J. D. Dana— Results of the Earth’s Contraction, etc. 423 
Art. XLVI.—On some Results of the Earth's Contraction from 
cooling, including a discussion of the Origin of gies and 
e nature of the Earth's Interior; by JAMES D. Dan 
Parr L 
PREPARATORY to a discussion of some questions peat 
with the earth’s contraction, I here present a statement o f f the 
is given to earlier writers in connection with the articles referred 
to. The views are as follows :+— 
1. The defining of the continental and oceanic areas began with 
the commencement of the earth’s solidification at surface, as 
and rendered souipanitive! ielding, the oceanic part went 
on cooling, solidifying, and catteaeting throu hout ; consequently 
it became de epressed, be the sides of the epression somewhat 
abrupt. The formation of the oceanic basins and continental areas 
was thus due to “ ise a radial contraction.” o 
* Volume ii, 385; iii, 94, 176, 380: iv, 88; xxii, 305, 3 
+ I may add in this place that a sight of Madler’s chart oe Moon in 1846, six . 
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¢ The principle thu y Prof. ; 
(1872,) does not differ essentially from my old view. except that it is connected with 
the idea of a solid glo obe. — — on p. 466 of his article, attributes to me 
the opinion that the “ sinking sea bottoms, determined by interior con ion, 
18 _ wl. greg of the] force “s — continents are elevated.” But I have never 
referred the origin of continents to such a cause, or to any other than that stated 
=. 
reover, the weet amine of roto on the borders of continents I have at- 
. Inv 
occur “near the limit between the great con ing non- 
y : 
