Page:Polar Exploration - Bruce - 1911.djvu/44

40 take nearly 1,200 years for that ice to reach the Barrier face. Meantime the whole glacier—or should it be called ice-field?—is accumulating ice by snowfall and by drift from the surrounding mountains and plateaux, and must therefore be chiefly and, indeed possibly, wholly composed of this in the form of névé, but with this marked character, that it is a moving, and not a stationary, névé. At some future time, with more space at my disposal, I propose to further discuss this point, because a general definition of a névé is ice that collects in a lofty plain, from which glaciers flow out but which does not actually flow itself. The structure of névé ice is also distinct from that of glacier ice, the grain of which, in each case, is the leading feature. The flow of the Ross Barrier is, I believe, different from that of an ordinary glacier which comes running and tumbling down a gully or a glen, like water in a river down a river course, for in this case it comes over a low stretch of flat or gently shelving land or shallow sea and is ultimately afloat. It is rather pushed from behind than moving forward by its own gravitation. The flow is probably different also in this respect, that, like a rapid river, there is a sort of rotatory movement of the ice of a glacier which is plastic by virtue of its disintegrated grains, each surrounded with a film