I now recrossed the Monte Rosa glacier to its junction with the Schwartze glacier, which descends between the Twins and Breithorn. The structure of the Monte Rosa glacier is here far less pronounced than at the other side, and the pressure which it endures is also manifestly less; the structure of the Schwartze glacier is fairly developed, being here parallel to its moraine. The cliffs of the Breithorn are much exposed to weathering action, and boulders are copiously showered down upon the adjacent ice. Between the Schwartze glacier and the glacier which descends from the breast of the Breithorn itself these blocks ride upon a spine of ice, and form a moraine of grand proportions. From it a fine view of the glacier is attainable, and the gradual development of its structure as the region of maximum pressure is approached is very plain. A number of gracefully curved undulations sweep across the Breithorn glacier, which are squeezed more closely together as the moraine is approached. All the glaciers that descend from the flanking mountains of the Goerner valley are suddenly turned aside where they meet the great trunk stream, and are reduced by the pressure to narrow stripes of ice separated from each other by parallel moraines. [Sidenote: TRIBUTARIES EXPLORED. 1858.] I ascended the Breithorn glacier to the base of an ice-fall, on one side of which I found large crumples produced by the pressure, the veined structure being developed at right angles to the direction of the latter. No such structure was visible above this place. The crumples were cut by fissures, perpendicular to which the blue veins ran. I now quitted the glacier, and clambered up the adjacent alp, from which a fine view of the general surface was attainable. As in the case of the Goernerhorn glacier, the gradual perfecting of the structure was very manifest; the dirt, which first irregularly scattered over the surface, gradually assumed a striated appearance, and became more and more decided as the moraine was approached. Descending from the alp, I endeavoured to measure some of the undulations; proceeding afterwards to the junction of the Breithorn glacier with that of St. Theodule. The end of the latter appears to be crumpled by its thrust against the former, and the moraine between them, instead of being raised, runs along a hollow which is flanked by the crumples on either side. The Breithorn glacier became more and more attenuated, until finally it actually vanished under its own moraines. On the sides of the crevasses, by which the Theodule glacier is here intersected, I thought I could plainly see two systems of veins cutting each other at an angle of fifteen or twenty degrees. Reaching the Goerner glacier, at a place where its dislocation was very great, I proceeded down it past the Riffelhorn, to a point where it seemed possible to scale the opposite mountain wall. Here I crossed the glacier, treading with the utmost caution along the combs of