RECENT COSMOGONIES 241 



just how far away the moon was thus hurled, but for the 

 sake of illustration we may suppose she was flung to a 

 height of some 4,000 miles, and we may further assume 

 that both parent and offspring were in the molten, or a 

 quasi-molten, state. Under these circumstances the two 

 bodies would doubtless raise great tides upon each other's 

 surfaces and these protuberances would, by their eccen- 

 tric attractions upon each other, retard the rotational ve- 

 locities of their respective globes. This would bring in- 

 to play the mysterious law of conservation of moment of 

 momentum, and the moon would consequently go out 

 further and further by way of compensating for her 

 slowly expiring axial rotating energy, until, finally, that 

 rotation would become reduced to a minimum and the 

 satellite would turn the same face constantly earthward 

 as it does now. 



Careful computations have demonstrated that on ac- 

 count of the relatively small mass of the moon, her tem- 

 perature under the impact theory could nothave exceeded, 

 at the very beginning, more than Farenheit. This 

 finding is plainly incompatible with the observed volcanic 

 rugosity of her surface. It is 'also to be noted that where- 

 as, in the order of size, we have the earth, Mars, and 

 moon, their order of roughness is, moon, the earth, Mars. 

 By deriving the moon from the earth, then, we may 

 theoretically endow the former with the same temper- 

 ature as our 80-times more massive planet. When, now, 

 we take into consideration the fact that the lunar gravity 

 is only about 1-6 of the terrestrial, it is easy to see why 

 the explosive effects on the satellite have been so much 

 more telling than upon either Mars or the earth. 



Inasmuch as the nebular earth did not give birth to 

 the moon as early in the process of condensation as did 

 the other planets to their satellites, but reserved its en- 

 ergies until it had attained a very compact stage and, 

 under the law of moments, a commensurately high veloc- 

 ity, it was only to be expected that the child should prove 

 the Titan it did. 



