88 THE ORIGIN OF LIFE 



down to us, than new wine is like old, or than the 

 new-born baby is like the veteran of three score 

 and ten. 



In reference to these artificial cells it may in 

 passing be remarked that the recent experiments 

 of Professor Tommasina of Geneva, as described 

 at the recent International Congress of Radio- 

 logy at Li^ge, on the radio-activity of animals 

 and plants, small though this activity may be in 

 living bodies are indeed remarkable, and quite in 

 accordance with the views which we have all along 

 maintained. It is measurable as much as, if not more so 

 than, the now well ascertained radio-activity of metals 

 generally, and of many other substances, and is much 

 larger than that which would be passed over with 

 indifference or escape the attention of any acute 

 observer. Now if in the first instance life arose by 

 the spontaneous action of some radio-active bodies 

 upon certain media possessing the ingredients of pro- 

 toplasm, it might be expected that the radio-active 

 nucleus would remain attached to the living body and 

 that radio-activity would be one of its properties. 

 Considerable induced radio-activity would also exist 

 in the substances which diffused outwards from 

 the nucleus, this induced radio-activity disappearing 

 altogether with time, and being renewed again by the 

 circulation or diffusion of fresh substances. The life 

 of the radio-active atom, however, is something of 

 the order of a thousand years, and if life originated 

 in this way, it is not easy to see how living things 

 could still retain their radio-activity, nor indeed how 



