AKNIVEKSARY ADDRESS OF THE PRESIDENT. 65 



E-uwenzori, together with an island, or more than one, containing 

 part of the Abyssinian tableland, which, like the others, would be 

 entirely composed of volcanic rocks, but, unlike them, would consist 

 of horizontal or nearly horizontal lava-flows, probably of JVIesozoic 

 age. In Southern Africa, too, the peaks of the Stormberg and Dra- 

 kensberg, though not rising or scarcely rising above 10,000 feet, are 

 the highest in the country and consist of volcanic rocks. The same 

 is the case with the highest peaks in Madagascar, in Mexico, iu the 

 Caucasus, in the Elburz Chain south of the Caspian, and in many 

 other parts of the world ; though the case of Africa is perhaps the 

 most remarkable. 



III. The Absence of Deep-sea Duposits in Continental Areas. — This 

 argument is, I think, of far greater importance than either of the 

 preceding. It is perfectly true that the presence or absence of deep- 

 sea deposits in continental areas is only indirectly connected with the 

 condition of the present oceanic areas in past times ; because, even 

 if no change whatever has taken place in the former, that does not 

 prove that none has taken place in the latter. Even if no part of the 

 continental area has ever been deep sea, anj' oceanic area may have 

 been land at one time or another, the necessary compensation having 

 been provided by the deepening of another oceanic tract. But 

 there can be no question that, unless the amount of ocean water 

 on the earth's surface has greatly increased in the later geological 

 epochs, there must have been deep sea over a considerable portion 

 of the earth's surface at all times ; and if the continental areas have 

 remained unchanged, the oceanic areas have, in all probability, pre- 

 served their original limits. The question for us at present is, 

 whether we have sufflcient evidence to justify our belief that the 

 continental areas have remained unchanged. 



In this case, even more than in that of the oceanic islands, it 

 appears premature to conclude that our knowledge approaches com- 

 pletion. Because in the extremely small area of the land surface, 

 assuredly not one-twentieth of the whole, that has received close 

 geological examination, no deep-sea deposits have been observed, we 

 have no right to assume that none will ever be discovered in any 

 part of the continental area. The recognition of the character of 

 deep-sea deposits is too recent for geologists in general to have 

 become acquainted with the peculiarities of such formations, so as 

 to be able to recognize them at once. On the other hand if deep- 

 sea deposits were not of exceptional occurrence on continental areas, 

 some would probably have been noticed before this. It has I believe 



