Penny Blood: Serial Sensation and Working-Class Entertainment — page 310: what you’re looking at

Machine-transcribed from the original scan — historical spelling and the odd misread are preserved.

APPENDIX. 293 “Tn any ‘case, the contraction due to the cooling of the globe ought to introduce a progressive acceleration of its angular velocity. But, if this globe is fluid, the form of the different layers adapt themselves continually to the rotation such as it is at every instant, so that, finally, there remains no more trace of the successive changes which their ellipticity has undergone since the beginning. If on the contrary at a certain epoch of the cooling, the interior layers have passed into the solid state, these layers have taken and retain an ellipticity very different from that which the general hydrostatical equation would at- tribute to them, applied to a mass entirely fluid possessing a rotation common to all its parts. The formule calculated on the hypothesis of the solid nucleus contain at once the constant q, the actual ratio of the centrifugal force to gravity at the equator, and the value g, of the same ratio at the epoch of the solidification of the central block. This last element not being determined, we may give it a value such that the superficial ellipticity agrees with the coefficient of the precession. It is necessary, for this, to suppose q, less than g, whence it results that the rotation of the earth has undergone an acceleration since the consolidation of the interior nucleus.” “The physical and astronomical conditions of the problem allow us moreover to determine with sufficient precision the dimensions and the specific weight of this block. If we neglect the purely superficial shell, as well as a slight condensation towards the centre, where the heaviest materials must be col- lected, observe what will be the constitution of the globe: a nucleus of which the density is about 7, covered with a layer of density 3, of which the thickness will not attain {th of the entire radius.” “The terrestrial block is then as regards the specific weight, analogous to meteoric irons, whilst the layer which envelopes: it is comparable to the aerolites of a stony nature, into which iron enters only in small proportion.” It need hardly be said, that the results obtained by M. Roche are such as most Geologists would be ready to accept. Until the memoir appears in full, it 1s not possible to form a @ NOO (CO) COU