ORIGIN OF LIFE ON THE SHORES OF THE OCEAN 107 



only recently come to see the importance of providing for its very 

 early stages. The essential feature is to move from concentrations 

 of one part per million, let us say, to concentrations of between 1 

 and 10%. The most obvious way of doing this would be just to 

 take the sea water and boil it down or evaporate it in sunlight, 

 and this has been often postulated : it might be called the rockpool 

 origin of life which was favored by Darwin himself. I have never 

 been happy about this because it is difficult to see what happens 

 after the rockpool has dried out, for although it may be filled again 

 by another tide, anything formed in it will be washed out again 

 and dispersed in the ocean. Consequently, it did not seem to be a 

 very plausible mechanism, but I had not until quite recently come 

 across a better one. Now another and more promising explanation 

 can be derived from the very ingenious investigations of Wilson 

 (1959a,b). He, while studying the composition of snow in the 

 New Zealand mountains, noticed that it contained two features 

 that seemed to him unusual, namely a large content of organic 

 nitrogen and a much larger ratio of potassium to sodium than 

 occurs in most sea waters. This he attributed, by a number of 

 ingenious experiments, to the origin of the snow or the rain in 

 sea mist. This has been known as far as the salt is concerned for a 

 very long time, for it is admitted that most of the salt lakes near 

 the sea and even the sulfur lakes there are produced by the 

 carrying over of dried-out sea mist containing chlorides and 

 sulfates. The most interesting and new deduction, however, of 

 Wilson is that, because the composition of this mist is not the same 

 as that of sea water in bulk, particularly with regard to its content 

 of organic material and potassium, he concluded that he was 

 studying, not a sample of the sea in bulk, but a sample of the 

 surface of the sea. He checked this by an analysis of sea foam, 

 where he found correspondingly large amounts of these constit- 

 uents. In respect to sea foam it was fairly evident that here were 

 collected a large number of microorganisms, largely dead organisms, 

 but also living bacteria from the surface of the sea. This investi- 

 gation had a practical bearing in explaining the natural manuring, 

 with nitrogen and potash, of land near the sea. This process 

 occurring today must have occurred from the very beginning. 



