As to glaciological observations upon. the unusual glaciers of this el yet neatly- tropical e a start only has so far been appear to ut their mass, a physical condition "which places them in the category "high polar' glaciers (Ahlmann).
condition would seem to give to a greater brittleness and a tendency, as in the polar regions, for move more by frac-jure and shear than by what approximates to viscous flow. Not more than measures of the speed of these (glaciers have as yet been made.
Another point of interest is that the steeply-inclined solar rays and in-insolation, together with a high ate of evaporation consequent upon the great altitude, give rise to reible and unusual wastage effects on the surface of these glaciers, of Which the giant ice-pinnacles, and other penitente forms are examples. These same factors, coupled with the condition of the ice, have given rise to the very peculi troughs, verity able ice-valleys, that are such a remarkable feature of the glaciers of the northern side of the Himalaya.
The present glaciers appear to be in a state of stagnancy, or possibly extremely slow retreat. That they once extended much farther down for valleys is clear from the evience of moraine-shelves along the Rongbuk valley and elsewhere. These consist of four lateral moraines, or discontinuous portions of them, one above the other, occurring at heights of from 400 ft. to 800 ft. above the valley-floor, Whether these glaciers, during the maximum Pleistocene glacierization of the region, debouched far out towards the Tibetan plains ig not, from the available evidence, at present certain.
As to the study of the widespread post-glacial gravels along the southern border of the plains, and the extensive valley-terracing in the drainage-basin of the Arun River, an immense field lies open for further research. In the valley of E Chiblung Chu and elsewhere, data were collected which suggest that much of the terracing in those areas may have been due to climatic rejuvenation, consequent upon Pleistocene conditions, rather than to tectonic. further physiological data to amplify that obtained by his predecessors. This is now being examined, in particular samples of alveolar air, and the results will be published in due course. Specialists in this branch of science will be the first to admit that a vast amount of additional data is required before anything like a full understanding of many aspects of high-altitude physiology can be obtained.
Text read from the printed page and cleaned; old type leaves the occasional error.