T. Mellard Reade—Oceans and Continents. 389 
extent of from 1400 to 2000 feet.'!. There is therefore no improbability 
in the sea-floor being raised to the extent even of five miles. 
To say that no continent averages more than, say, 1200 feet above 
the sea-level, is no answer to this, as no doubt there must exist some 
general balance of stability of deformation in the globe. The reason 
the surface of the land ranges so little above the level of the sea points 
to the likelihood of any greater height being “unstable”; that the 
foundations of the earth would not bear any greater irregularity in 
the distribution of weight? It must be kept constantly in mind 
also, that if the crust of the earth is mobile, the elevation of a mass 
of land of large superficial extension through water would require 
between 4 and 4 less effort than through air, therefore the “stress ” 
_ the foundations would be to that extent (the weight of the water) 
ess. 
If the continents are the portions of the earth that have first 
hardened, it is strange that it is just these hardened bosses that have 
to be most unstable, according to the further requirements of the 
theory, and the most subject to voleanic action. Nor is it probable 
that so large an area as the Pacific could have existed since the 
beginning of geological history with volcanos in its midst, without 
the growth of something more than the groups of small coral islands 
that now exist there. 
According to the theory, also held by those in favour of the 
fixity of continents and oceans, that volcanic energy is dying out, 
in former times these Pacific volcanos must have been more active 
and numerous, and surely some land would have been built up 
from the bottom had other conditions been stable. But it may 
be alleged, and I believe is, that this has always been a subsiding 
area; that, in fact, independently of minor oscillations, all the deep 
seas are areas of subsidence, and all continents areas of upheaval, 
and have been since the beginning of time. This notion shows a 
strange ignorance of solid geometry or “ fluid” geometry if so be it! 
for if the sea-floor of the Pacific, covering an area of the earth's 
surface nearly equal to that of all the land, has constantly subsided, 
where did the waters of the ocean, the bulk of which can hardly have 
increased, put themselves before the subsidence of the sea-bottom 
was complete or nearly complete? The answer is obvious—they 
1 Mr. Gwyn Jeffreys, F.R.S., in a paper recently read before the Geological 
Society, seems also to have been impressed with the evidences of recent subsidence 
and elevation as an argument in favour of the older views as to continents and oceans. 
2 Professor Judd writes me: ‘‘ Why the mountain masses of the globe rise so 
little above the surface of the ocean I take to be due to the great rapidity of subaerial 
denudation in the higher regions of the atmosphere. The moon, which is a much 
smaller globe than ours, has much more prominent features, If the rate of waste 
gradually increases as we rise higher in the atmosphere (owing to inequality of 
temperature and condensation of moisture, etc.), then the tendency will be to keep 
down all great inequalities. All our mountains, therefore, are comparatively small, 
and all the highest are of recent formation geologically speaking.”’ 
This reasoning I thoroughly agree with as regards mountain masses, but the small 
average elevation of whole continents above the sea-level I think points to the 
possible instability of other conditions, mechanically speaking, and to the probable 
mobility of the crust of the earth as regards large areas, 
