“In 1904, Prof. W. H. Sherzer, on behalf of the Smithsonian Institution of Washington, D.C., visited the Canadian Rockies for the purpose of studying their glaciers. Among a series of five, he made a special study of the Illecillewaet glacier situated about seven and a half miles from the Caves. At some distance from the present ice-tongue of the glacier, were found two moraines about a third of a mile apart, composed of enormous blocks of quartzite, weighing in some single instances as much as 1,250 tons, and retaining the original shape in which they were cast from the peaks above to the snow-field and glacier transporting them to the place where they are now found. Prof. Sherzer has named these ‘Block Moraines’ in distinction to ordinary moraines composed of ice-worn, rounded boulders imbedded in a species of cement, commonly known as boulder clay. “The question is: How and at what time were these block moraines formed. At the present day the glaciers are wholly incapable of transporting such a load, and no such quantities of material are to be found upon the snow-field, below the peaks, as would be necessary to form a similar moraine, even during a protracted period of rest on the part of the glacier. “In the endeavor to ascertain a date for their formation, Prof. Sherzer cut down trees growing between the two moraines and counted the rings of growth. The oldest was found to have an age of 550 years. Trees, also, growing on the inner or younger moraine were measured and the age of the oldest ascertained to be 447 years. Allowing for the time required for the collection of sufficient soil to permit of growth taking place, the moraine, therefore, would be between 500 and 600 years old. “Professor Sherzer points to the probability of seismic disturbances being the cause of these block moraines and that the material of which they are formed had been shaken from the peaks to the snow-field below. Making due allowance for the period of transportation of the material forming the inner moraine, the earthquake would thus have occurred during the thirteenth century. (See ‘Glacial Studies in the Canadian Rockies and Selkirks, Smithsonian Expedition of 1904,’ by William Hittell Sherzer, Ph. D.)