In construction the dry cell is shown in Figs. 254 and 255, the former

showing its exterior and the latter exposing its internal construction.

The container is a zinc can which is lined with porous paper to prevent

the filler from coming into contact with the zinc. The zinc further is

the active electrode, the chemical destruction of which generates the

electricity. The parts enclosed in the container are: a carbon rod,

which acts as the positive pole; and the filler, composed of finely

divided carbon mixed with manganese dioxide and wet with a solution of

salammoniac. The composition plug, made of coal-tar products and rosin,

is intended to keep the contents of the can in place and prevent the

evaporation of the moisture. Binding posts attached to the carbon rod

and soldered to the can furnish the + and-poles.

In the action of cell, the salammoniac attacks the zinc in which

chemical action electricity is evolved. The electricity is conducted

to the carbon pole through the carbon and the salammoniac solution

which in this case is the electrolite. In the dissolution of the

zinc, hydrogen gas is liberated which adds to the resistance of the

cell and thus reduces the current. The presence of the hydrogen is

increased when the action of the cell is rapid and the decrease in

current is said to be due to _polarization_. The manganese dioxide is

mixed with the filler in order that the free hydrogen may combine with

the oxide and thus reduce the resistance. This process is known as

_depolarization_. The combination between the hydrogen and the oxide

is slow and for this reason the depolarization of batteries sometimes

require several hours. Dry cells are usually contained in paper cartons

to prevent the surfaces from coming into contact and thus destroying

their electrical action.

The best cell is that which gives the greatest amount of current for

the longest time. Under any condition the working value of a cell

is determined by the number of amperes of current it can furnish.

The current is measured by a battery tester such as Fig. 257. The

+ connection of the tester is placed in contact with the + pole of

the cell or battery and the other connection placed on the-pole. The

pointer will immediately indicate the current given out by the battery.

A new dry cell will give 20 or more amperes of current for a short

time but if used continuously the quantity of current will be reduced

by polarizing until but a very small amount is generated. A cell that

indicates less than 5 amperes should be replaced. If short-circuited,

that is if the poles are connected without any intervening resistance,

a large amount of current will be given but the cell will soon wear

out and possibly be ruined. A cell should, therefore, never be allowed

to become short-circuited. The voltage of a cell is practically

continuous and should be from 1.5 to 1 volt. It is quite possible that

a cell may possess its normal voltage and yet deliver little current;

the voltage of a cell does not indicate its working property. In order

to be assured of active cells they should be tested at the time of

purchase with an ammeter.

The moisture in the paste of a cell is that which forms the circuit

between the zinc and the carbon elements. If the paste has dried out

its resistance is increased and the cell generates little current. The

voltage of such a cell may be normal while the amperage is very low.

Cells in this condition may be revived by adding moisture to the paste

as a temporary remedy. This may be accomplished by puncturing the can

with a nail and adding water. A solution of salammoniac may be used

instead of water and the cell soaked to accomplish the same purpose;

this, however, is only a temporary expedient.

Temperature influences the working properties of an electric cell in

pronounced manner. The moisture contained in the cell is composed of

ammonium chloride and zinc chloride and consequently the resistance

of the cell increases with the fall of temperature; the effect of the

resistance thus added is a decrease in the flow of current. Batteries

should be kept in a temperature as nearly as possible that of 70°F. The

battery regains its normal rate of discharge when the temperature is

restored.

The normal voltage and amperage for a given make of cell is practically

the same for all. The size of the cell does not in any way influence

the voltage. Small cells and large cells are the same. The large

cells are advantageous only in that they give out a greater number

of ampere-hours of energy. All batteries are rated in the number of

ampere-hours of current they are capable of furnishing. The ampere-hour

represents an ampere of current for one hour. On this basis all

batteries are rated for the total amount of energy they are capable

of producing. If the battery is worked at a high current, its life is

short; if however, it is discharged at a low rate, its life should be

long. In all cases the product of the number of amperes and the number

of hours constitute the ampere-hours of energy produced.

=Battery Formation.=--For ordinary household work as that of operating

doorbells, etc., the cells which form a battery are joined in series,

that is the positive or carbon pole of one cell is joined to the zinc

or negative pole of the next. The cells so connected are placed in

circuit with the bell and push button. If by accident the two cells of

a battery are joined with both carbon poles or both zinc poles together

the battery will give out no current because the voltage is opposed.

[Illustration: FIG. 256.--Battery combinations.]

In the use of batteries for ignition as for gasoline engines,

automobiles, etc., the arrangement of the cells has frequently

a decided influence on the effect produced. In Fig. 256 _A_ is

represented four cells joined in series, that is the carbon or + poles

are joined with the zinc or-poles, alternately. Connected in this

manner if each cell gives 1.5 volts the battery will give 4 × 1.5 = 6

volts; the current, however, will remain as that of a single cell. If

the cells singly give 20 amperes, the battery will give 20 amperes.

When cells are connected in this form the current passes through each

cell in turn and is as much a part of the circuit as the wires. Should

one of the cells be “dead”--that is delivering no current--it will act

as additional resistance and the current is reduced.

