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Show For the most part, glide shoes were used to measure glide in the " Schilt" defenses at Stein and the " Dorfberg" defenses at Davos. This method has been described in ( 9). It produced about 300 measurements, supplemented by about 80 measurements with saw dust columns in the above- mentioned defenses. The latter method is described in ( 6). Valuable conclusions about the variations of glide with time were given by the recording measurement system of In der Gand ( 9). Scattered observations are also available from abroad. In the winter of 195V55, H. Wopfner conducted glide research on the Wattener Lizum in Tirol, and in the winter 1961/ 62, H. Frutiger did the same in avalanche release zones of the " Stanley" slide at Berthoud Pass and the " Bethel" slide at Loveland Pass, Colorado, USA. Earlier authors described the present- day " glide" as " creep". Figure 1 gives the nomenclature for snow cover movement as it is commonly used today. In the northerly fore- Alps up to around 2400 meters elevation, glide of several decimeters occurs during normal winters on slopes steep enough to require defenses. If weather conditions favor glide, it can reach as much as one or more meters and lead to the release of avalanches running on the ground. For the research slope " Mattstock" at Amden, we have calculated an average velocity of 3- 7 mm per day. The average of 290 measurements from the avalanche defense " Schilt" at This value refers to the horizontal component of the glide path ( horizontal glide path in Figure 1), while all other cited figures refer to the glide path measured parallel to the slope fall line. |