In 1938, Gerald Seligman, Tom Hughes, and Max Perutz visited the Jungfraujoch to take temperature readings; their goal was to study the transition of snow into firn and then into ice with increasing depth. They dug shafts as deep as 20 m by hand, and also bored holes with augers of two different designs, including one based on advice provided by Hans Ahlmann. In 1948 Perutz returned to the Jungfrau, leading a project to investigate glacial flow on the Jungfraufirn. The plan was to drill a hole to the bed of the glacier, place a steel tube in the hole, and then revisit it for the next two years to measure the inclination of the tube at various depths. This would determine how the speed of ice flow varied with depth below the surface of the glacier. General Electric was engaged to design the electrical heating element for the tip of the drill, but were late in delivering it; Perutz had to pick up the package at Victoria Station's left luggage as he was leaving the UK for Switzerland. The package was resting on top of other suitcases in the train onward from Calais, and in pulling down a suitcase Perutz accidentally knocked it out of the train window. One of his team members returned to Calais and organized local Boy Scouts to search the track for the package, but it was never recovered. When Perutz reached the Sphinx Observatory (the research station on the Jungfraujoch) he was advised by the head of the station to contact Edur A.G., a manufacturing firm in Bern; Edur manufactured electrothermal tools to bore open beer barrels, and were able to quickly fashion a satisfactory drill tip. Perutz returned with the new drill tip to find that his two graduate students, whom he had left learning to ski while he went to Bern, had both broken their legs. He was able to persuade André Roch, who was then at the Institute for Snow and Avalanche Research at Weissfluhjoch, to join the project, and more students were sent from Cambridge as well.