When joined in multiple or parallel connection as in Fig. 256 _B_, in

which all similar binding posts are connected, the effect is decidedly

different. In the multiple connection all of the zincs are joined to

act as a single zinc and all of the carbons are likewise joined and act

as a single carbon. In such a combination the voltage will be that of

a single cell 1.5 volts, but the amperage will be four times that of a

single cell or 80 amperes.

The diagrams and following descriptions of possible combinations were

taken from a bulletin on battery connections issued by the French

Battery and Carbon Co.

By combining the series and multiple connections, as shown in Fig.

_C_, both the voltage and current can be increased over that delivered

by one cell. Referring to the figure, it is seen that in each of the

two rows of four cells the cells are connected in series. This would

produce 6 volts and 20 amperes for the series of four which may now be

assumed as a unit, so that the two rows can be imagined as two large

cells, each of which has a normal output of 20 amperes at 6 volts. Now

by connecting the similar poles of two such large cells they are in

multiple and we get an increased current or 40 amperes and 6 volts,

which is the capacity of the eight cells connected as shown in the

figure. This is commonly designated as a _multiple-series_ battery.

Fig. 256 _D_ illustrates a multiple-series connection made in a

different manner, but which produces the same voltage and current as

the above mentioned. In Fig. _D_, two cells at a time are connected in

multiple, and these sets are then connected in series. The capacity of

each set of two is 40 amperes at 1-1/2 volts, and as these four sets

are connected in series the total output of the eight cells combined is

6 volts and 40 amperes, the same as that produced by the connections

shown in Fig. _C_.

Fig. _E_ shows the multiple-series connection illustrated in Fig. _D_,

applied to twelve cells in which four sets of three cells each are

wired in series, the three cells of a set being in multiple so that the

capacity of a set is 1-1/2 volts and 60 amperes. By connecting the

four sets in series as shown, the total capacity will be 60 amperes at

6 volts.

The use of the series-multiple connection is a distinct step forward

in dry-cell use. The arrangement of cells shown in Figs. _C_ or _D_ is

better than the arrangement in Fig. _A_, in just the same way that a

team of horses is better than a single horse. One horse pulling a load

of 2 tons may become exhausted in one hour, but two horses pulling that

same load may work continuously for six hours. It is true that in Fig.

_C_ there are twice as many cells used as in Fig. _A_, but the eight

cells in Fig. _C_ will do from three to four times as much work as

the four cells in Fig. _A_. In other words, while more cells are used

in the multiple-series arrangement, the amount of service per cell is

greater and the service is, therefore, cheaper in the multiple-series

arrangement.

Some battery manufacturers sell their batteries put up in boxes, the

cells being connected up in multiple-series and surrounded by pitch

or tar to keep out the moisture. This has certain advantages as well

as certain disadvantages. One of the objections to this method of

putting up dry cells is that if by any chance one cell out of the eight

or twelve which are buried in the pitch is defective it will run all

of the cells down, and being buried offers no means of detection or

removal. It is not possible to guarantee absolutely that a weak cell

will not be occasionally included in a large number, so dry cells may

be expected to vary to some degree among themselves.

It is interesting to know the effect of one weak cell on a

series-multiple arrangement. If, for example, in Fig. _C_ or Fig. _D_,

the dotted line connecting (_a_) and (_b_) be used to indicate a cell

which is partly short-circuited by internal weakness or external defect

the result is as follows:

In the arrangement shown in Fig. _C_, where one cell of the upper four

is short-circuited, the lower four will discharge through the upper

four even though the external circuit is not closed; that is, one

short-circuited cell will cause a run-down in all of the cells. In Fig.

_D_, however, one short-circuited cell will influence not the entire

set but the other one to which it is directly connected. There is thus

seen to be an advantage in the arrangement of Fig. _D_ and Fig. _E_,

over the arrangement in Fig. _C_.

In making connections between cells insulated wire should be used, or

special battery connectors are preferably employed. The ends of the

wires or connectors and the binding posts must be scraped clean so that

good electrical connection can be made between the two, and the knurled

nuts should be screwed tight into place. Care must also be taken that

the pasteboard covering around the battery is not torn. This would

allow contact between the zinc containers, and thus short-circuit the

cells. The batteries should be placed so that the zinc cans and the

binding posts of any cell do not come into contact with any other cell.

Vibration might cause enough motion for the brass terminal to wear

through the pasteboard of the neighboring cell and make contact with

the zinc can.

Different classes of work require different amounts of current at

different voltages and by choosing the proper combination of series,

multiple, or series-multiple connections practically every requirement

can be fulfilled. For electric bells, telegraph instruments, miniature

lights, toy motors with fine wire windings, etc., series connection is

recommended for the reason that the resistance of the external circuit

is high and a large voltage is necessary. For spark coils, magnets

and toy motors with large wire windings, multiple or series-multiple

connection of batteries should be used as a high voltage is not

required.

For some work, gas-engine ignition especially, it is economical to have

two complete sets of batteries, either of which can be thrown into

the circuit at will, so that while one set is delivering current the

other is recuperating. It has been estimated that by using two sets of

batteries, properly connected to give the desired current, the life of

each set is increased about four times. Thus it is seen that a saving

of 50 per cent. is effected in the cost of the batteries.

