CRANE

, a machine used in building, and in commerce, for raising large stones and other weights.

M. Perrault, in his notes on Vitruvius, makes the crane the same with the corvus, or raven, of the ancients.

The modern crane consists of several members or pieces, the principal of which is a strong upright beam, or arbor, firmly fixed in the ground, and sustained by eight arms, coming from the extremities of four pieces of wood laid across, through the middle of which the foot of the beam passes. About the middle of the arbor the arms meet, and are mortised into it: its top ends in an iron pivot, on which is borne a transverse piece, advancing out to a good distance like a crane's neck; whence the name. The middle and extremities of this are again sustained by arms from the middle of the arbor: and over it comes a rope, or cable, to one end of which the weight is fixed; the other is wound about the spindle of a wheel, which, turned, draws the rope, and that heaves up the weight; to be afterwards applied to any side or quarter, by the mobility of the transverse piece on the pivot.

Several improvements of this useful machine are mentioned in Desaguliers's Exper. Philos. pa. 178 & seq. particularly how to prevent the inconveniences arising from sudden jerks, as well as to increase its force by using a double axis in peritrochio, and two handles.

The Crane is of two kinds; in the first kind, called the rat-tailed crane, the whole machine, with the load, turns upon a strong axis: in the second kind, the gibbet alone moves on its axis. See Desaguliers, as above, for a particular account of the different cranes, and of the gradual improvements they have received. See also the Supplement to Ferguson's Lectures, pa. 3, &c, or Philos. Trans. vol. 54, pa. 24, for a description of a new and safe crane, with four different powers adapted to different weights.

Crane is the name of a southern constellation. See Grus.

Crane is also a popular name for a syphon.

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Entry taken from A Mathematical and Philosophical Dictionary, by Charles Hutton, 1796.

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COTES (Roger)
COVING
COUNTERSCARP
COURSE
CRAB
* CRANE
CRANK
CRATER
CREEK
CREPUSCULUM
CRONOS