He was assured that this ice never melts, and that its thickness is greater in summer than in winter.

M.Helmersen adds, that to the best of his belief no one has investigated the cavern of Illetzkaya Zastchita since Sir R.Murchison's visit.
_The Ice-Cavern of the Peak of Teneriffe_.[118] This cave is at a height of 11,040 feet above the sea, and is therefore not far below the snow-line of the latitudes of the Canary Isles.

The entrance is by a hole 3 or 4 feet square, in the roof of the cave, which may be about 20 feet from the floor.

The peasants who convey snow and ice from the cave to the lower regions, enter by means of knotted ropes; but Professor Smyth had caused his ship's carpenter to prepare a stout ladder, by which photographic instruments and a lady were taken down.
On alighting on a heap of stones at the bottom, the party found themselves surrounded by a sloping wall of snow, 3 feet high, and 7 or 8 feet broad, the basin in which they stood being formed in the snow by the vertical rays of the sun, and by the dropping of water from the edges of the hole[119].

Beyond this ring-fence, large surfaces of water stretched away into the farther recesses of the cave, resting on a layer of ice, which appeared to be generally about 2 feet thick.