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BATHYBIA. history and physical data so far experienced in Bathybia, was instituted. Summarising the various points brought forward as bearing on a scientific elucidation of the phenomina observed, the following are worthy of note.

Bathybia was a great depression some hundreds of miles across, bound on the East by a great fault face, but with more gently rising boundaries in other directions. In fact it might be likened to a portion, for example, of the basin of the Pacific Ocean from which the water had been removed.

It seemed to us almost certain, that the folding and faulting of the earth giving place to this configuration, must have taken place at a period corresponding to a maximum phase of a great ice age, when the Antarctic regions supported an ice cap of stupendous thickness. The ice must then have played the rôle of rock, when the great earth movement referred to occurred.

At a later date, as the ice age passed away, ablation, removing the ice strata, exposed the deep basin of Bathybia. The lower portions of this basin, situated below so great a thickness of atmosphere, was blanketed from the great cold of the upper regions.

To this end also, the humidity and increased abundance of carbon-dioxide in the atmosphere aided.