LIMITS OF LIFE. (ft 



heat-scale our Earth-life is confined. It may 

 be added that our sun is bv no means the 



V 



hottest star, but it is reported by authori- 

 tative scientists to be about half burnt-out, 

 having already dissipated the moiety of its 

 heat-giving energy. 



In the fourth place, as regards Time, Life 

 is and has been confined in what seems im- 

 passible limits. We at this moment exist be- 

 cause the Earth is cooling off ; once it was too 

 hot, hereafter it will be too cold, according to 

 scientific prophecy. Thus Man, and indeed 

 the total Earth-life is limited at two temporal 

 boundaries in the Past and the Future, and is 

 properly moving through a transitional stage 

 of the globe, from the beginning to the end 

 of the organic world. It is supposed that this 

 Earth-life started about one hundred million 

 years ago at which time our original ter- 

 restrial fire-ball had cooled down to a point 

 which not only permitted but possibly gen- 

 erated the first protoplasmic vital stuff (Pro- 

 tobioticon) out of which have evolved all the 

 plants and animals of the geologic ages down 

 to the present moment. A long period had 

 elapsed doubtless several hundred millions 

 of years before this epoch of terrestrial 

 vitality arrived. At what turn of the asons 

 the Earth-life will expire is of course conjec- 

 tural; some say another hundred million 



