ClipArt ETC
"Firmly fasten one end of a piece of spring-brass wire, about No. 27 and about 1 m. long so that the wire hangs vertical. To the lower end of the wire fasten a weight of 75 or 100 g. To this weight attach a pointer so that it extends horizontally from the direction of the wire. Turn the weight througha considerable angle, thus twisting the wire. Release the weight, and notice the rapid movements of the pointer of the torsional pendulum." -Avery 1895

Torsional Pendulum

"Firmly fasten one end of a piece of spring-brass wire, about No. 27 and about 1 m. long so that the…