THE glaciers of the Alps have lost considerably in bulk during the last forty years. This began at rather different dates, for some were still advancing in 1860, while by 1870 the diminution was very marked. Since then there have been slight oscillations, but until lately loss, on the whole, has exceeded gain; now, perhaps, the tide has turned. The report on the Unter Grindelwald glacier, by Prof. A. Baltzer,1 describes the changes this glacier has undergone during the above-named period, and the results of some special observations made between 1892 and 1897. It was unusually well suited for the purpose, for its changes had been very conspicuous, and they had been already more closely observed than in many other glaciers.