Barlow's wheel

Structure of mechanism
Function	The object comprises a wooden base with four Bakelite feet, holding a toothed copper wheel which rotates on a horizontal shaft, a horseshoe magnet whose pole extremities are located on either side of the wheel, and two terminals (+/-). The lower part of the toothed wheel is in contact with a tray containing mercury and connected to the + terminal. One of the pivots of the horizontal shaft on which the wheel rests is connected to the - terminal. When the two terminals are connected to a battery, a vertical electric current runs through the wheel. The electromagnetic force created by the magnet acts on the part of the wheel carrying the vertical current and drives the wheel.
Dimension of mechanism	planar
Drive movement	Rotation
Output movement	Rotation

Application
Examples of application	The Barlow wheel is used to demonstrate that a conducting wheel can be set in continuous motion under the influence of a magnetic field and a moving current. It was probably used to illustrate the operating principle of an electric motor during class simulations, but it was also used by future teachers during their practical courses at the men’s and women’s teacher training colleges of Aurillac (Cantal), now the IUFM (University Teacher Training Institute).