606 Transactions. — Miscellaneous. 



be certain that the planets are inhabited. We know little 

 more than this : Mars, the planet best situated for observa- 

 tion, has little or no atmosphere, and therefore, if inhabited, 

 must be so by creatures not formed like human beings. There 

 may, however, be some slight or thin atmosphere, as some- 

 times light shadows that appear like vapours have been seen 

 on the planetary surface ; but even on this point the best ob- 

 servers are doubtful. The polar ice-caps, known since the 

 days of Herschel, do undoubtedly diminish during the Mar- 

 tian summer. Mr. Douglas, of Lowell Observatory, has 

 remarked a dark edge to the melting ice, probably the water 

 into which the ice is converted. This is not certain, because 

 the polar caps may not be of ice at all ; they may be of solid 

 carbonic acid. The most eminent physicists doubt whether 

 the sun's rays would have power to melt more than a few 

 inches of snow or ice at the Martian poles. The greatly 

 disputed canals of Schiaparelli are still considered unproven. 

 The word " canal " is a mistranslation of Schiaparelli's word 

 " canale" ; this, in Italian, does not mean "canal," but 

 "channel," or watercourse. Some astronomers show these 

 channels on their maps of Mars as sharp dark lines passing 

 from point to point on the planet's surface ; but Barnard, 

 of the Lick Observatory (one of the most reliable observers, 

 and aided by one of the largest telescopes in existence), 

 says that the so-called channels are indistinct markings 

 too hazy and undefined to be reproduced ; this, too, 

 when he is able to give other details not mentioned by 

 Schiaparelli. A curious thing concerning the controversy 

 is that some of the observers of the so-called canals in 

 Mars are able to distinguish similar lines not only on Mer- 

 cury and Venus, but even on the satellites of Jupiter. The 

 more cautious and conservative astronomers hesitate even 

 yet to accept the Martian canal system, and one of them 

 has caustically remarked that if you wish to see the canals 

 well at night you must fix your eyes all the preceding day 

 on Schiaparelli's map. 



The spectroscope in the hands of Keeler has made us 

 acquainted with the fact that the outer portion of the rings 

 of Saturn revolve more slowly than the inner. This implies 

 that the rings are not composed of coherent matter, either 

 solid or liquid, but of a cloud of minute particles, perhaps of 

 a vaporous character, each moving in its own orbit. 



It is, however, in the domain of the fixed stars that the 

 most interesting facts have been brought to light, and as 

 spectrum analysis aids the telescope it is to be hoped that 

 even greater wonders will be presented to our grasp. The 

 most marvellous lesson revealed yet is as to the presence of 

 dark, and therefore invisible, bodies in the stellar spaces, and 



