194 The A7nerican Geologist. September, i8f9 
the Mediterranean, but as these waters do not show this change, we 
conclude that Bourdalone is right; the mean level of the Red sea is 
beyond dispute somewhat in excess of 21X feet above that of the Medi- 
terranean. 
Now then, if we can place confidence in Ferrel's computation, these 
ocean currents must necessarily elevate the sea level wherever they im- 
pinge on a coast line, and depress the same wherever they flow away 
from a coast' line. I have also shown that these elevations and de- 
pressions have actual existence, and that the observed deformations 
of the sea level agree with the mathematical demands of Ferrel's table, 
so far as our knowledge of the velocity of flow will enable us to judge. 
Does it not follow, then, if from any climatic or other cause the 
gulf stream, for instance, should decrease slightly in its flow, that there 
should be a fall of sea level on all those coasts where the deformations 
had been plus, and a rising of sea level on those shores where the de- 
formations had been minus? In other words, if these ocean currents 
should decrease in their velocity of flow, Scandinavia, Spitzbergen, 
Bab-el-Mandeb, arctic Russia, Alaska and Texas would immediately 
enter upon an epoch of apparent upheavel, while New Jersey, New 
York and the American coast generally, from North Carolina to 
Greenland, should enter upon an epoch of subsidence. 
Now we know that these theoretical upheavals and depressions, 
exactly as our assumption demands, are a matter of record; we might 
be allowed to infer therefore that these contemporaneous changes in 
the sea level, up here, down there, precisely according to law, are, when 
properly interpreted, merely proof almost incontestable, that when M. 
Babinct said "We may boldly aflirm that the current passing around 
North cape is lessening" (Smithsonian Rep., 1869, page 291) he was 
making a statement which seems now to be supported by testimony of 
a more satisfactory nature than that on which he based his original 
conclusion. 
My contention is then, that when men of science, without excep- 
tion, have attributed these changes in sea level, to the upheaval or de- 
pression of the solid earth, there is a strong probability that they 
were in error, and that Huxley's dictum, — "It is therefore absurd to 
assume a rise (of the sea level) in one place and a fall in another at 
the same time" (Physiography, page 211) is not well founded, and is 
opposed to the principles of hydro-mechanics. 
In explaining these so-called upheavals and depressions by a mo- 
tion of the earth's crust, we can understand, even if we do not accept, 
the contention of geologists, that contraction by cooling will cause 
this upheaval, but neither we nor they can understand how this cool- 
ing will produce the subsidence; they therefore, to explain this latter 
phenomenon, appeal to the unknown and the supernatural. Some 
philosopher has said "exhaust all known processes before appealing to 
the unknown, in explanation of observed facts." 
In these ocean currents, there is a known cause for all these here- 
tofore unexplainable occurrences; the difference in level. Jjetween the 
North pole and the Mediterranean, is easy to explain on "mechanical 
