OROGENY AND EARTH’S ROTATION 
53 
leading votaries of earth-study, among them Cordier,- De la Beche,^ 
Dana,^ Elie de Beaumont,® Le Conte,® Heim,^ and Suess.® The 
last mentioned writer, Suess,® who so long and so strenuously 
argues for the recognition of the contractional theory, proposes 
so many collateral hypotheses that his entire theory is put in 
jeopardy, and is now challenged in many different w’ays by many 
workers throughout the world. 
Probably the strongest argument against the old secular refrig¬ 
eration theory is that furnished by the recent discovery of radium. 
By it not only are many of our most cherished notions concerning 
the constitution of the earth completely revolutionized but that of a 
cooling globe passes at once into the realm of fiction. Indeed, 
Prof. J. Joly even goes so far as to warn us that if the central 
parts of the globe contain anything near the quantity of this new 
element found near the surface we may even be going in the other 
direction; and instead of a peaceful cooling there may be catas¬ 
trophic heating; and the now inconspicuous little body known as 
Our Earth may sometime become famous through the universe 
as a new star. 
Concerning the shortening of the earth’s crust we may be there¬ 
fore fully justified in first examining seriously every other ex¬ 
planation of orogeny that we know of before we accept that of 
secular refrigeration and a shrinking nucleus. 
That there is apparently a certain amount of contractional force 
involved in the upbuilding of mountains and that it is mainly a 
horizontally directed force is so distinctly an American conception 
that it really merits more than passing notice. The hypothesis 
doubtless owes its original inception to the brothers W. B. and H. 
D. Rogers as a result of their wide familiarity with the Ap¬ 
palachian mountains. It is, however, to the late Prof. J. D. 
Dana that we are indebted for the first clear statement of the 
theory. Both Dana and the late James Hall perceive, as a 
necessary condition of mountain upheaval, a thick accumulation 
• 2 Mem. Acad. Sci., Paris, T. VII, p. 473, 1827. 
3 Geol. Recher. in Theoretical Geol., 1834. 
4 Am. Jour. Sci., (2), Vol. Ill, 1846. 
5 Les Systemes des Montagnes, three vols., Paris, 1852. 
6 Am. Jour. Sci., (3), Vol. IV, p. 480, 1872. 
7 Mech. d. Gebirgsbildung, two volumes, Basel, 1878. 
8 Entstehungen der Alpen, Vien, 1875. 
9 Das Antlitz der Erde, three vols. 
10 Trans. Assoc. American Geol. and Nat., p. 474, 1843. 
11 Am. Jour. Sci., (2), Vol. Ill, p. 94, 1847. 
12 Pal. New York, Vol. Ill, pp. 1-96, 1859. 
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