Description
The instrument does not produce electrical energy on its own. Instead, it functions as a receiver and distributor of charge within a larger experimental set up. For example, it generally would be connected to an electrostatic generator, a machine that produces high-voltage static electricity through friction (such as a Wilmshurst or Ramsden machine). The generator would transfer charge to the brass conducting element and the insulating glass would prevent the charge from leaking or escaping. The electric charge could be discharged for use, or transferred such as into a Leyden jar – a device capable of storing electricity.
Instruments such as these were common in physics classrooms, lecture halls, and private scientific collections during the mid-to-late 19th century, a time when the properties and uses of electricity was being investigated with rigor. These followed earlier experiments and discoveries by such pioneers in this field as Benjamin Franklin, Allessandro Volta, Michael Faraday, André -Marie Ampère, George Simon Ohm, James Prescott Joule and others. This led to new discoveries of charge conservation, attraction and repulsion, and discharge. Understanding that electricity could be stored ultimately led to the invention of the telegraph, the battery, electric motors, and eventually into the modern electronics of the 20th Century.
Condition: Generally very good with the usual light toning, handling, wear. Brass with only exceedingly minor and small abrasions or indentations.
References:
“Cylinder-type Electrostatic Machine.” American History. https://americanhistory.si.edu/collections/object/nmah_893450 (15 July 2025.
“Electrical Machines History.” Spark Museum. http://www.sparkmuseum.com/FRICTION_HIST.HTM. (15 July 2025).
