X. On a New Electrometer, and the Heat excited in Metallic Bodies by Voltaic Electricity

1. In the course of some inquiries concerning the power of metallic substances to conduct intense electrical explosions, an account of which was honoured by a place in the Philosophical Transactions for the year 1827, I sought to obtain a comparative measure of the conducting power, in the heat evolved by the metal, at the time of transmitting the charge. The instrument employed for this purpose, was, in principle, that of a common air thermometer, the given metal, the subject of experiment, being drawn into a wire, and passed air-tight across its bulb. This simple contrivance, I have since extended to the general purposes of an electrometer, so as to estimate the force of any ordinary electrical accumulation. The results arrived at with voltaic combinations, seem, for the most part, of much practical utility; and therefore some account of them may, I trust, be found worthy of the attention of the Royal Society of Edinburgh.