In casting about for a subject upon which to address you this evening, I thought I could hardly do better than give you the result of a comparison which I have recently been able to make between the glacial phenomena of Europe and North America. The subject of glaciation seems to be now somewhat worn; but I gather from the fact that writers can still be found who see in our superficial deposits strong evidence of the Deluge, that a short outline of what we really do know may not be unacceptable. In the short time at our disposal, it is obvious that I cannot enter into much detail, and that many interesting questions must remain untouched. It will be as well, therefore, that I should at the outset define the limits of the present inquiry, and state clearly what are the chief points to which I wish to direct your attention. My main object, then, will be to bring into prominence such evidence as seems to betoken in a special manner the uniformity of conditions that obtained in the northern hemisphere during the Ice Age. In other words, I shall confine myself to a description of certain characteristic and representative phenomena which are common to Europe and North America, with the view of showing that the physical conditions of the glacial period were practically the same in both continents. The phenomena which might be considered under this head embrace nearly all the facts with which glacialists are familiar, but I purpose restricting myself to three questions only, viz.:-- 1st. _The extent of glaciation._ 2nd. _Changes of climate during the Ice Age._ 3rd. _The results of fluvio-glacial action._ The consideration of these questions, even if it were exhaustive (which it cannot be on this occasion), would still leave the general subject very incomplete, for we must forego the discussion of all such interesting topics as the "connection between glaciation and submergence," "the formation of rock-basins," and the "origin of the geographical distribution of our faunas and floras." Confining my inquiry within the limits just specified, I shall begin by sketching broadly the general results obtained by glacialists in Europe, and thereafter I shall proceed to give an outline of the corresponding conclusions arrived at by American observers. I. _The Extent of Glaciation in Europe._ To what extent, then, let us ask, has Europe been glaciated? What areas have been covered with perennial snow and ice? Owing to the fulness and clearness of the evidence, we are able to give a very definite answer to this question. It is hardly too much to say that we are as well acquainted with the distribution of glacier-ice in Europe during the Ice Age as we are with that of existing snow-fields and glaciers.