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mapped by Messrs. G. K. Gilbert, Henry Gannett and the Harriman Expedition, it had retreated one or two hundred feet more. Between 1899 and 1905, when the Hubbard Glacier was studied by Professor E. S. Tarr and the writer, the northwest side seemed to have advanced slightly and the southeast to have retreated. That is, although continually advancing strongly, the glacier had extended its ice cliff farther into the fiord only about a quarter mile between 1891 and 1905, because ice was continually being discharged from the end in icebergs. Professor Tarr found very little change between 1905 and 1906, the west half having possibly advanced slightly. It was about the same on this west side in 1909 (Fig. 10).

In September, 1899, however, this glacier, with the others in the region, was involved in an abnormal sort of experience which has notably affected its later history. This was a series of severe earthquakes.

Just east of the cliff of dirty ice shown in the photographs at the right of Hubbard Glacier (Fig. 11) there is a stagnant ice area which