Push-button. A switch for closing a circuit by means of pressure applied to a button. The button is provided with a spring, so that when pushed in and released it flies back, reopening the circuit.
Pyrogravure. A process of engraving by the use of platinum points heated to redness by the electric current.
Q
Q. Abbreviation or symbol for electric quantity.
Quadrant. The quarter of a circle or of its circumference.
Quadruple Circuit. (See [Circuit, Quadruple].)
Quantity. The term is applied to express arrangements of electrical connections for giving the largest possible amount of current.
Quantity, Electro-magnetic. The electro-magnetic current measured by its intensity for a second of time.
Quick-break. A break affected in an electric current by the employment of a quick-break switch.
Quickening. The amalgamating of the surface of a metallic object before electro-plating it with silver. This secures better adhesion of the deposit, and is done by dipping the article into a solution of mercurial salts—one part of mercuric nitrate to one hundred parts of water.