=Battery Testers.=--The “strength” of a cell is determined by the

amperes of current it is capable of producing; therefore, a meter that

will indicate the amount of current being produced is used to test the

current strength of the cell. Battery testers are made to indicate

voltage or amperage and sometimes the instrument is made to indicate

both volts and amperes. As explained above, the voltage of a cell is

not a true indicator of its strength. The ampere meter or ammeter, as

it is termed, is the proper indicator of the strength of the cell.

[Illustration: FIG. 257.--Battery tester.]

The common battery tester does not always give the exact number of

amperes of current, but it indicates the relative strength which is

really the thing desired. When the current from an active cell is once

shown on the dial of the tester, any other cell of the same intensity

will be indicated in like amount.

=Electric Conductors.=--Covered wire for carrying electricity is made

in a great variety of forms and designated by names that have been

suggested by their use. These wires are made of a single strand or in

cables, where several wires are collected, insulated and formed into a

single piece. Cables may contain any number of insulated wires.

The sizes of wires are determined by a wire gage. In the United States

the B. & S. gage is used as the standard for all wires and sheet metal.

The gage originated with the Brown & Sharp Mfg. Co. of Providence,

R. I., and has become a national standard by common consent. The

numbers range from No. 0000 to No. 60. The size of wire for household

electrical service ranges from No. 18 which is 0.04 inch in diameter to

No. 8 which is 0.128 inch across. The carrying capacities in amperes of

wires, as given by the Underwriters’ table of sizes from No. 8 to No.

18, are as follows:

+------+-------------+-------------+

| Wire | Rubber | Other |

| gage | insulation, | insulation, |

| No. | amperes | amperes |

+------+-------------+-------------+

| 8 | 35 | 50 |

| 10 | 25 | 30 |

| 12 | 20 | 25 |

| 14 | 15 | 20 |

| 16 | 6 | 10 |

| 18 | 3 | 5 |

+------+-------------+-------------+

=Lamp Cord.=--The flexible cord used for drop lights, connectors,

portable lamps, extensions, etc., is made of two cords twisted together

or two cords laid parallel and covered with braided silk or cotton.

The conductors consist of a number of No. 30 B. & S. gage, unannealed

copper wires twisted into a cable of required capacity. The conductor

is wound with fine cotton thread over which is a layer of seamless

rubber, and the whole is covered with braided cotton or silk. Lamp

cord is sold in three grades, old code, new code, and commercial, which

vary only in the thickness and quality of rubber which encloses the

conductor.

The new code lamp cord is identical with the old code form except that

it is required by the National Board of Fire Underwriters to be covered

with a higher quality of rubber insulation than was used in the old

form. The commercial cord is not recognized by the National Board of

Underwriters. It is practically the same as that described but does not

conform to the tests prescribed for the new code cord.

The sizes of the conductors enclosed in the lamp cord are made equal

in carrying capacity to the standard wire gage numbers. The sizes

ordinarily used are No. 18 and 20 gage but they are made in sizes from

No. 10 to No. 22 of the Brown & Sharp gage.

=Portable Cord.=--This is a term used to designate reinforced

lamp cord. The wires are laid parallel and are covered as with a

supplementary insulation of rubber. The additional insulation and the

braided covering assumes a cylindrical form. The covering is saturated

with weatherproof compound, waxed and polished.

=Annunciator Wire.=--This wire is made in the usual sizes and covered

with two layers of cotton thread saturated with a special wax and

highly polished. As the name implies it is used for annunciators, door

bells and other purposes of like importance.

=Private Electric Generating Plants.=--The conveniences to be derived

from the use of electricity were for many years available only by

those who lived in distributing areas covered by commercial electrical

generating plants. Except in towns of sufficient size to warrant the

erection of expensive light and power systems or along the lines of

electric power transmission, current for domestic purposes was not

obtainable.

Within a comparatively few years there have been developed a number

of small electric generating systems that are suitable for supplying

the average household with the electric energy for all domestic

conveniences. The combination of the gasoline engine, the electric

dynamo and the storage battery have made possible generating apparatus

that is operated with the minimum of difficulty and which supplies

all of the electric appliances that were formerly served only from

commercial electric circuits.

An electric generating system is commonly termed an electric plant.

It consists of an engine for the development of power, a dynamo

for changing the power into electricity and--to be of the greatest

service--a storage battery for the accumulation of a supply of energy

to be used at such times as are not convenient to keep the dynamo in

active operation.

Such a combination, each part comprised of mechanism with which

the average householder is unfamiliar, seems at first too great a

complication to put into successful practice. Such, however, is not the

case. The operation of small electric generating plants is no longer an

experiment. Their general use testifies to their successful service.

The working principles are in most cases those of elementary physics

combined with mechanism, the management of which is not difficult to

comprehend. Such plants are made to suit every condition of application

and at a cost that is condusive to general employment.

In a brief space it is not possible to enter into a detailed discussion

of the gasoline engine, the electric dynamo, and the storage battery

with the various appliances necessary for their operation; it is,

therefore, intended to give only a general description of the leading

features of each. The manufacturers of such plants furnish to their

customers and to others who are interested detailed information with

explicit instructions for their successful management.

