The age of the Earth

Primitive races and their creation myths—The chronologies of Eastern sages—The demands of geology opposed by theological prejudice—Bishop Ussher’s date of the creation of the wo...

Early ideas of cosmogony—The Laplacian hypothesis—Tidal friction in the earth-moon system—Its application by Kelvin to the question of the earth’s antiquity—Its application by S...

The Great Ice Age—Extension of glaciation—Croll’s ingenious hypothesis—Inadequacy of the explanation—The ice caps of Mars—De Geer’s discovery of the annual layers of glacial cla...

Transference of material from land to sea—The denudation ratio—Weathering of rocks—The work of chemical denudation—Summary of the data—Composition of the saline matter in the oc...

Halley’s proposal in 1715—Joly’s application of modern data in 1899—Further studies by Sollas, Clarke, and Becker—Data of the problem—Corrections for disseminated sodium, wind-b...

The maximum thickness of the sedimentary rocks—Rate of deposit—Uniformitarian basis of the method as usually applied—Arguments against the validity of this assumption—Present a...

Geological application—Röntgen rays—Becquerel rays—Mme. Curie and the discovery of Radium—The gold-leaf electroscope—The nature of α-, β- and γ-rays—Helium and its production fr...

The sun’s heat and the conservation of energy—Mayer’s meteoric hypothesis—Helmholtz and contraction under gravity—The earth’s dependency upon solar radiation—The work of Kelvin...

Temperature gradients, conductivity, and the rate at which the earth loses energy—Kelvin’s attempt to estimate the age of the earth—King’s treatment of the problem—Estimates by...

The rate of helium production from uranium and thorium—Lead the final product of the uranium family—Its accumulation in geological time—Lead and helium ratios as a measure of ge...

The discrepancy between the geological and radioactive methods of estimating time—Uniformity of the rate of decay of uranium—Joly’s criticism—Comparison of the two time-scales—D...

Thomson (Kelvin). _Rep. Brit. Ass._, p. 1819. 1855. —— _Proc. Glasgow Phil. Soc._, Vol. IV, p. 272. 1860. —— _Phil. Mag._, February, 1862, p. 158. 1861. —— _Popular Lectures and...

Chamberlin and Salisbury. _Geology_, Vol. II, Chaps. I and II. 1909. T. C. Chamberlin and other Writers. _The Tidal Problem._ Carnegie Inst. of Washington. Pub. No. 107. 1909. D...

Croll. _Phil. Mag._ May, 1868. —— _Climate and Time._ 1875. De Geer. _Geol. Fören i Stockholm Föhr Band 32._ 1910. Gilbert. _Journ. of Geol._, Vol. III, p. 121. 1895. Lowell. _E...

Babb. _Science_, Vol. XXI, p. 343. 1893. Clarke. _Data of Geo. Chemistry. Geol. Sur., U.S.A. Bull. 491._ —— _Smith. Misc. Collect._, Vol. LVI, No. 5. 1910. Dittmar. _Challenger_...

Ackroyd. _Chem. News_, p. 265. 1901. —— _Geol. Mag._, p. 445 and p. 558. 1901. Becker. _Science_, Vol. XXXI, p. 459. 1910. —— _Smith. Misc. Collect._, Vol. LVI, No. 6. 1910. Cla...

Blake. _Geol. Mag._, p. 72. 1903. Croll. _Stellar Evolution_, p. 48. 1889. Geikie. _Rep. Brit. Ass._ 1892. —— _Nature._ August 4th, 1892. —— _Rep. Brit. Ass._, p. 727. 1899. Hau...

Mme. Curie. _Traité de Radioactivité._ 1910. Ramsay and Soddy. _Proc. Roy. Soc. A._, Vol. LXXII, p. 204. 1903. Russell. _Proc. Roy. Soc. A._, Vol. LXXXVI, p. 240. 1912. Rutherfo...

Buchner. _Proc. Konink. Akad. van Wetensch. te Amsterdam._ October, 1910, February, 1911, and April, 1912. Chamberlin. _Journ. Geol._, p. 674. 1911. Eve and McIntosh. _Phil. Mag...

Becker. _Bull. Geol. Soc., Am._, Vol. XIX, p. 113. 1908. Boltwood. _Am. Journ. Science_, p. 260. 1905. —— _Am. Journ. Science_, Vol. XXIII, p. 77. 1907. Boltwood and Rutherford....