PEOFESSOE TYNDALL ON THE VEINED STEUCTUEE OF OLACIEES. 
291 
One conclusive observation is still wanting to establish, the analogy between glacier 
lamination and the cleavage of slate rocks. In the latter case the arrangement of the 
strata has been traced by their organic remains ; and, indeed, stratification has often 
been visibly exhibited coexistent with cleavage, both crossing each other at a high angle. 
If a similar state of things could be detected upon a glacier, it would at once lay the 
axe to the root of all the scruples above referred to, and place the pressure theory upon 
an unassailable basis. The consciousness of this was sufficient to stimulate me in the 
search of such evidence. 
I had visited all the glaciers hitherto mentioned, and others not mentioned, without 
obtaining more than one clear case of the kind : this case I observed upon the Aletsch 
glacier on the 6th of August. Not far from the junction of the Middle Aletsch glacier 
with the trunk stream, a crevasse exposed a wall of ice 50 or 60 feet in height, upon 
which the stratification was exposed, and cutting the stratification at a high angle were 
the grooAngs which marked the true veined structure. The association was distinct ; 
my friend Professor Rajmsat was with me at the time ; I drew his attention to the fact, 
and to him the case was perfectly conclusive. Thus the Aletsch glacier, which had 
been referred to by Mr. Ball as furnishing evidence against the pressure theory, gave 
us a fact, which, as far as I could see, was perfectly fatal to the theory of stratifi- 
cation. 
But the case was solitary, and although inspiriting at the moment, its effect upon the 
mind became feeble as time passed, and no repetition of the observation occurred. I 
had remained at the Eiffel from the 9th to the 18th of August, exploring all the adja- 
cent glaciers, and adding each day to my stock of knowledge ; but I met no case in which 
the structure and the bedding were so clearly and independently exhibited, as to leave 
an adherent of the stratification theory no room for doubt. Wednesday the 18th of 
August was to be my last day at the Eiffel, and it was devoted to the examination of 
the Furgge glacier, which occupies the space between the pass of St. Theodule and 
the Matterhorn. 
Crossing the valley of the Gorner glacier, I climbed the opposite mountain slope, and 
passing the Schwarze See, soon came upon the glacier referred to. I walked up it until 
I found myself in a kind of cut de sac, flanked by precipitous ice-slopes, and opposed in 
front by a cascade composed of four high terraces of ice. The highest terrace was com- 
posed principally of broken cliffs and peaks of ice, and it had let some of its frozen 
boulders fall upon the platform of the second terrace, where they stood like rocking- 
stones on the point of falling. The whole space at the foot of the fall was .covered with 
quantities of crushed ice, while some coherent masses, upwards of 200 cubic feet in 
volume, were cast to a considerable distance down the glacier. 
Upon the face of the terraces the stratification of the neve was beautifully shown. 
Above the fall the neve extends as a frozen plain, quite undisturbed, so that the bedding 
took place with great regularity ; and being broken through for the first time at the 
summit of the fall, the lines of stratification were peculiarly well defined and beautiful. 