The first private lighting plants were made up of parts built by

different manufacturers and assembled to form generating systems with

little regard to their adaptability. A gasoline engine belted to a

dynamo of the proper generating capacity supplied the electricity.

Neither the engines nor the dynamos were particularly suited to

the work to be performed, yet these combinations were sufficiently

successful to command a ready sale. The energy thus generated was

accumulated in a storage battery from which was taken the current for

a lighting and heating device. Besides the generating and storage

apparatus there is required in such a system, a switchboard, to which

are attached the necessary meters and switches that are required to

measure and direct the current to the various electric circuits.

Foresighted manufacturers, comprehending the probable future demand,

began the construction of the various parts, suited to the work and

the conditions under which they were to be employed. The manufacture of

apparatus, designed for the special service and composed of the fewest

possible parts, has reduced the operating difficulty to a point of

relative simplicity. Experience in the use of a large number of these

plants has revealed to the maker the course of many minor difficulties

of operation and the means of their correction. The mechanism has been

improved to prevent possible derangement and to simplify the means of

control, until the private electric plant is successfully employed by

those who have had no former experience with power-generating machines.

[Illustration: FIG. 258.--Household electric generating plant.]

As an example of the private electric plant Fig. 258 shows the

apparatus included in a combined engine, dynamo and switchboard,

connected with a storage battery. The relative size of the machine is

shown by comparison with the girl in the act of starting the motor.

This plant is of capacity suitable for supplying an average home with

electricity for all ordinary domestic uses. A nearer view of the

generating apparatus is given in Fig. 259 in which all of the exterior

parts are named. An interior view of the generating apparatus is

given in Fig. 260, in which is exposed all of the working parts. The

right-hand side of the picture shows all of the parts of the gasoline

engine that furnishes the power for driving the generator. This is

an example of an air-cooled gasoline engine in which the excess heat

developed in the cylinder is carried away by a drought of air. The air

draft is induced by the flywheel of the engine, which is constructed as

a fan. The blades of the fan, when in motion, are so set as to draw air

into the top of the engine casing and exhaust it from the rim of the

wheel. The air in passing takes up the heat in excess of that necessary

for the proper cylinder temperature. This form of cylinder cooling

takes the place of the customary water circulation and thus eliminates

its attending sources of trouble. In principle the engine is the same

as is employed in automobiles and other power generation.

[Illustration: FIG. 259.--Combined motor, electric generator and

switchboard.]

On the left-hand side is seen the dynamo and switchboard. The

dynamo armature is attached to the crankshaft of the engine by which

it is rotated in a magnetic field to produce the desired amount of

electricity. The brushes, in contact with the commutator, conduct the

electricity as it is generated in the armature, which after passing

through the switchboard is made available from the two wires at the top

of the board marked “light and power wires.” These wires are connected

with the storage battery and also to the house circuits through which

the current is to be sent.

[Illustration: FIG. 260.--Details of motor, electric generator and

switchboard.]

Referring to the switchboard of Fig. 259, the three switches and the

ammeter comprise the necessary accessories. The starting switch is

so arranged that by pressing the lever a current of electricity from

the storage battery is sent through the dynamo. The dynamo acting as

a motor starts the engine. When the engine has attained its proper

speed its function as a dynamo overcomes the current pressure from the

battery and sends electricity into the cells to restore the expended

energy, or if so desired the current may be used directly from the

dynamo for any household purpose. The box enclosing the switch

contains a magnetic circuit-breaker so constructed that when the

battery is completely charged the switch automatically releases its

contact and stops the engine.

The “stopping switch” at the right of the board and the “switch for

light and circuit” on the left are used respectively for stopping the

engine and for opening and closing the house circuits.

The meter performs a multiple function, in that it shows at any time

the condition of charge in the storage battery, the rate at which

current is entering or leaving the battery and also acts to stop the

engine when the battery is charged. At any time the pointer reaches the

mark indicated in the picture, the ignition circuit is automatically

broken and the engine stops. The fuses on the board in this case

perform the same function as those already described.

=Storage Batteries.=--These batteries have already been mentioned as

secondary batteries. They are sometimes called electric accumulators.

The electricity is stored or accumulated, not by reason of the

destruction of an electrode as in the primary cell but by the chemical

change that takes place in the plates as the charging current is sent

through the cell. When the battery is discharged, the current from the

dynamo is sent through the battery circuit in the reverse direction to

that of the discharge and the plates are restored to their original

condition. The action that takes place in charging and discharging is

due to chemical changes that take place in the plates and also in the

solution or electrolyte in which the plates are immersed.

There are two types of storage batteries, those made of lead plates

immersed in an acid electrolyte and the Edison battery which is

composed of iron-nickel cells immersed in a caustic potash electrolyte.

The former type is most commonly used and is the one to be described.

