Instruments and Methods: A Prototype Hotpoint for Thermal Boring on the Athabaska Glacier

THE hotpoint described in this paper was designed for a geophysical expedition to the Athabaska Glacier which is situated in the Canadian R ockies, lat.52 ° IS' N., long."7 ° IS' W. (approximately) .The project was organized by the Universities of British Columbia and Alberta and financed by the National Research Council of Canada.The expedition, which was the first of several seasons' work on the glacier, took place in the summer of 1959.Thermal boring was one of the projects carried out and this, together with seismic, gravity and surface movement studies, formed part of a programme of research on the mechanics of ice flow.Power for drilling was provided by a two-stroke petrol driven motor-generator rated at 230 volts, 3,000 watts; its total weight was '40 lb.(64 kg .) .This was manufactured b y the American "Homelite" Company.The electrical output was made variable from 0-2 30 volts by the inclusion of a rheostat in the field circuit of the generator.The drill holes were cased