370 KANSAS ACADEMY OF SCIENCE. 



Flagstaff, Ariz. This much seems reasonably certain : there is a 

 polar cap of snow that waxes and wanes with the round of seasons, 

 and these canals and seas increase with the melting of this snowy 

 mantle. What are thought to be clouds have been observed in the 

 Martian atmosphere, and some claim to have seen the actual deiDosi- 

 tion of snow from these clouds. Mars is undoubtedly the most like 

 our earth of any of the easily observed planets, and very probably 

 furnishes suitable conditions for some kind of life. Professor Hall, 

 of Washington, D. C, made the remarkable discovery of the two tiny 

 satellites, which Swift, in "Gulliver," so wonderfully predicted, as to 

 size and distance. This feat of astronomical detective work is said to 

 be as difficult as the recognition of a tennis-ball at the distance sepa- 

 rating Boston and New York. 



The curious little planetoids have been multiplied until they num- 

 ber about 500, and the discovery of a new one is treated with indiffer- 

 ence, unless, like one of the last, Eros by name, it presents some 

 anomaly of position or motion. The plane of this planetoid's orbit 

 makes an unusually large angle with the ecliptic, and it passes in one 

 part of its path within the orbit of Mars, thus becoming our nearest 

 visitor, excepting the moon. Concerning the outer planets, not much 

 has been added within recent years. Barnard signalized the excel- 

 lence of the Lick telescope by ferreting out the fifth satellite of 

 Jupiter; and one of the Pickerings has found the ninth satellite of 

 Saturn, naming it Phoebe. Professor Keeler, who succeeded Barnard 

 definitely proved by the spectroscope that the rings of Saturn are 

 neither solid nor liquid, but meteoric in form. These rings are prac- 

 tically annular masses of tiny satellites circling about the planet. 

 They are supposed by some to be moons in process of formation. If 

 so, we are witnessing the manufacture of worlds in God's workshop. 

 This was thought at one time to be the normal form assumed by the 

 primal nebul?e in all cases of world-formation, but, as we shall note 

 later on, it is probably an anomalous condition. Saturn itself is still 

 in embryonic state, as shown by its low specific gravity, and the other 

 major planets are in the infant stage of development. The famous 

 red spot of Jupiter has greatly diminished in size and brilliancy. 



During the early half of the nineteenth century it was gravely sug- 

 gested that the cometary visitors to our system were "excursion trains" 

 for the especial delectation of those astronomers who had "come up 

 through great tribulation," and who wished to inspect the stellar uni- 

 verse at closer range. These supposed trains, with their gala-day 

 banners, went whisking now through this and then that solar system. 

 These excursion trains, through good telescopes and in the spectro- 

 scope, look strangely like the other commonly distributed nebulous 



