Part 6 (1/2)

WIRING UP A HOUSE--The syste up a house so that all doors and ill be connected to for 61 It will be understood that, in practice, the bell is mounted on or at the annunciator, and that, for convenience, the annunciator box has also a receptacle for the battery The circuiting is shown diagramatically, as it is called, so as fully to explain how the lines are run Ts and a door are connected up with an annunciator having three drops, or numbers 1, 2, 3 The circuit runs from one pole of the battery to the bell and then to one post of the annunciator From the other post a wire runs to one terminal of the switch at the door orThe other switch ter to the other pole of the battery

A, B, C represent the circuit wires from the terminals of theand door switches, to the annunciators

It is entirely immaterial which side of the battery is connected up with the bell

Fro it will readily be understood how to connect up any ordinary apparatus, reht into the electric circuit

CHAPTER VIII

ACcumULATORS STORAGE OR SECONDARY BATTERIES

STORING UP ELECTRICITY--In the foregoing chapters we have seen that, originally, electricity was confined in a bottle, called the Leyden jar, frole impulse, as soon as it was connected up by external means Later the prienerate a constant current, and after these cae or secondary battery, and later still recognized as accumulators

THE ACcu, the more nearly correct, as electricity is, in reality, ”_stored_” in an accued by a current of electricity, a cheradually produced in the active elee or deco current is on When the accu battery or dyna system, or with a motor, for instance, a reverse process is set up, or the particles re-forinal compositions, which causes a current to flow in a direction opposite to that of the charging current

It is i source, whether it be by batteries or dynamos; the same principles will apply in either case

[Illustration: _Fig 62_ ACcumULATOR GRIDS]

ACcumULATOR PLATES--The elements used for accumulator plates are red lead for the positive plates, and precipitated lead, or the well-known litharge, for the negative plates Experience has shown that the best way to hold this62 shows the typical forrids It is made of lead, cast oror projection (B), at one rid is about a quarter of an inch thick

THE GRID--The open space, called the grid, proper, coral with the plate,62 shows three for to provide a form which will hold in the lead paste, which is pressed in so as toplate when completed

THE POSITIVE PLATE--The positive plate ismanner: Make a stiff paste of red lead and sulphuric acid; using a solution, say, of one part of acid to two parts of water The grid is laid on a flat surface and the paste forced into the perforations with a stiff knife or spatula Turn over the grid so as to get the paste in evenly on both sides

The grid is then stood on its edge, from 18 to 20 hours, to dry, and afterwards immersed in a concentrated solution of chloride of lime, so as to convert it into lead peroxide When the action is cohly rinsed in cold water, and is ready to use

THE NEGATIVE PLATE--The negative plate is filled, in likea strip of zinc into a standard solution of acetate of lead, and crystals will then forether, fir a porous mass This, when saturated and kept under water for a short tiative plate

[Illustration: _Fig 63_ assEMBLAGE OF ACcumULATOR PLATES]

CONNECTING UP THE PLATES--The next step is to put these plates in position to for 63 is shown a collection of plates connected together

For silass, porcelain, or hard rubber, with five plates (A), A, A representing the negative and B, B the positive plates A base of grooved strips (C, C) is placed in the batteries of the cell to receive the lower ends of the plates The positive plates are held apart by(D), which is clamped and held within the plates by a bolt (E), this bolt also being designed to hold the terative plates are held apart by the two tubular sections (G), each of which is of the sath as the section D of the positives The bolt (H) holds the negatives together as well as the terminal (I) The ter to the acid fumes which are formed, to coat all brass work, screws, etc, with paraffine wax

The electrolyte or acid used in the cell, for working purposes, is a pure sulphuric acid, which should be diluted with about four tiht in water Re acid to the water, and never pour the water into the acid, as the latter ood h of this solution into the cell to cover the tops of the plates, and the cell is ready

[Illustration: _Fig 64_ CONNECTING UP STORAGE BATTERY IN SERIES]