8 BULLETIN OF THE NATURAL HISTORY SOCIETY. 



The Abyssal Channels op the Ocean. 



The prime cause of climatic differences, for the earlier 

 ages of geological time, is to be sought in the action of the 

 sun's heat on the surface of the globe ; and can be traced by 

 its influence on marine organisms, because we know of no land 

 animals or plants in the earliest ages. 



The explorations of the Challenger and other vessels 

 sent out to measure and explore the depths of the sea, 

 have shown that there are enormous areas of the ocean where 

 the depth is from 2,000 to 4,000 fathoms. If we estimate 

 the average level of the land surfaces at 1,000 feet, as Dana 

 has done, and bear in mind that the surface area of the land 

 is only a third of that of the sea, it will be clear that if this 

 land were flung into the ocean it would go but a short way to 

 filling it up. The sea, in fact, would roll above it two thousand 

 fathoms deep. 



We are told that there was a time when the "earth was 

 without form and void,'' and in view of the apparently 

 artificial or unnatural way in which the continents are 

 bolstered up, it seems not unreasonable to suppose that there 

 has been a time when all these lands were buried beneath the 

 ocean, and that the earth was actually thus formless. But 

 in the earliest times of which we have any knowledge through 

 geological evidences, some portions of the land was above 

 the sea, and continental or emerged areas existed. How, 

 then, were those lands sustained above the ocean? What was 

 this mysterious power which for uncounted ages kept these 

 lands with more or less completeness above the sea, or at 

 least above the deep abysses of the ocean. The rains, the 

 frosts, the winds and the transporting power of rivers have 

 been ceaselessly at work through uncounted ages levelling 

 down these continents, but have not destroyed them. There 

 must be something in the physical constitution of the globe 

 itself which maintains them. The abysses in the ocean 

 themselves offer the explanation of the phenomenon, for they 

 have been found to be the channels by which frigid waters 



