This bridge (by Kohlrausch) was designed to measure the resistance of wires, objects containing electrolytes such as the human body, and contact resistances of earth plates and lightning arresters. It consists of a bank of resistors, a non-linear scale , and a small induction coil . This particular piece came to UVM in 1896 through James G. Biddle as a result of a gift from Edward H. Williams to the university of a new science building - including equipment and furniture. More here. | ||
Diagram showing external
connections. The resistance to be measured is connected to terminals
at the left. The telephone is used in place of a galvanometer when the induction
coil is being used for electrolytic resistance measurements.
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Various models of this device claim to measure resistances from .05 - 20,0000
ohms. The resistance is read directly from the scale.
For more information go
to
A Manual of Practical
Medical Electricity, Turner, 1904. ,
Electro-Medical Instruments
and Their Managment, Schall, 1902,
or
Price List 50, Physical Apparatus Vol III, Max Kohl,
191_. (Thanks to the person who sent me the first two references - due
to a hard drive failure I've lost your name/email. Please send me another
email so I can credit your contribution to this page)
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"Made By Hartmann & Braun Frankfurt A/M. Germany No. 582" | |
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