The lead-plate cell illustrated in Fig. 262 shows all of the parts of

a working element. The plates are made in the form of lead grids which

when filled to suit the requirements of their action, form the positive

and negative electrodes. The negative plates are filled with finely

divided metallic lead which when charged are slate gray in color. The

positive plates are filled with lead oxide. When charged they are

chocolate brown in color. In the figure there are three positive and

four negative plates which together form the element, then with their

separators are placed in a solution of sulphuric acid electrolyte. The

separators are thin pieces of wood and perforated rubber plates that

keep the positive and negative plates from touching each other and keep

in place the disintegration produced by the electro-chemical action of

the cell.

The unit of electric capacity in batteries is the ampere-hour. The

cell illustrated will accumulate 80 ampere-hours of energy. It will

discharge an ampere of current for 80 hours. If desired it may be

discharged at the rate of two amperes for 40 hours, or four amperes

for 20 hours, or at any other rate of amperes and hours, the product

of which is 80. The number of ampere-hours a cell will accumulate will

depend on the area of the positive and negative plates; large cells

will store a greater number of ampere-hours than those of small size.

The cells, no matter what size, give an average electric pressure of 2

volts.

The plates are joined by heavy plate-straps connecting all of the

positives on one end and all of the negative kind on the opposite end.

To insure rigidity the two sets are secured to the rubber cover by

locknuts. In this cell the plates are suspended from the cover. The

plate terminals are made of heavy lead connectors that when formed into

a battery are joined together with lead bolts and nuts.

[Illustration: FIG. 261.--Hydrometer for testing storage battery

electrolyte.]

The electrolyte is a solution of pure sulphuric acid in distilled water

and on its purity depends, in a great measure, its action and length of

life. The electrolyte is made of a definite density which is expressed

as its specific gravity. When fully charged the electrolyte will test

1220 by the hydrometer. That is, it will be 1.220 heavier than water.

When discharged it will test by the hydrometer 1185. This means that in

discharging the density has been reduced to 1.185 that of water. The

chemical change in the electrolyte is, therefore, an important part of

the charge and discharge of the cell. The density of an electrolyte

may be determined by a hydrometer such as Fig. 261. This is an ordinary

glass hydrometer such as is used for determining the density of fluids,

enclosed in a glass tube, to which is attached a rubber bulb. The point

of the tube is inserted into the opening at the top of the cell and the

electrolyte drawn into the tube by the reopening of the collapsed bulb.

The density is then read from the stem of the hydrometer.

=The Pilot Cell.=--In order to make apparent this density of the

electrolyte without the necessity of its measurement with a hydrometer,

one cell of the battery is provided with a gage as that of Fig. 262.

This is an enlargement of the end of the jar in which floats a hollow

glass ball of such weight that it will at any time indicate by its

position the relative density of the solution. When the cell is charged

the ball stands at the top of the gage and indicates a density 1220;

when discharged it is at the bottom and expressed by its position a

density of 1185. The electrolyte densities are the indicators of the

conditions of charge. The ball by its position shows at a glance the

quantity of electricity in the battery.

The voltage usually employed in household electric plants is that

of a battery composed of 16 cells. Since the normal voltage of a

storage cell is 2 volts such a battery joined in series is 32 volts.

This voltage for the purpose fulfills all ordinary conditions and is

generally employed. A battery of 16 cells, of 80-ampere-hour capacity,

will deliver current of 1 ampere for 80 hours at 32 volts intensity.

A 20-watt lamp on a 32-volt circuit requires 2/3 ampere for its

operation. The battery will, therefore, keep lighted one such lamp for

96 hours, or four 20-watt lamps may be lighted continuously for 24

hours, or eight lamps for 12 hours, before recharging.

Aside from its ability to supply the required light for the average

home, it furnishes energy sufficient for heating a flat-iron or other

heating apparatus, to operate motors for pumping water, driving a

washing machine or any other of the domestic requirements.

Such plants are made in sizes to suit any condition of requirement.

In large establishments a larger motor generator and battery will be

necessary with which to generate and store the required electricity

but in any case suitable apparatus is to be obtained to meet any

requirement of light, heat or power developed.

[Illustration: FIG. 262.--Electric storage cell.]

=National Electrical Code.=--The details governing the size, the

manner of placing and securing wires in buildings is included in the

regulations published by the National Board of Fire Underwriters as the

National Electric Code. Likewise the mechanical construction of all

apparatus dealing with electric distribution is definitely specified

so that manufacturers furnish reliable materials for all requirements.

In the specifications for furnishing buildings with the use of

electricity, descriptions are made of the desired types and styles of

the switches and various other fixtures to suit the requirements.

=Electric Light Wiring.=--In the equipment of a house for the use of

electricity, the wiring, together with distributing panel, the various

outlets, receptacles, switches, and other appliances that make up the

system, is of more than passing consequence. In the construction of the

electric system it is important that the wires and their installation

be done in a manner to meet every contingency.

The following descriptions for electric house wiring were taken from a

set of specifications published by the Bryant Electric Co. as applying

to buildings of wood frame construction. The specifications serve as

explanations for the appliances required in an ordinary dwelling. The

specifications are for the least expensive form of good practice in

wiring for frame buildings. They would not be permitted in large cities

where further protection from fire is required and where more rigid

rules are demanded by the Board of Fire Underwriters.

