THE PLANET OF WAR. 



3(37 



living creatures — all these stages of the planet's 

 existence belong to the domain of geology and 

 biology, not to that of astronomy. Doubts have 

 arisen respecting the duration of these eras, and 

 as yet these doubts remain. Nor have biologists 

 as yet determined how long life may be expected 

 to continue upon our earth. Some see already 

 the signs of what may be called biological de- 

 crepitude. It has been asserted that man, the 

 highest race of living creatures which the earth 

 has yet known, is not only the highest she will 

 ever know, but that the race, regarded as a type 

 of animal life, has already passed its prime, and 

 has advanced perceptibly toward decadence. 1 

 Lower races, however, seem capable almost of 

 indefinite multiplication — we refer, be it under- 

 stood, to the multiplication of races, not of the 

 individuals composing races. And so far as mere 

 life is concerned, it would seem as though the 

 earth might undergo vast changes of condition, 

 and the sun himself lose largely in heat-emitting 

 and light-emitting power, without the earth being 

 depopulated, so long at least as the changes took 

 place gradually. It may well be that life begins 

 at so early a stage of planetary development and 

 continues to so late a stage, that the entire dura- 

 tion of a planet's life-bearing era bears a much 

 greater proportion to the entire duration of the 

 planet than our reasoning (a few paragraphs 

 back) implies. 



But, after all, the question of mere life in 

 other worlds is not what we are interested in. 

 Mere consciousness can scarcely be regarded as 

 a more interesting phase of Nature than uncon- 

 scious activity such as we see in the vegetable 

 world, or than the motion of inert matter, or even 

 than the mere existence of matter. If we could 

 be assured that Mars and Venus and Mercury 

 are crowded with animal and vegetable life of 

 those lower forms which owe their inferiority to 

 decrepitude of the type, or that on the youthful 

 planets Jupiter and Saturn some of the monstrous 

 forms exist which flourished on the earth when 

 she was young — 



" . . . . Dragons of the prime 

 That tear each other in then- slime, 1 ' 



1 One of the evidences for this discouraging conclu- 

 sion, advanced by a well-known American zoologist, is the 

 relative length of the period of old age in the individual 

 man. In youthful races, the individual does not attain old 

 age till very soon (relatively to the entire life) before death. 

 The relative duration of old age grows longer and longer 

 as the race grows older, until, in races which are about to 

 pass away, it becomes nearly equal to half the entire in- 

 terval between birth and death, soon after which the race 

 dies out. • 



what to us would be those teeming worlds of life ? 

 They might as well be mere inert masses circling 

 idly round the sun, neither now nor ever in the 

 past the abode of life, and never to become so in 

 future ages. The story of such life would be to 

 us as — 



". . . . A tale 



Told b}' an idiot, full of sound and fury 



Signifying nothing." 



It is the existence of intelligent beings on those 

 remote worlds that alone has any interest for us, 

 the thought that the wonders of the universe are 

 recognized by beings in some sort like ourselves, 

 that the problems which perplex us may have 

 been dealt with, perchance even solved, by others, 

 and again that our world may be a subject of in- 

 terest and study for creatures thinking as much, 

 but knowing as little, about us as we think and 

 know about them. 



In this respect certainly, if analogy can be 

 any guide at all, we find little reason for regard- 

 ing with present interest either the younger giant 

 planets, Jupiter and Saturn, or the probably aged 

 dwarfs, Mercury, Mars, and our moon. Few be- 

 lieve that men have existed on the earth many 

 hundreds of thousands of years, and those even 

 who assign to the human race its greatest dura- 

 tion in the past, regard it in its earliest form as 

 little better than a race of brute beings. If we 

 supposed that men sufficiently intelligent to con- 

 sider the heavens and the earth have existed in 

 our world for one hundred thousand years, we 

 are certainly giving the widest possible allowance 

 of duration to intelligent man. Nor can it be 

 denied that the existence of such a race as ours 

 seems far more definitely limited in the future by 

 the slowly-changing condition of our earth and 

 the life-giving sun, than that of lower types of 

 animal existence. We would not assert that 

 beyond all question a hundred thousand years 

 hence the earth will no longer be a fit abode for 

 man, who has already begun to draw very largely 

 on the garnered stores of our globe ; but we con- 

 sider this view altogether probable, and that in- 

 deed a nearer limit might be assigned to the 

 duration of the human race, by one who should 

 carefully consider the progress and requirements 

 of the race on the one hand, and the condition, 

 changes of condition, and capabilities of our 

 earth, on the other. 



If we assign 200,000 years as the extreme 

 duration of the period during which men capa- 

 ble of observing the phenomena surrounding 

 them and of studying the problems of the uni- 

 verse have existed and will exist, we assign 



