheses embraces the following : 



