Feb. 12, 1874] 



NATURE 



287 



MARS 



'X'HE characteristic appearance of this planetary body, 

 ■•■ long famihar to astronomers, has of late become 

 generally known. Remarkable neither for situation, mag- 

 nitude, brilliancy, retinue or complexity of arrangement, 

 inferior in each of these respects to some, and in many of 

 them to several of the members of the solar family, one 

 circumstance alone invests it with a peculiar interest — its 

 resemblance to ourselves. Such a resemblance obviously 

 does not exist in the mightier and more nobly attended 

 external planets : the banded skies of two and the strong 

 atmospheric absorption of the two others revealed by the 

 spectroscope, sufficiently show that they belong to classes 



mutually indeed dissimilar, but each dififering, and per- 

 haps widely, from our own. With the swift and 

 fiery Mercury we can have as little sympathy ; and 

 though Venus would offer a more promising analogy, 

 the configuration of her beautiful surface is not well seen 

 or readily interpreted. Mars therefore remains ; and 

 while, fortunately for astronomers, he occupies such a 

 position that his features are fairly accessible, they bear 

 an aspect so comparatively intelligible that, whatever may 

 be the case as to our other fellow-subjects in the solar 

 monarchy, we are ready to claim that globe as a close re- 

 lation of our own, inferior indeed in magnitude and im- 

 portance, if importance is indicated by an attendant, but 

 arranged in a corresponding manner by the Great 

 Creator as the seat of life and intelligence. 



Such a supposition has been gradually and surely ad- 



vancing from an early period of telescopic astronomy. 

 The polar whiteness detected by Huygens and Cassini I. as 

 far back as 1672 would natu'-ally suggest the idea of a 

 snowy deposit, which assumed almost the form of cer- 

 tainty, when the elder Herschel shoived that its extent 

 was regulated by the Martial seasons, and that it wasted 

 steadily down with the advance of vernal heat. From 

 the obvious division of ihe surface into brighter and 

 darker portions, the existence of an atmosphere at least 

 would be inferred, so long as they were supposed to be 

 variable ; but as the evidence of their general perman- 

 ence increased under the eye of Herschel I. about a cen- 

 tury ago, this impression gave place to the more 

 definite recognition of something corresponding to the 

 outlines of lands and oceans, with occasional varia- 

 tion from atmospheric condensations ; and thus by 

 degrees we have been led to acknowledge, in that remote 

 and otherwise unimportant globe, a most interesting 

 counterpart of our own. 



This conclusion has not, however, been attained by an 

 uninterruptedly continuous or an uniformly satisfactory 

 process of deduction ; and even at the present time it is 

 perhaps not universally received. Schrotcr referred the 

 darker portions to atmospheric obscuration, a notion 

 which pervaded others of his investigations, not to their 

 advantage ; and a more recent observer of considerable 

 ability, the late Prof. Kaiser, of Leiden, whose decease in 

 his 64th year took place July 28, 1872, has, in a very ela- 

 borate and interrstitig report of the work done on the 

 planet at that observator)-, expressed his doubts as to the 

 certainty of the more customary inferenre Whatever 

 may be our own impressions on the subject, his criticisms 

 and conclusions exhibit so much of the genuine spirit of 

 an im,,artial student that some notice of them, as they 

 are found in vol. iii. of the Annals of the Leiden Observa- 

 tory, may be worth the attention of our readers. This 

 observator)-, it should be noted, is provided with a Merz 

 achromatic of 7 (French ?) inches aperture, and was there- 

 fore, under Kaiser's superintendence, fairly competent for 

 physical researches commensurate with the present de- 

 mands 01 science ; as it is well known, and indeed espe- 

 cially brought out by the observations we are about to 

 ■ I'tice, that much larger telescopes are not invariably, or 

 e'ei- generally, available in proportion to their magnitude. 

 The addition, in 1872 — too late therefore for a share in 

 he professor's observations — of an Si inch With Brown- 

 ng refiecior, will hereafier not only afford an interesting 

 comparison of instruments, but if the result corresponds 

 with others obtained elsewhere, will be found a step in 

 advance as regards efficiency.* 



In selecting Mars as the subject of special inquiry. Prof. 

 Kaiser laid a solid foundation by consulting every work 

 viihin his reach, representing or describing the physical 

 aspect of the planet, from the earliest- and rudest efforts 

 in 1636 to the < laborate delineations of the present day. 

 No less than 412 drawings thus passed through his 

 hands : upivards of 320 others he could not procure ; and 

 the aggregate is doubtless much in defect of the existing 

 total He did however well in securing so many ; more, 

 probably, than any other areographer, if such a word may 

 be allowed. But the result of their comparison and dis- 

 cussion was not as satisfactory as might be wished. The 

 first specimens of representation were of course mere rude 

 attempts. Those of Huygens, however, in 1659, disco- 

 vered by Kaiser in his ''day-book" (of which the most 

 valuable portion was edited by him in 1847) are compara- 

 ratively well drawn ; and Hook, in 1666, caught the true 

 character of what he saw, though Kriser doubts whether 

 his spots could be as readily identified as has been sup- 

 posed. We next find Herschel I. taking up the subject 



■ A curious I 



rhe part of Prof. Kaiser may h 

 of Mars by Browning 



i\ curious error on inc pari oi i^roi. rvcti 



.-eferred (p. 23) to a drawing of Mars by 



with a silvered mirror by Barnes. This gentlt 



of the speculum, which, like the others mounted Ijy tnat ( 



work of a most accomplished artist, Mr. With, of Hereford. 



: be 



Jticed. He 

 iving been l.^ken 



. ...^.^ly the proprietor 



ited by that optician, •■"'^ 'l' 



. th 



