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crane, machine. The Columbia Encyclopedia, Sixth Edition. 2001-05 |
 | | Modern cranes are of varied types and sizes; they may be actuated by steam, electricity, diesel, or hydraulic power as well as by manual power, and they are indispensable in industries where heavy materials are handled constantly. |
 | | The jib crane has a horizontal load-supporting boom fastened to a rotating vertical column, either attached to a wall or extending from floor to ceiling; when the column is held only at the bottom it is called a pillar crane. |
 | | The derrick is a crane equipped either with a vertical mast held by struts, as on barges, or with guy wires, as in building construction. |
| www.bartleby.com /65/cr/crane-mac.html (360 words) |
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