DUCTILITY

(Lat.duco,/ rfraw.) A property of certain bodies, in consequence of which they can be drawn out at length without suffering any interruption of the continuity of their constituent particles. The term ductility is frequently confounded with malleability, or that property of bodies through which different forms can be given to them by pre ure or percu ion. In general ductility depends, in a greater or le degree, on the temperature^ Some bodies, wax for example, are rendered ductile by a small degree of heat; while gla requires a violent heat before it acquires ductility. Some of the metals — for example, gold, silver, lead, . — are ductile under all known temperatures. " The ductility of some metals far exceeds that of any other substance. The goldbeaters begin their operations with a riband an inch broad and 150 inches long, which had been reduced, by pa ing it through rollers, to about the SOOih part of an inch in thickne . The riband is cut into squares, which are disposed between leaves of vellum, and beat by a heavy hammer till they acquire a breadth of about three inches, and are thus extended to ten times their former surface. These are again quar  [s. 379]