which he was familiar in Norway, and likewise great masses of detritus, including grooved pebbles. Along this whole space of the Cordillera true glaciers do not now exist even at much more considerable heights.

Further south, on both sides of the continent, from latitude 41 degrees to the southernmost extremity, we have the clearest evidence of former glacial action, in numerous immense boulders transported far from their parent source.

From these several facts, namely, from the glacial action having extended all round the northern and southern hemispheres — from the period having been in a geological sense recent in both hemispheres — from its having lasted in both during a great length of time, as may be inferred from the amount of work effected — and lastly, from