What is it? - a possible answer

In response the question last year what is it (http://carconline.blogspot.com/2010/07/what-is-it.html) we received the following email from Arthur Missira:

"I don't blog so could not reply via that method; but happened across the newsletter and noticed that there had been no replies to the question.  "I suspect that it could be a 'four quadrant electrometer' and is usually described in old physics books ( pre 1950's )  "see:- http://en.wikipedia.org/wiki/File:Lord_Kelvin_quadrant_electrometer_engraving.jpg"
The full Wikipedia article on electrometers can found here: http://en.wikipedia.org/wiki/Electrometer , and an article on the interesting career of Lord Kelvin can be found here: http://en.wikipedia.org/wiki/Lord_Kelvin

If you want to experiment with an electometer, there are a couple of links at the bottom of the Wikipedia article with very simple circuits.