and the Outlines of its Bottom. 157 



from the surface ; thus illustrating one of the phenomena on 

 which Mr C. Darwin has thrown so much light. 



In looking at the statement of Captain Denham, and at the 

 vast number of desiderata that remain to be inquired into, it 

 is not, therefore, too much to affirm, that until our submarine 

 knowledge shall have been vastly more extended than it is ; 

 until, in short, we know as much of the earth beneath the 

 waters as of that which is above them, we are wanting in 

 several of the most essential elements to explain the proxi- 

 mate causes of the deflection of the great oceanic currents to 

 which we have been adverting, as well as of the origin of 

 many climatal peculiarities. 



The geologist, meteorologist, and geographer, are indeed 

 each of them equally interested in the determination of grand 

 problems like these, which will teach us the forms of the 

 submerged lands around which run the various streams deli- 

 neated in the maps of Mr Findlay : such, for example, as 

 that which, with its superjacent floating masses of " Sar- 

 gasso," or sea-weed, circles in the North Atlantic, or the 

 great whaling grounds of the North Pacific, around which 

 the North Equatorial and Japanese currents flow ; or, again, 

 that mass between New Zealand and Australia which is en- 

 circled by the Australian current. 



In this last instance the geologist again steps in to help to 

 solve the problem. The discovery of the enormous bird, the 

 Dinornis, in the comparatively small tract of New Zealand, 

 has naturally led him to suppose that there was once a much 

 larger adjacent mass of land to provide for the sustenance of 

 such huge creatures ; and hence it is a fair inference, that 

 the nucleus around which the Australian current runs, is 

 the central and higher portion of what was a large continent 

 once united with New Zealand.* 



In the meantime, passing from such theoretical views, I 



* The same reasoning may be applied to the island of Madagascar, where 

 eggs of bird3 have been found, which contain the substance of 240 hen eggs. 

 This isle may be the remnant of a former vast Eastern continent now submerged. 

 See Professor Edward Forbes's proofs of the existence of such ancient conti- 

 nents, derived from the present insulation of certain groups of plants and ani- 

 mals. — Memoirs Qeol, Surv., vol. i. 



