GEOLOGY — CHAMBERUN. I7I 



Paper VII. — Ott the Principal Constants of a7i Earth-like Body tinder the Varying 

 Conditions of Changing Rates of Rotation. By C. S. Slighter. 



A series of ten rotational stages, ranging from a rotation period of 3.82 

 hours to the present rate, is made the basis of computation, the results of 

 which constitute the body of the paper. The constants are worked out 

 on the assumption that the internal densities follow Laplace's law. The 

 methods of computation, so far as new, are given. The data of this paper 

 enter fundamentally into the preceding discussion on rotation. 



Paper VIII. — On Certain Problems of the Hydrosphere and Atmosphere. 

 By T. C. Chamberlin. 



This paper proceeds on the assumption that the climatic problems of the 

 earth center about the discovery and elucidation of a S5'stem of automatic 

 control of such efficiency as to have kept the temperature of a large portion 

 of the surface of the earth throughout its organic history within the narrow 

 range of 100° C, and at the same time to have kept the constitution of the 

 atmosphere within the like narrow range consistent with plant and animal 

 life. The paper recurs to the four-fold organization of a typical atmos- 

 phere set forth in Paper I, and endeavors to apply the states of equilibrium 

 deduced therefrom to the feeding and depletion of the atmosphere. It is 

 recognized that the hj^drosphere is a derivative from the atmosphere, and 

 that its relations of equilibrium with the atmosphere are important factors. 

 The relations of equilibrium between the free atmospheric gases and those 

 absorbed or held in feeble combination in the ocean are considered, together 

 with the conditions and rate of exchange. The discussion of changes in 

 the basis of equilibrium forms a vital factor. The function of the ocean as 

 a source of atmospheric storage and supply is discussed and a possible 

 reversal of the deep-sea circulation, alternating with circulation of the 

 present order, is considered as a possible explanation of the alternation of 

 warm polar temperatures with periods of marked glaciation and aridity. 

 The sources of internal supply of atmospheric and hydrospheric material are 

 reviewed and correlated with sources of depletion, so far as practicable. The 

 function of deformation and base-leveling in changing the available amounts 

 of the critical atmospheric constituents is set forth. The relationship of the 

 atmosphere's constituents to thermal absorption, retention, and radiation, 

 and the bearing of these upon the climate, are also treated. 



Paper IX. — On the Relations of Equilibrium betiueen the Carbon Dioxide of the Atmos- 

 phere a7id Calcium Sulphate and Calcium Carbonate and Bicarbonate in Solutions 

 tft Water in Contact with it. By J. Stieglitz. 



This paper embraces the results of a computation of the varying equilibria 

 subsisting between different degrees of concentration of carbon dioxide in the 

 atmosphere and varying degrees of concentration of calcium carbonate and 

 bicarbonate, and calcium sulphate in solutions in free contact with the atmos- 



