Recession measurements have been made on the Nisqually Glacier in every year since 1918 and, in addition, the position of its terminus has been located by authentic historical records for three periods, one as far back as 1857 when, in July of that year, Lieut. A. V. Kautz and four companions made the first known attempt to ascend Mount Rainier. This party reached the base of Mount Rainier via the Nisqually Valley. At its upper end they found a wall of ice which was the terminus of the Nisqually Glacier, source of the river of the same name. In his diary of the trip Kautz stated:
This place was identified about 760 feet below the present bridge across the Nisqually River when annual recession measurements were initiated in 1918. In 1835, according to Len Longmire, the ice terminated at a point about where the present bridge spans the Nisqually River. In 1892 the snout occupied a position about 140 feet above the bridge. Since 1918 measurements have been made annually from rocks, appropriately marked, in the river channel. In this manner, with the exception of two occasions hereinafter described, recession data have been computed without difficulty. On October 13, 1932, following a period of exceptionally heavy rainfall, a washout occurred which temporarily modified the appearance of the terminus of the Nisqually Glacier and removed a considerable number of the rocks from the river channel that had served as markers in previous years. However a sufficient number remained intact so that this did not interfere a great deal with the accuracy of annual recession tabulations. This washout was in the nature of a huge "surge" of impounded water which swept off the moraine-covered surface of the glacier, carrying all in its path before it. The concrete bridge, over one quarter of a mile below, was completely destroyed.
On October 23-26, 1934, a similar happening took place. In this case three "surges" materially damaged the new concrete bridge, which had just been completed, and the appearance of the terminus of the glacier was also greatly modified. The marker, which had just been painted on a large rock in the river channel, was destroyed. It was therefore necessary, on November 2, 1934, to establish a new point (310 feet from the ice) on a large granite block for future reference.
Tabulation of recession data.
The average recession of the Nisqually Glacier, since 1857, is 44.35 feet per year. However, if one studies the above tabulation it will become apparent that this glacier, since 1918, has retreated much more rapidly than was the case during, any previous period of years since 1857. From 1857 to 1885 the average annual recession was 27.14 feet. From 1885 to 1892 the average annual recession was 20 feet. From 1892 to 1918 the average annual recession was 50.38 feet while since 1918 the average annual recession has been 70.42 feet.
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(1) See Meany, E. S. Mt. Rainier - A Record of Exploration. 1916. pp. 72-93.
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