1. SYSTEM.--The circuit wiring shall be installed as a two-wire

direct current or alternating system. Not more than 16 outlets

or a maximum of 660 watts shall be placed on any one circuit,

allowing 110 watts for each baseboard plug connection or extension

outlet and 55 watts for each 16 candlepower lamp indicated at the

various wall and ceiling outlets on plans. All wiring shall be

installed as a concealed knob-and-tube system.

The type of wiring is designated as a two-wire direct or alternating

current system in order that there shall be no doubt as to the method

of wiring to be used. There are other methods that might be employed

that need not be discussed here.

The 16 outlets mentioned are intended to cover all lamps or plug

attachments that are to be used for heaters, fans, motors, or any other

electric device. The 660 watts at 110 volts pressure will require 6

amperes in the main wires of the circuit, which is the maximum current

the wires are intended to carry. This does not mean that 110-watt lamps

might not be used but that no single circuit shall carry lamps that

will aggregate more than 660 watts.

The concealed knob-and-tube system mentioned is illustrated in Figs.

263 and 264, in which the wires which pass through joists and studding

are to be insulated by porcelain tubes and those wires which lay

parallel to these members are to be fastened to porcelain knobs which

are secured by screws to the wood pieces to prevent any possibility of

coming into contact with electric conducting materials.

[Illustration: FIG. 263.--Manner of securing wires by the knob-and-tube

system for ceiling outlets.]

2. OUTLETS.--At each and every switch, wall, ceiling, receptacle

or other outlet shown on plans, install a metal outlet box of a

style most suitable for the purpose of the outlet. All outlet

boxes must be rigidly secured in place by approved method and

those intended for fixtures shall be provided with a fixture stud,

or in the case of large fixtures, a hanger to furnish support

independent of the outlet box.

=Outlet Boxes.=--For the safe and convenient accommodation of

switches, receptacles or other connections in the walls and ceilings

of a building, outlet boxes are used as a means of securing the wire

terminals to the receptacles. These boxes are made in a number of forms

for general application. One style is shown in Fig. 265. The boxes are

made of sheet steel and arranged to be secured in place with screws.

The box is further provided with screw fastenings to which the switch

or receptacle may be firmly attached.

[Illustration: FIG. 264.--This shows the knob-and-tube system of

securing the wires in partitions and the manner of fastening metal “cut

out” boxes; for switch, attachments, plugs, etc.]

3. INSTALLATION OF WIRES, ETC.--All wires shall be rigidly

supported on porcelain insulators which separate the wire at

least 1 inch from the surface wired over. Wires passing through

floors, studding, etc., shall be protected with porcelain tubes,

and where wires pass vertically through bottom plates, bridging,

etc., of partitions, an extra tube shall be used to protect wires

from plaster droppings. Wires must be supported at least every 4

feet and where near gas or water pipes extra supports shall be

used. All porcelain material shall be non-absorptive and broken

or damaged pieces must be replaced. Tubes shall be of sufficient

length to bush entire length of hole. At outlets the wires shall

be protected by flexible tubing, the same to be continuous from

nearest wire support to inside of outlet box. Wires installed in

masonry work shall be protected by approved rigid iron conduit

which shall be continuous from outlet to outlet.

The method and reasons for supporting the wires described above are

as have already been mentioned under item 1. The reason for extra

supports near gas pipes and water pipes is as a precaution against the

possibility of short-circuiting.

[Illustration: FIG. 265.--Outlet box.]

4. CONDUCTORS.--Conductors shall be continuous from outlet to

outlet and no splices shall be made except in outlet boxes. No

wire smaller than No. 14 B. & S. gage shall be used and for all

circuits of 100 feet or longer, No. 12, B. & S. gage or larger

shall be used. All conductors of No. 8 B. & S. gage or larger

shall be stranded. Wires shall be of sufficient length at outlets

to make connection to apparatus without straining connections.

Splices shall be made both mechanically and electrically perfect,

and the proper thickness of rubber and friction tape shall be then

applied.

Continuous conductors are required because of the possibility of

defects in the joints of spliced wire.

5. POSITION OF OUTLETS.--Unless otherwise indicated or directed,

plug receptacles shall be located just above baseboard; wall

brackets, 5 feet above finished floor in bedrooms, and 5 feet 6

inches in all other rooms; wall switches, 4 feet above finished

floors. All outlets shall be centered with regard to panelling,

furring, trim, etc., and any outlet which is improperly located on

account of above conditions must be corrected at the contractor’s

expense. All outlets must be set plumb and extend to finish of

wall, ceiling or floor, as the case may be, without projecting

beyond same.

6. MATERIALS.--All materials used in carrying out these

specifications shall be acceptable to the National Board of Fire

Underwriters and to the local department having jurisdiction.

Where the make or brand is specified or where the expression

“equal to” is used, the contractor must notify the architect of

the make or brand to be used and receive his approval before any

of said material is installed. Where a particular brand or make is

distinctly specified, no substitution will be permitted.

7. GRADE OF WIRE.--The insulation of all conductors shall be

rubber, with protecting braids, which shall be N.E.C. Standard

(National Electrical Code Standard).

8. OUTLET BOXES.--Outlet boxes shall be standard pressed steel,

knock-out type and shall be enameled.

