A highly interesting and instructive lecture on Electricity was then given by Mr. Cowley.

The subject was treated under these heads – the Nature, Kinds & Effects of Electricity.

It was shown that Electricity is not a distinct form of matter but, like heat is a condition of matter and that all substances may be brought into this condition.

Frictional – Electricity is that produced by the rubbing together of any two substances – hence the brushing of the coat of an assistant placed upon an insulating stool caused the leaves of a gold leaf Electroscope to diverge.

Voltaic – Electricity is that set free by chemical action, thus when any two metals are placed in a liquid which has a stronger chemical action upon one metal than the other, a current of Electricity is produced if the metals be made to touch either inside or outside the liquid. A needle and a pin upon being immersed in an inkpot & then connected with each other by a wire or other conductor caused a deflection of the needle of an astatic galvanometer placed in the circuit.

Magneto – Electricity was shown to be that produced by the movement of a magnet in proximity to a wire-covered piece of Iron or magnet – the current set up in the wire being momentary & in alternate directions & depending upon the character of the movement in the inducing magnet.

Therma – Electricity is the name given to the Electricity produced by the heating of the junction of two dissimilar metals.

Induced Electricity designates that caused by a coil of wire carrying a current in another coil of wire placed near it. These induced currents are momentary and depend, as regards frequency, tension, and direction, upon the movement of the current carrying wire or alterations in the strength or duration of the currents traversing it.

A Groves Battery of 20 cells which had been set up in an adjoining room was used to show experimentally some of the effects of Voltaic Electricity, the effects being thus classified – Chemical, Physiological, Heating and Luminous, the later being demonstrated by the production of the Electric Light.