408 G. R. Wielaiid — Polar Climate in Time. 



lower forms of life at tlie poles and their later appearance at 

 the tropics would also be lengthened by the greater heating 

 power of the sun at the equator, a factor doubtless greater 

 then than now. In any case the critical temperature and the 

 stability necessary even to hot water life may well have required 

 a million years to slowly move southward to the equator, after 

 an initial appearance at the poles. And the highly interesting 

 view that the requisite physical conditions of life did actually 

 first appear and inaugurate life itself at the north pole, and 

 that as the result of evolution in the northern circum-polar 

 area new species were continually dispersing from thence 

 southward throughout time down to the glacial period, was 

 ably presented by Mr. G. Hilton Scribner, more than twenty 

 years ago.''^ Wlien Mr. Scribner wrote, the work of G. 

 H. Darwin had not yet appeared, and while overlooking 

 the part that tides must have played in preventing equatorial 

 stability and thus have been the main factor in preventing 

 early equatorial life, his chief conclusion is regarded as funda- 

 mentally correct, and to him belongs the credit of its first 

 enunciation. Though it seems quite clear that life could as 

 reasonably have had a similar beginning at much the same 

 time at both the poles. 



The causation of this assumed early polar origin of life, has 

 of course a direct bearing on the view of climate here pre- 

 sented. But without indulging at present in speculations how- 

 ever interesting, I shall only say in passing that we cannot 

 admit that the properties of primal protoplasm, whether of 

 mundane or extra-mundane origin, depend on anything else 

 than the physical, electrical, chemical, vital and other proper- 

 ties of matter. ^^ Ex niliilo nihil fit. ^^^ 



* Where Did Life Begin ? New York : Charles Scribner's Sons, 1883. 



f The theory that the origin and entire course of life is wholly based on 

 the properties of matter mnst be held as the most comprehensible, even if 

 life was actually transplanted from some other sphere, for thus pushing its 

 origin back a stage leaves us in precisely the same position as before. But 

 that life may have originated very remotely and have reached this globe, 

 perchance, from other celestial bodies is not utterly without the bounds of 

 reason, as suggested by the experiments of Professor Dewar and Sir W. T. 

 Thiselton-Dyer, showing that seeds (and spores) have wonderful resistant 

 power to cold. These experimenters placed the seeds of flowering plants in 

 vacuo at —250° to —253° C, a condition approximating outer space, with- 

 out greatly affecting their vitality, — a good proportion of the seeds which 

 had been thus passed through a sub-crystalline state afterward growing when 

 planted. Other seeds were soaked in liquid hydrogen and afterward germi- 

 nated, as did yet others after immersion in liquid air contained in a red hot 

 platinum dish ! 



It is above all things conceivable in the light of such experiments that 

 virile spores and resting stages of lowly organized forms maj^ have reached 

 this globe from the outer space at any time in its history, or indeed may 

 still be reaching it for aught we can say, in the vastest numbers. The " red 



