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Rh class; and the differences between rural and urban laborers to differences of housing and sanitary surroundings; for both classes probably suffer about equally from poverty, hard work, and hard living. The great reduction in the rate of mortality among the inhabitants of the Peabody buildings, as compared with other tenement-house dwellers, points to one method of bringing the mortality of the working-classes within sanitary control. These and other similar facts indicate further reductions in the now rapidly declining English death-rate, the possible extent of which it is not easy to estimate.

Glaciation on the Pacific Coast.—Mr. G. Frederick Wright has, in the "American Naturalist," some notes on the "Glaciation of the Pacific Coast in Oregon and Washington Territory." At Sims's Station, Dakota, forty miles west of Bismarck, the passage from the glaciated to the unglaciated region is quite marked, and can easily be detected from the train. The next signs of glaciation are near Lake Pend Oreille, in Idaho, water-worn pebbles from whence are observed in old water-courses far down in Eastern Washington Territory. West of the Cascade Mountains, all the streams coming down from Mount Rainier and its companions are heavily charged with glacial mud, and can be traced to extensive glaciers in the mountains. The largest of them, White River glacier, on the north side, is from one to one and a half mile wide at its termination at about five thousand feet above tide, is about ten miles long, and in its higher level merges in the general ice-cap which envelops the upper five thousand feet of the mountain. The shores and islands of Puget Sound have every appearance of being a true glacial accumulation, while the north shore of the Strait of Juan de Fuca, near Victoria on Vancouver's Island, is remarkably clear of glacial débris; the rocks near Victoria exhibit some of the most remarkable effects of glacial scoring and striation anywhere to be found. About thirty-five miles up the Stikine River, two glaciers of immense size are encountered coming down, one from the north and one from the south, to the vicinity of the vast canon through which the river runs. It is clear from observation of the situation that a comparatively slight extension of these two glaciers would make them unite and close up the mouth of the river; and the Indians have a tradition that within historic times these glaciers met and the Stikine River made its way under them through an immense tunnel. From the mouth of the Stikine River northward, glaciers in great numbers and of great size are seen coming down from the mountains toward the sea-level, while all the mountains upon the islands are snow-clad through the whole summer, and some of them contain glaciers of small size. At the head of Glacier Bay no less than four glaciers of great size come down to tide-level, sending off immense numbers of small fragments and bergs. The evidence here of the vast extension of these glaciers down the bay, and of the facility of glacier-ice in adjusting itself to the local topography, is of the most explicit and interesting character. The present formation of glaciers on the coast of Southwestern Alaska is favored not so much by the coolness of the climate as by the elevation of the mountains, and the excessive amount of precipitation. There is no evidence that the elevation of the coast has materially changed in recent times. Nor is there evidence of any changes in the amount of precipitation. It would only be necessary to suppose a slight diminution of temperature to secure all the additional force required to extend the present glaciers of Southeastern Alaska, British Columbia, and of the Cascade Range in Washington Territory and Oregon, far down into the South, where the marks of former glacial action are now seen.

The Use of a Snake's Rattle.—The purpose of the rattlesnake's rattle has been the subject of much speculation. Mr. O. P. Hay, in the "American Naturalist," thinks that it is a warning to approaching enemies to keep them away. The warning must have been very efficient with most animals. The snakes are, of course, in great danger of being trodden upon by animals which do not intend directly to attack them—buffaloes, for instance—and to attempt war on a herd of large animals would be useless. But through the simple device of sounding the rattle, each animal as it approached would