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A typical Quarry Derrick rigged to pulled blocks up an inclined plane. Booms were made of a stout pole with a secondary pole attached at the base that could be swung around and raised and lowered. It was the secondary pole that moved the stone. To pick up large blocks of stone quarriers used dog holes. Dog holes are small indentations on each end of the block. A cable with hooks at the each end of a line was placed in the holes, the cable was drawn up tight and thus was able to lift the block.
(left) A “dog hole” at one end of a block. They are generally about 3 inches in diameter and inch in depth. The Stone Quarries, Craigleith, near, Edinburgh, from where the New Town was built. Source: "Modern Athens: Displayed in a series of views: or Edinburgh in the Nineteenth Century....from original drawings by Mr. Thomas H Shepherd"
This is a close-up from the 1829 print above. These one several different variations on the Jib Crane design. A jib crane is essentially a crane with a fixed length horizontal boom or beam. It rotates around the central mast pole. (The workmen are either holding crowbars or jumper drills or mix of both.) Source: Connecticut Historical Collections by John Warner Barber circa 1840 This show another basic variation of the Jib Crane. . |
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