THE DEVELOPMENT OP THE PLANT 53 



nitrogen and carbon. Now cyanogen is only produced 

 at intense heat, and it is thought that great quantities 

 of cyanic substances must have been formed when our 

 earth was at a white heat. Hydrocarbons would be 

 formed in the same way, and the primitive atmosphere 

 and (later) ocean contained an abundance of salts. By 

 the time that the ocean settled on the crust the in- 

 gredients of protoplasm would be present in plenty, 

 and the natural energies then at work were peculiarly 

 intense. 



Further than this it is not yet possible to go. We 

 can only give a vague indication of possibilities which it 

 is quite hopeless to attempt to trace in detail. None of 

 the many attempts to describe the origin of life in detail 

 are at all satisfactory. The condition of the earth was 

 so different at that time from even the most artificial 

 conditions set up in the laboratory that the man of 

 science usually declines to consider the problem. If 

 ever science can raise a large quantity of mixed matter 

 to a temperature of 7,000 degrees or so, let it cool 

 gradually, subject it to a pressure of 250 atmospheres, 

 quicken it with electrical energy and radio-activity at 

 the due intensity, etc., it may have some chance of 

 reconstructing the story of the origin of life. Until then 

 it is content to say : If evolution accounts for the rise of 

 the most complex chemical compounds out of a simple 

 ether, and if it equally accounts for the advance of the 

 highest animals out of the simplest microscopic organism, 

 we assume that the comparatively short and obscure 

 link between the two was also a matter of evolution. 



It is now clear that we must equally dispense with 

 definite answers to our other two questions. There was 

 no " first " organism, and there was no point of time at 

 which life could be said to make its appearance. From 

 the fire-mist onward some of the material of the earth 



