English: The force of attraction between two charged surfaces has been measured by an igenious modification of the common balance devised by Snow Harris. A light disk of gilt wood is substituted, as shown in fig. [185], for one the pans of the balance; beneath it is a second similar insulated disk: the suspended disk and the balance beam, through its support, are connected the exterior of a Layden jar, and the lower insulted disk the the interior of the jar. By charging the Layden jar with definite quantities of electricity by means of the unit jar, the laws which regulate the attractive force were experimentally determined.