Thus the tides of the viscous globe are to the equilibrium tides of a fluid globe as to unity, and there is a retardation of the time of high tide after the passage of the tide-generator over the meridian. Further, by arguments similar to that applied in the case of elastic tides, it is found that oceanic tides are reduced by the yielding in the proportion of sin to unity, and that there is an apparent acceleration of the time of high water by It appears by numerical calculation that, in order that the oceanic semi-diurnal tide may have a value equal to two thirds of the full amount on a rigid globe, the stiffness of the globe must be about twenty thousand times as great as that of pitch at freezing temperature, when it is hard and brittle. We must here pass by the results of the hypothesis of an elasticity degrading under the influence of continued stress.


Footnote

374-6 G. H. Darwin, Phil. Trans., pt. i., 1879, p. 1; see also Lamb, "On the Oscilliations of a Viscous Spheroid," Proc. Lond. Math. Soc., Nov. 1881, p. 51.






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