When a force acts upon a body and the body moves in the direction of the force, the force does work. Hence, work is the action of a force through s.p.a.ce against resistance.

It is generally expressed in compound units of length and weight, as foot-pounds, meaning a pound raised one foot.

Work, Electric, Unit of.

The volt-coulomb, q. v., or watt-second, as it is often termed.

Working, Diode.

In multiplex telegraphy the transmission of two messages, simultaneously, over one wire. (See Telegraphy, Multiple.)

Working, Contraplex.

A variety of duplex telegraphy in which the messages are sent from opposite ends of the line, simultaneously, so as to be transmitted in opposite directions. (See Working, Diplex.)

Working, Diplex.

In duplex telegraphy the sending of two independent messages from the same end of the line in the same direction.

581 STANDARD ELECTRICAL DICTIONARY.

Working, Double Curb.

A method of working telegraph lines. When a signal is sent the line is charged. This has to be got rid of, and is an element of r.e.t.a.r.dation. In double curb working it is disposed of by sending a momentary current first in the reverse, and then in the same, and finally in the reverse direction. This is found to reduce the charge to a very low point.

Working, Hexode.

In multiplex telegraphy the transmission of six messages simultaneously over one wire. (See Telegraphy, Multiplex.)

Working, Pentode.

In multiplex telegraphy the transmission of five messages simultaneously over one wire. (See Telegraphy, Multiplex.)

Working, Reverse Current.

A method of telegraphy, in which the currents are reversed or alternated in direction.

Working, Single Curb.

A simpler form of telegraph signaling than double curb working. It consists in sending a reverse current through the line for each signal by reversing the battery connection.

Working, Tetrode.

In multiplex telegraphy the transmission of four messages simultaneously over the same line. (See Telegraphy, Multiplex.)

Working, Triode.

In multiplex telegraphy the transmission of three messages simultaneously over the same wire. (See Telegraphy, Multiplex.)

Work, Unit of.

The erg, q. v. It is the same as the unit of energy, of which work is the corelative, being equal and opposite to the energy expended in doing it. There are many other engineering units of work, as the foot-pound and foot-ton.

Yoke.

In an electro-magnet, the piece of iron which connects the ends furthest from the poles of the two portions of the core on which the wire is wound.

Zamboni's Dry Pile.

A voltaic pile or battery. It is made of discs of paper, silvered or tinned on one side and sprinkled on the other with binoxide of manganese. Sometimes as many as 2,000 of such couples are piled up in a gla.s.s tube and pressed together with two rods which form the terminals.

They maintain a high potential difference, but having very high resistance and slight polarization capacity, give exceedingly small quant.i.ties.

Zero.

(a) The origin of any scale of measurement.

(b) An infinitely small quant.i.ty or measurement.

582 STANDARD ELECTRICAL DICTIONARY.

Zero, Absolute.

From several considerations it is believed that at a certain temperature the molecules of all bodies would touch each other, their kinetic motion would cease, and there would be no heat. This temperature is the absolute zero. It is put at -273? C. (-459? F.)

[Transcriber's note; The modern value is 0? Kelvin, -273.15? C, or -459.67? F. The lowest reported temperature observed is 1E-10? K.]

Zero, Potential.

Conventionally, the potential of the earth. True zero potential could only exist in the surface of a body infinitely distant from other electrified bodies.

Zero, Thermometric.

There are three thermometric zeros. In the R?aumur and centigrade scales, it is at the temperature of melting ice; in the Fahrenheit scale, it is 32? F. below that temperature, or corresponds to -17.78? C.

The third is the absolute zero. (See Zero, Absolute.)

Zinc.

A metal; one of the elements; atomic weight, 65.1; specific gravity, 6.8 to 7.2.

microhms.

Resistance at 0? C. (32? F.), per centimeter cube, 5.626 Resistance at 0? C. (32? F.), per inch cube, 2.215

Relative resistance (silver = 1), 3.741

ohms.

Resistance of a wire, 1 foot long, weighing 1 grain, .5766 (a) 1 foot long, 1 millimeter diameter, 33.85 (b) 1 meter long, weighing 1 gram, .4023 (c) 1 meter long, 1 millimeter diameter, .07163