92 LECTUKES ON BIOLOGY 



for the existence of life no living beings existed. There were 

 solid and disintegrated rocks, water, and air all around, a warm- 

 ing and illuminating sun, and everything ready to become a 

 garden. Did grass, trees, and flowers in all their wealth of 

 variety and beauty spring into existence by the fiat of a creative 

 power, or did vegetation originate from seeds which had been 

 sown upon the earth ? 



" If a volcanic island emerges from the sea and after a few 

 years is clothed with vegetation we do not hesitate to believe 

 that the seed was carried to it through the air or by the sea. Is 

 it not possible, and, if possible, is it not probable, that the begin- 

 ning of plant-life on earth can be explained in a similar manner ? 

 Each year there fall upon the earth thousands, probably millions, 

 of fragments of solid matter. Where do they come from ? 



" If two large bodies collide in space it is certain that a large 

 part thereof is fused, but it appears equally certain that in many 

 cases a large mass of debris must be hurled in all directions ; and 

 that among them many suffered no greater injury than parts of 

 a rock in a landslip, or during blasting operations. If the 

 moment when our earth collides with an equally large body 

 should occur whilst it is still clothed with vegetation, many large 

 and small fragments bearing seed, living plants and animals 

 would doubtless be distributed throughout space. Therefore, and 

 because we all firmly believe that there exist at present, besides 

 our own, many other worlds with life, and have existed since 

 time immemorial, we must regard it as highly probable that 

 innumerable seed-bearing meteorites are moving through space. 

 If, therefore, no life existed upon earth at this moment a 

 meteorite falling upon this planet would lead to the production 

 of vegetation by what we call a natural cause. 



" The hypothesis that life originated on our earth through 

 seed-bearing fragments from the ruins of another world may 

 appear strange and fanciful, but I contend that it is not 

 unscientific." 



The theory of a cosmic origin of life on earth arose probably 

 from the fact that it is sometimes possible to demonstrate in 

 meteorites traces of carbon compounds equal to those which 

 come from organisms. Even humus-like matter has been found 

 preserved in the interior of meteorites. If these formations were 



