IS TEE MO OX DEAD? 



2 



to 



On the whole, then, if it cannot be regarded as 

 demonstrated (in its general bearing, of course, 

 for we cannot expect any theory about the pyra- 

 mids to be established in minute details), the as- 



trological theory may fairly be described as hav- 

 ing a greater degree of probability in its favor 

 than any hitherto advanced. 



— Belgravia. 



IS THE MOON DEAD? 



THE idea generally prevailing among astron- 

 omers respecting the moon's condition is 

 that she is a dead planet, an orb which circles 

 around the sun like her companion planet the 

 earth ; but is not, like the earth, the abode of 

 living creatures of any sort. Formerly, indeed, 

 other views were entertained. It was thought 

 that the dark regions were seas, the bright re- 

 gions continents — a view embodied by Kepler in 

 the saying, " Do maculas esse maria, do lucidas 

 esse terras." But the telescope soon satisfied 

 astronomers that there are no seas upon the 

 moon. It has been noted that in two well-known 

 passages of the "Paradise Lost," in which Milton 

 touches on the work of Galileo with the tele- 

 scope, he speaks of lands, mountains, rivers, and 

 regions, but not of oceans or seas, upon the 

 moon. Thus, in describing the shield of Satan, 

 he compares it to 



"... . the moon, whose orb 

 Through optic glass the Tuscan artist views 

 At evening from the top of Fesole, 

 Or in Val d'Arno, to descry new lands, 

 Rivers, or mountains, on her spotty globe." 



While again, in the fifth book, Raphael views the 



earth — 



" .... as when by night the glass 

 Of Galileo, less assured, observes 

 Imagined lands and regions in the moon." 



We may well believe that had Galileo, in his in- 

 terviews 1 with Milton, described appearances 

 which (with his telescopic power) resembled seas 

 or oceans, the poet would not have used so vague 

 a word as " regions " in the third line of the last 

 quoted passage, where the word " oceans " would 

 so obviously have suggested itself. From the very 

 beginning of the telescopic observation of our 

 satellite, it became clear that no seas or oceans 

 exist upon her surface. And as telescopic power 

 has increased, and the minute details of the 

 moon's surface have been more searchingly scru- 

 tinized, it has been seen that there are no smaller 

 water-regions, no lakes, or rivers, not even any 

 ponds, or rivulets, or brooks. 



1 See Milton's " Areopagitica." 



But, indeed, while the close telescopic scrutiny 

 of the moon was thus showing that there are no 

 water-surfaces there, it was becoming also clear 

 that no water could remain there under the sun's 

 rays — that is, on the parts of the moon which are 

 illuminated. For it was found that the moon has 

 an atmosphere so rare that water would boil away 

 at a very low temperature indeed. How rare the 

 lunar atmosphere is we do not certainly know ; 

 but a number of phenomena show that it must 

 be very rare indeed. Some of these have been 

 already considered, along with other lunar phe- 

 nomena, in an article which appeared in the Corn- 

 hill Magazine for August, 18*73 ; and for this 

 reason (especially as that article has since been 

 republished) we do not here enter into this por- 

 tion of the evidence, our object being to discuss 

 here certain relations which were not dealt with 

 in that earlier paper. 



But now that astronomers have almost by 

 unanimous consent accepted the doctrine of the 

 development of our system, which involves the 

 belief that the whole mass of each member of the 

 system was formerly gaseous with intensity of 

 heat, they can no longer doubt that the moon 

 once had seas and an atmosphere of considerable 

 density. The moon has, in fact, passed through 

 the same changes as our own earth, though not 

 necessarily in the same exact way. She was once 

 vaporous, as was our earth, though not at the 

 same time nor for so long a time. She was once 

 glowing with intensity of heat, though this stage 

 also must have continued for a much shorter 

 time than the corresponding stage of our earth's 

 history. Must we not conclude that after passing 

 through that stage the moon was for a time a 

 habitable world as our earth is now ? The great 

 masses of vapor and of cloud which had girt our 

 moon's whole globe, even as in the youth of our 

 earth her seas enwrapped her in cloud-form, must 

 at length have taken their place as seas upon her 

 surface. The atmosphere which had supported 

 those waters must at first have been dense by 

 comparison with the present lunar atmosphere, 

 perhaps even by comparison with the present at- 



