GEOLOGY. 



No. 106. CHAMBERLIN, R. T. Contributions to Cosmogony and the Fundamental 

 Problems of Geology, Gases in Rocks. Octavo, 80 pages. Published 

 1908. Price $0.50. 



A study of gases in rocks to determine their range and distribution, the states 

 in which gases or gas-producing substances exist in rock, with deduction as to the 

 general relations of the gases relative to the hypothesis of a molten earth, also 

 relative to the planetesimal hypothesis and to atmospheric supply. 



No. 107. CHAMBERLIN, T. C., et al. Contributions to Cosmogony and the Fun- 

 damental Problems of Geology. The Tidal and Other Problems. 

 Octavo, iv+264 pages, 19 cext figures. Published 1909. Price $1.50. 



This book contains the following papers, not sold separately: 



1. The Tidal Problem: 



CHAMBERLIN, T. C. The Former Rates of the Earth's Rotation and their Bearings 



on its Deformation. 



SLIGHTER, CHARLES S. The Rotation Period of a Heterogeneous Spheroid. 

 MACMILLAN, WILLIAM D. On the Loss of Energy by Friction of the Tides. 

 MOULTON, F. R. On Certain Relations among the Possible Changes in the 

 Motions of Mutually Attracting Spheres when disturbed by Tidal Interactions. 

 MOULTON, F. R. On the Possibility of Fission of a Contracting Rotating 



Fluid Mass. 

 CHAMBERLIN, T. C. The Bearing of Molecular Activity on Spontaneous Fission 



in Gaseous Spheroids. 



II. LUNN, ARTHUR C. Geophysical Theory under the Planetesimal Hypothesis. 

 III. STIEGLITZ, JULIUS. Relations of Equilibrium between the Carbon Dioxide of the 

 Atmosphere and the Calcium Sulphate, Calcium Carbonate, and Calcium Bicar- 

 bonate of Water Solutions in Contact with it. 



Professor Chamberlin's paper contains a treatment of the effects of the earth's 

 tides based upon (a) hypotheses as to the origin of the earth; (&) deductions from 

 the tides themselves; and (c) geological evidences of tidal friction. The conclu- 

 sions reached are that the tides of the lithosphere, hydrosphere, and atmosphere 

 at present are not sensibly changing the rate of the earth's rotation, and that the 

 geological evidences indicate that during geological history the rate of rotation of 

 the earth and its shape have been approximately as they are at present. 



Professor Slichter gives, in tabular form, the polar and equatorial radii, the ellip- 

 ticity, the polar and equatorial attractions, the latitude of mean radius, the equa- 

 torial contraction, and the meridional elongation for various rates of rotation. 



The rate of change of rotation of the earth from the rate of degradation of 

 energy in the ocean tides is computed by Professor MacMillan. The result reached, 

 after making liberal assumptions as to the magnitudes of the tides, is that they 

 lengthen the day one second in 500,000 years. 



The first paper of Professor Moulton starts with the present earth-moon system 

 and, by considering particularly the relations of energy and moment of momentum, 

 traces the members of the system back to their closest possible proximity. It is 

 found that at their closest possible approach their surfaces were more than 4,000 

 miles apart, and it is inferred that the moon did not originate by fission from the 

 earth. From a consideration of the secular acceleration of the moon's motion it is 

 found that the day is now changing at the rate of one second in 13,000,000 years. 



Professor Moulton's second paper starts with the original united hypothetical 

 earth-moon mass and considers the question of its fission. It is found that the 

 mass could not suffer fission under contraction until its density became many times 

 that at present. This paper, together with his preceding paper, leads to the conclu- 

 sion that the moon has not originated by fission from the earth. 



Professor Chamberlin, in his second paper, considers the bearing of molecular 

 activity on mass fission, and concludes that it keeps the equilibrium from becoming 

 disturbed to such an extent that the separation of large masses is possible. 



Professor Lunn's work is mainly a quantitative study of that portion of the 

 earth's internal energy which may have been derived from the mechanical energy 



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