Drift Period

the period during which the drift described above was deposited. ‘Though there is no reason why it should not have recurred time after time during bygone geological ages, and perhaps it may be ultimately proved cpeaiaenaly that it has done 80, yet the term “ drift-period” as a measure of duration is limited to the time commencing during the Newer Pliocene or Pleistocene, and terminating with the Post Pliocene or Post Pleistocene, during which drift was deposited in the latitudes in which we find it now. The drift is now universally attributed, as Aga iz long ago suggested, to the action of ice, the only controversy remaining being whether land ice or floating icebergs took the chief part in its distribution.