9. LOCAL SWITCHES.--Local wall switches shall be two-button flush

type completely enclosed in a box of non-breakable insulating

material with brass beveled-edge cover plate finished to match

surrounding hardware.

Fig. 269 shows the various forms and grades of switches that there are

on the market. The screws which attach the plate to the switch enter

bushings that are under spring tension thereby preventing defacement

of the plate by overtightening of the screws. Single-pole is to be

used where the load will not be in excess of 660 watts; double-pole to

be used where the load is more then 660 watts or where for any other

reason it is desirable to break the current at both wires. Three-point

switches are to be used when a light or group of lights is to be

controlled, as hall lights that may be lighted or extinguished, from

either the top or at the bottom of a stairway. Four-point switches are

to be used between and two, three-point switches to control additional

lights. Where two or more switches are placed together an approved gang

plate is to be provided which designates the use of each switch. Where

indicated on the plan, clothes closets shall be equipped with automatic

door switch to connect the light when the door is open.

10. PILOT LIGHTS.--Switches controlling cellar, attic and porch

lights shall have pilot lamp in parallel on the load side of the

switch. The switch in Fig. 3 requires for its installation a

two-gang outlet box. The ruby bull’s-eye which covers the lamp is

practically flush, extending from the wall no further than the

buttons of the switch.

Pilot lights are intended to indicate the operation of other lights or

apparatus that cannot be directly observed.

The term bull’s-eye applies to a colored-glass button covering a

miniature lamp which burns whenever a light is used which is apt to be

forgotten and allowed to burn for a longer time than necessary.

11. PLUG RECEPTACLES.--Plug receptacles shall be of the

disappearing-door type, with beveled-edge brass cover plate

finished to match surrounding hardware (see Fig. 266). In this

receptacle the doors are pushed inward by the insertion of the

plug and upon its withdrawal close automatically, effectually

excluding dirt and concealing the live terminals. It is the latest

and best plug receptacle obtainable.

Plug receptacles are the attachments for the terminal pieces of plugs,

which temporarily connect portable lamps, electric fans or other

devices, they are made in many forms.

12. WALL AND CEILING SOCKETS.--One-light ceiling receptacles shall

be of a type to fit standard 3-1/4-inch or 4-inch outlet boxes.

Wall sockets shall be of the insulated base type. Sockets in

cellars shall be made entirely of porcelain and of the pull type.

All lamp sockets used in fulfilling these specifications shall

have an approved rating of 660 watts, 250 volts.

13. DROP LIGHTS.--Drop lights shall consist of the necessary

length of reinforced cord supported by an insulated rosette

with brass base and cover; the latter to cover 4-inch outlet

box, and furnished with a key socket complete with a 2-1/4-inch

shade-holder. Each drop cord shall have an adjuster.

14. HEATER SWITCH, PILOT AND RECEPTACLE.--Heating device outlets

shall be equipped with combination of switch, pilot light and

receptacle with plug and spare pilot lamp.

15. SERVICE SWITCH.--The service-entrance switch shall be 30

amperes, porcelain base with connections for plug fuses.

INSTALLATION OF SERVICE SWITCH.--Service switch shall be installed

in a moisture-proof metal box with hinged door.

PANEL CABINET.--The distributing panel cabinet shall be of steel

not less than No. 12 gage reinforced with angle iron frames, which

shall be securely riveted in place. Cabinet shall be larger than

panel to give at least 4-inch wire space around panel and shall be

given at least two coats of moisture-repellant paint.

DISTRIBUTING PANEL.--The distributing panel shall consist of

two-wire 125-volt branch cutouts, two-wire 125-volt porcelain-base

panel-board units, two-wire 125-volt porcelain-base deadfront

panel-board units. The distributing panel shall be surrounded with

an ebony asbestos or slate partition 1/2 inch thick which will

form a wire space around panel.

FUSES.--All fuses for branch circuits shall be not more than 10

amperes capacity. The contractor shall furnish the owner with

150 per cent. of required number of 125-volt plug-type fuses for

complete installation.

PANEL TRIM AND DOOR.--The panel trim and door shall be of steel,

with brass cylinder lock and concealed hinges, all furnished under

this contract. A directory of circuits and outlets served by panel

shall be enclosed in glass with metal frame, mounted on inside of

panel door.

HARDWARE.--All hardware furnished under this contract shall match

in quality and finish other adjacent hardware.

THREE-WAY CONTROL.--The nearest outlet at top and bottom of all

stairs and in entrance hall shall be controlled by three-way

switches located on separate floors where directed.

ELECTROLIER CONTROL.--Wherever there are ceiling outlets for

fixtures having three or more sockets controlled by wall switches

three wires shall be run between the switch box and the outlet to

permit the use of electrolier switches.

DINING-ROOM CIRCUIT.--Furnish and install in dining-room, where

indicated on plans, an approved floor box containing an approved

25-ampere plug receptacle. The wires connecting this receptacle to

the center of distribution shall be No. 10 B. & S. gage. Furnish

and deliver to whom directed an approved multiple-connection block

consisting of three individually fused plug receptacles. The

connection between the plug receptacle and this block shall be

made by means of 10 feet of No. 10 B. & S. approved silk-covered

portable cord with an approved 20-ampere cord connector 2 feet

from the multiple block.

