Leeds & Northrup Instrument ID Help? Galvanometer?/string electrometer?

pie4himm · Oct 24, 2010

Leeds & Northrup Instrument ID Help? Galvanometer?/string electrometer?

I have an instrument here with not many visible model numbers or otherwise to figure out what it is ? it weighs around 26 lbs. it is 17-1/2" X 10" X 9" (roughly) and has a wood "case" a brass tag states May 1, 1906 PATENTED...along with a Leeds & Northrup 15381 at the right lower corner...I think it might be a galvanometer or electrometer of some sort? used to measure very small electric "differences"?

taz42o · Oct 24, 2010

Re: Leeds & Northrup Instrument ID Help? Galvanometer?/string electrometer?

http://www.google.com/patents?id=aE...=gbs_selected_pages&cad=1#v=onepage&q&f=false

pie4himm · Oct 24, 2010

Re: Leeds & Northrup Instrument ID Help? Galvanometer?/string electrometer?

thanks taz42o

Mackaydon · Oct 24, 2010

Re: Leeds & Northrup Instrument ID Help? Galvanometer?/string electrometer?

Pie4himm: Welcome to Treasure Net !!

The slide-wire potentiometer was invented by Johann Christian Poggendorff (1796-1877) in 1841. This potentiometer is a Leeds and Northrup Type K model, which was a standard piece of apparatus in most college and university electrical measurements laboratories for the first half of the 20th century.

At the heart of the potentiometer is a long slide wire. In the Type K potentiometer this was in the form of a ten-turn coil, a design due to Kohlrausch. The potentiometer was used with an external standard cell and an external galvanometer. Using a potentiometer to make voltage measurements was somewhat slow, but you could read to 0.00001 Volt.

A pic and this narrative source can be found here:
http://physics.kenyon.edu/EarlyApparatus/Electrical_Measurements/Potentiometer/Potentiometer.html
Don.....