–from Raymond Priestley’s book “Antarctic Adventure”–
“The day after the completion of the pick-and-shovel work in the cave we fixed up a neat door of biscuit-boxes and snow-blocks. Two biscuit-boxes were erected on end, one on either side of the entrance, the third was laid across the top, and then the rest of the entrance was filled in with snow-blocks. The upright boxes were then spaced so that we could pass the big cookers in and out without difficulty, and all crannies and holes were filled up with snow.
“It was now that we began to appreciate our blubber-lamps, for all daylight was excluded by the new door, and the lamps had to be kept burning all the time.”