FORMA TION OF ME TE OKI TES 3 § I 



initial brilliancy must be much greater and the cooling to invisi- 

 bility much more prolonged.^ To phenomena of this class may 

 perhaps be tentatively assigned certain of the temporary stars. 

 Obviously these can only be such as had no prior visibility, and 

 such as sink sooner or later again into invisibility. Whether 

 this invisibility were due to the superficial cooling of the nucleus, 

 or merely to a deep enshrouding of cooled vapor, would be 

 immaterial. 



It has already been indicated that a possible result of the 

 serious disturbance of one solar system by the near transit of 

 another would be a fall of some of the disturbed planets upon 

 one of the suns. This also might be an ulterior rather than 

 an immediate result, through the modifying effects of other 

 planets, as well as the direct effects of the primary disturb- 

 ance. Such a fall must be presumed to give rise to a notable 

 increase of heat in the central body, as well as to mechanical 

 effects, both of which would be conditioned by the mass and 

 velocity of the secondary. An outburst of greater or less bril- 

 liancy must be presumed to be the result. The mechanical 

 effects upon the sun would probably involve great changes in 

 temporary density and condition, as well as outshoots of hot 

 gases in various directions at high velocities. The effects might 

 thus coincide with the phenomena of that class of the temporary 

 stars in which a luminous state precedes and follows the out- 

 burst, and in which varying densities or high velocities in 

 opposite directions seem to attend the temporary brilliant 

 stage. 



The disruption of suns has been neglected thus far. While, 

 under the terms of the hypothesis, the disruption of these 

 bodies must be rarer events than the fragmentation of the 

 more numerous small bodies, the results must be correspond- 

 ingly more important, by reason of their magnitude and char- 

 acter. 



It has already been observed, in passing, that the internal 



'Such a body 3.s Jupiter m\ght perhaps, under proper conditions, be dispersed 

 in the same manner as a sun as sketched beyond. 



