618 
Daty'); it has been especially brought to the fore by Warner’) 
and is also accepted by AnprEw*) and Dacevk*). 
From it follows that the continents must be considered as flows 
of salie composition, floating in the sima in the same way as ice- 
bergs do in water, being submerged’) with about 95°/, of their mass. 
Moreover the very fact of the existence of isostasy everywhere 
on earth, as proved by the observations and considerations of Hecker, 
HerMmerT and Hayrorp, leads to the conclusion that the sal as well 
as the sima, as soon as the masses are considerable, behave under 
the influence of gravity like bodies with some degree of plasticity ®) 
and that this plasticity is somewhat more developed in the sima 
than in the tougher sal. It is exactly through this plasticity, however 
small it may be, that isostasy is maintained and that notwith- 
standing various geological factors which continually disturb the 
isostatic equilibrium the isostatic compensation is even at the present 
day still fairly well complete in most places on earth. 
Smaller masses, however, are often not compensated. The Olympus 
mountain range e.g. in the state of Washington shows a fairly great 
positive anomaly of the value g, i.e. of gravity. Now this range 
stands upon and in the salic block of the American continent, which 
has sufficient rigidity to bear and support this isostatically non- 
compensated body. It may be assumed that isostatically non-compen- 
sated nuclei on or in the continental blocks can remain very long 
in a condition of apparent stability. 
The matter is quite different, however, for true oceanic islands, 
Le. islands whose base is not connected with any continental block. 
Such islands rise directly from the ocean-bed and have never formed 
part of any continent. 
1) R. A. Dary. Igneous rocks and their origin, 1914, p. 164. 
*) A. WEGENER. Die Entstehung der Continente und Oceane, p. 19. Braunschweig 
1915. WEGENER on pp. 15—19 pleads convincingly in favour of this view. 
WEGENER had already published the main outlines of his hypothesis in the 
Geologische Rundschau Ill, 1912, p. 276. 
5) K. AnprÉe. Ueber die Bedingungen der Gebirgsbildung, p. 32, Berlin 1914. 
+) E. DacquÉ. Grundlagen und Methoden der Palaeographie, p. 96, Jena 1915. 
5) This simile has also been used by PrekerinG and later again by WEGENER 
ee: pes: 
6) CHAMBERLIN compares the plastic yielding and consequent lateral horizontal 
outward flow of the continental masses (“outward creep of the continents”) under 
the influence of gravity so far as the character of the movement is concerned, 
with the behaviour of glacier-ice under the same influence. 
T. CG. CHAMBERLIN. Diastrophism and the formative processes IL. Journal of 
Geology. Vol. XXI, p. 577 -- 587, 1913. 
