MAJOR EARTH FEATURES 
197 
and sea-basins has at all times been kept within comparatively 
narrow limits/ If we follow the history of the ocean still further 
back, it appears that as early as Cambric time evidences are 
present of the existence of a Pacific as well as of an Atlantic 
and an Indian Ocean. 
In order to reach this conclusion, we must by all means bring 
into use a method of study which in paleogeography as well as in 
geology proceeds mainly from the present relationships, and 
which accepts changes in the present maps only in so far as is 
made necessary by established biographic and geologic in¬ 
vestigations. I believe, moreover, that only the consistent appli¬ 
cation of this method will lead us to the reconstruction of maps 
of the older periods of earth history which, to quote Koken, mean 
more than the geographic expression of the thoughts of an author. 
It will, I expect, make even the European geographers and geol¬ 
ogists who up to this time have as a majority been outspoken 
against the permanence of continents and ocean-basins, more in¬ 
clined to recognize the correctness of that theory which Bailey 
Willis represents, namely, that the permanence of great sea-basins 
stands almost outside the category of questions which are still 
debatable.®^ 
If we concede a permanence of the major forms of the earth’s 
crust, at least in the main — apart of course from the manifold 
changes in the labile mediterranean zones — then there is no 
longer any necessity for the acceptance of horizontal movements 
of salic continental blocks over the Sima of the ocean floors. 
The isostasy between continents and ocean-basins also exists only 
in the main features, not in the individual ones. No geophysical 
argument is opposed to the sinking of individual fragments of the 
continental platforms into the abyssal deeps. The evidence for 
the breaking up of a former continent in very recent times found 
in the geologic structure of the coast lands around the Aegean Sea 
must nullify any speculations to the contrary.®^ 
31 This thesis agrees essentially with that of Dana (Amer. Jour. Sci. (1), Vol. 
XXII, p. 339, 1856), from which the discussion of the permanence problem in his 
time started: “The continents have always been the more elevated land of the crust, 
and the oceanic basins always basins, or the more depressed land.” 
32 The observations made by Philippi on the bottom soundings obtained by the 
“Gauss” from the Romanche deep and from the vicinity of the Walfischriicken, with 
their “reversed” calcareous beds, also testify to local crustal movements on the sea 
bottoms in recent time. 
