THE DEPTHS OF THE SEA 



IK 



PAST EPOCHS 



BY 



E. B. VVETHERED, F.G.S. 



At the beginning of this century Hutton taught tliat the 

 past history of our planet is to be explained by what we 

 see going on at the present time. The lapse of more than 

 half-a-century has proved the truth of this assertion. 



Applying this principle to the Depths of the Sea we 

 have been at a disadvantage. Up to the time of the 

 "Challenger" expedition our knowledge of what was to be 

 found was very limited, and we knew less of those regions 

 in past epochs. 



We now know that at the present time calcareous 

 deposits are taking place over very extensive areas, and 

 that these are largely the result of the accumulation of the 

 tests and skeletons of microscopic life. The Globigerina 

 Ooze is an instance of this. We have, too, proof that 

 larger creatures, moUusca, corals, etc., contribute in 

 the same way to the building up of calcareous deposits, 

 l)Ut this appears to be the case chiefly in shallower waters. 



Modern dredging a})pliances have made it comparatively 

 easy to obtain this information from the depths of the 

 ocean of to-day, but how are we to know what took })lace in 

 past epochs ? It is possible that in the case of extreme 

 de])ths we may always remain in ignorance, but of the 

 shallower waters we may obtain very considerable 



