PEOFESSOE TYI^DALL ON THE VEINED STEUCTUEE OP GLACIEES. 
289 
Let the observer now suppose himself transported to the Gornerhorn glacier, at some 
distance above the terminal moraine a ^ ; he will find there the transverse structure, if at 
all developed, excessively feeble and defective ; let him now walk downwards towards the 
moraine a h : every step he takes brings him to a place where the ice is subjected to a 
greater pressure, and every step also brings him to a better structure : both phenomena 
go hand in hand. At the end of the glacier, alongside the terminal moraine and under 
it, the structure is finely developed. If the observer now cross the glacier and ascend the 
rocks called Auf der Platte, from which he can command a near view of the Gornerhorn 
glacier, and embrace a large portion of it, he will be able to observe the gradual perfect- 
ing of the structure as the region of pressure is approached. Towards the extremity of 
the glacier the surface becomes wrinkled, the groovings denoting the structure become 
more and more pronounced, the dirt striae being more closely squeezed together ; and 
from these external aspects he may infer, with certainty, the gradual perfecting of 
structure within the glacier. 
The western glacier of Monte Rosa next commands our attention. Tliis great stream 
occupies the valley betAveen Monte Rosa and the Lyskamm, receiving the snows of the 
opposite sides of both. The branch of the Gorner glacier coming down from the Weiss- 
thor throws itself across the flow of its powerful neighbour, and deflects the latter, both 
of them afterwards moAing together doAvn the trunk valley, Avith a moraine, as usual, 
between them. 
Before quitting the “ Platte,” Ave AviU suppose that the observer has endeavoured to 
fonn some idea of the mechanical conditions of the Monte Rosa glacier. He would see 
the mass arrested in its descent by the Gorner glacier, and compelled to accompany the 
latter. A certain component of the weight of the glacier is borne by the ice Avhere it 
comes into contact with the Gorner glacier. The observer would infer, from mere 
inspection, that if the structm-e be due to pressm-e, it ought to be most fully developed 
near the moraine Avhich separates the Monte Rosa from the Gorner glacier. 
If he noAv pass from the “ Platte ” to the ice, and cross to the centre of the Monte 
Rosa glacier to A, he will And the structure there excessively feeble, if at all deA^eloped. 
Let him now walk straight doAvn the glacier towards B, where the pressure is most 
intense. Every step he takes downAvards brings him to more perfectly veined ice ; and I 
am not acquainted Avith a more splendid example of laminated structure than that exhi- 
bited by this glacier along tlie moraine, and for some distance from it, at its southern 
side. 
The system of glaciers Avhich next come under review are exceedingly instructive. 
In no place in the whole range of the Alps are the effects of pressure and the pheno- 
mena of structure more strikingly exhibited. I have endeavoured, in the sketch, to 
render the aspect of these glaciers intelligible. The Schwarze glacier moves doAvn a 
steep mountain slope, and welds itself to the Monte Rosa glacier at the bottom. But 
the great mass of this latter enables it to pursue its way without being compelled to 
swerve sensibly by its feebler neighbour. The latter is forced to bend abruptly, and 
