Definition of pit prop in English:

pit prop

noun

单词	pit prop
释义	Definition of pit prop in English: pit prop noun A large wooden beam used to support the roof of a coal mine. 坑木，坑柱，窑木 Example sentencesExamples Its cargo of pit props - used to hold up mine shafts - went into the sea and its crew overboard. By the 1930s a worker's camp had been established, and the forest produced wood for pit props and fencing. The mines provided wage labor and required a network of commerce to supply explosives, chemicals, timber for pit props, and food for the miners. The use of wood in the foundries and for pit props in the mines must have been considerable. It features pit props for roof beams, bricks from wash houses, a massive lump of coal for an alter and a half winding wheel on a wall.
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