'World after world, sun after sun, star after star are past, Yet systems round in myriads rise more glorious than the last: The wondrous universe of God still limitless is found, For endless are its distances, and none its depths can sound!'" CHAPTER XXI OUR FIRST VIEW OF THE EARTH FROM MARS--A MARTIAN COURTSHIP Within a few days we had our first glimpse of the earth from Mars. It appeared only as a very thin but bright crescent of light, as the lighted portion was less than one-twelfth part of the whole diameter of the disc, and it was only visible for a very short time. Owing to the clear and thin atmosphere of Mars there is very little scintillation of the stars, and the crescent form of the earth at such periods as the present can plainly be discerned without the aid of a glass. To the Martians this is more readily seen than by us, as their eyes, being larger than ours, have a much greater light grasp. For the same reason all the stars shine much brighter than they do in our skies, and many of the smaller ones which can be seen from Mars with the unaided eye, would here require a low power-glass to render them visible to us. The fact that Saturn has a ring is quite apparent to the Martian eye. Day by day after this we saw the lighted area extending upon the earth, just the same as on the earth Venus can be seen with a telescope gradually to pass from the crescent phase to the gibbous form, and ultimately become full. Our earth is a morning and evening star to Mars the same as Venus is to the earth, according to its position with regard to the sun. Whilst we were looking at the earth, I asked Merna "Whether he had ever seen the earth transit the sun as we occasionally see Venus or Mercury do so?" He answered that "He carefully observed the last transit, which occurred on a date equivalent to our 8th May 1905, and was very interested in watching the earth pass, as a small black spot, across the sun's disc. The moon did not commence to cross until 6 hours and 7 minutes later, by which time the earth had passed over three-quarters of the sun's diameter. The earth was 8 hours and 42 minutes in transit, and the moon, which crossed a little lower down, was 8 hours and 31 minutes in crossing." "That must have been an interesting sight," said John, "and I should like to have the opportunity of watching a similar transit." "I am afraid you never will," said Merna, "for the transits only occur at long intervals. The previous transits occurred in November 1879, November 1800, May 1700, and May 1621. There will not be another until May 1984, and the next after that will not occur until November 2084." "I am sorry to hear that," remarked John, "for even if I stayed here, I should not be likely to live long enough to see the next transit. Possibly you may do so, Merna; you are so much younger than I am."