THE ORIGIN OF LIFE 7 



of light, which might exert on such small 

 bodies pressure sujBScient to carry them 

 to the outermost limits of our solar sys- 

 tem. Thus interstellar space might con- 

 ceivably be peopled with spores which 

 could come in contact with any heavenly 

 body that had reached a stage in its de- 

 velopment at which life could be sup- 

 ported. 



It has been objected that the spores 

 might be killed by intense cold, dryness, 

 lack of air, or the action of light. But 

 some spores are resistant to these influ- 

 ences and it is by no means certain that 

 they could not survive a long time in in- 

 terstellar space. 



The theory of Arrhenius stands out 

 as a stimulating example of speculative 

 thought. It is inspiring to picture life, 

 taking flight from worlds outworn to 

 fresh fields in younger planets, and per- 

 sisting as long as the universe can har- 

 bor it, in cycle on cycle of endless progress. 

 We may admire this beautiful theory as a 

 splendid achievement of the creative 



