Two Tunnels in Cold ice at 4,000 m. on the Breithorn

Abstract

A description is given of two tunnels, each 60–70 m. long, one directly above the other, at 4,000 and 4,020 m, a.s.l. excavated through cold firn and ice of the Breithorn in the Alps. The temperature rose from −5.5° C. at the portal to −0.5^° C. at the rock interface 70 m, from the portal in the upper tunnel, and from −5.5° C. to 0° C. at a water reservoir 60 m. from the portal in the lower tunnel. In both cases cracks or minute sealed crevasses, cut by the tunnel, operated to cool the ice locally below the temperature to be expected from a smooth curve. Possible. origins of the water reservoir are discussed. Small amounts of air at a moderate pressure, enclosed in small, sealed cracks and hollows, were punctured between 60 and 70 m. from the portal in the upper tunnel. The pungent odor of the air thus released was identified as ozone (a) by its characteristic odor, (b) by its reaction on rubber, and (c) by potassium iodide starch paper tests. The source of such ozone is suspected to be minute electric sparks resulting from static electric charges built up in cold ice when it is subjected under pressure to cracking or deformation; Photographs taken with exposures of 8 hr. in the upper tunnel at night apparently show such sparks. A description is given of the appearance of cold ice, frozen to the bedrock, being forcibly tortured into streamers and bands by the movement of the entire ice body at 0.6 m./yr.