HOUSE FEEDERS.--The size of the feeder from the service switch to

the panel board shall be figured in accordance with the National

Code rules for carrying capacity, allowing for all circuits being

fully loaded. The feeder shall be of sufficient size, however, to

confine the drop in voltage with all lights in circuit to 1 per

cent. of the line voltage.

SERVICE CONNECTION.--Make extension of house feeder overhead to

lighting company’s mains and make all connections complete to the

satisfaction of the light company and the architect. Furnish and

install the necessary frame or backboard for meter.

CALL BELLS.--The contractor shall furnish, install and connect

all push buttons, bells, buzzers and annunciators, as shown on

plans or therein described. All wiring shall be cleated in joists,

studs, etc., with insulated staples. Damp places, metal pipes of

all descriptions, flues, etc., must be avoided and wire fastenings

must be applied in such a way that insulation is not damaged. No

splices shall be made where same will not be accessible at any

time after completion of building. Wires shall not be smaller than

No. 18 B. & S. gage and shall be damp-proof insulated. Bells,

buzzers, buttons, etc., shall be of approved make. Push button

for main entrance door shall be provided with ornamental place

with approved finish. Push button in dining-room shall consist of

combination floor push, with necessary length of flexible cord and

approved portable foot push. Furnish and install where directed

three cells of carbon cylinder battery in a substantial cabinet.

BURGLAR ALARM.--Furnish and install complete burglar alarm

system consisting of the necessary wires, window springs, door

springs, night latch cutout for front door, bell, batteries,

cabinet, interconnection strip, etc., and everything required

for a complete open-circuit system. Each window sash and door

throughout the building shall be equipped with contact spring of

approved make and all springs on same side of building on each

floor shall be wired on one circuit and terminated on single-pole

knife switch on interconnection strip. The interconnection strip

shall be located as directed and shall have cutout switches for

each circuit as well as a double-pole battery switch. The battery

shall consist of at least three dry cells in suitable cabinet

placed where directed and both positive and negative leads shall

be carried direct to interconnection strip. The burglar-alarm

wires shall be not less than No. 16 B. & S. gage, insulated and

installed as specified for call bells.

INTERCOMMUNICATING TELEPHONES.--Furnish and install an

intercommunicating telephone system complete with all telephone

sets, wiring, batteries, etc. All wires to be cables containing

one pair of No. 22 B. & S. gage conductors for each station and

a pair of No. 16 B. & S. gage conductors for talking and ringing

battery respectively. Each pair of wires shall be twisted and all

pairs shall be twisted around each other to eliminate cross talk

and inductive noises. The wires shall be silk insulated, with a

moisture repellent of beeswax or varnish and the whole covered

with a lead sheath at least 1/64 inch in thickness. Where cables

terminate in outlet boxes they shall be fanned out and laced in

an orderly manner and secured to connecting terminals, one of

which shall be provided for each wire. Install where directed in

an approved cabinet at least four cells of dry battery each, for

talking and ringing purposes.

INSTALLATION OF INTERPHONE CABLE.--Intercommunicating cables shall

be supported with pipe straps and liberal clearance shall be

observed where near steam or other pipes.

=Automatic Door Switch.=--Where indicated on the plan, clothes closets

shall be equipped with automatic door switch to connect the light when

the door is open.

Fig. 266 is placed in the door frame in such position that electric

contact is made by release of the projecting pin as the door is

opened. When the door is closed, the pin is depressed and the light is

extinguished

=Plug Receptacles.=--Plug receptacles shall be selected from the styles

shown in Figs. 267,_a_, _b_, _c_ or _d_.

[Illustration: FIG. 266.--Automatic door switch.]

Fig. 267,_a_ is the disappearing-door type with beveled-edge brass

cover plate finished to match surrounding hardware. In this receptacle

the doors are pushed inward by the insertion of the plug and upon

its withdrawal close automatically, effectually excluding dirt

and concealing the live terminals. It is the latest and best plug

receptacle obtainable.

Fig. 267,_b_ is of the Chapman type with beveled-edge brass cover plate

finished to match surrounding hardware. In this receptacle the doors

open outward but are flush whether the plug is in or out.

[Illustration: FIG. 267.--Styles of plug receptacles.]

[Illustration: FIG. 268.--Heating-device receptacles.]

Fig. 267,_c_ is of the screw-plug type with beveled-edge brass cover

plate finished to match surrounding hardware. By many this is

preferred for apartment use as it will receive any style of Edison

attachment plug.

[Illustration: FIG. 269.--Service switches.]

Fig. 267,_d_ is of the removable-mechanism type with beveled-edge brass

cover plate finished to match surrounding hardware. The mechanism of

this receptacle is exchangeable with the mechanism of the double-pole

switch as shown in Fig. 270,_c_.

=Heater Switch, Pilot and Receptacle.=--Heating-device outlets shall be

equipped with combination of switch, pilot light and receptacle with

plug and spare pilot lamp. Figs. 268,_a_, _b_, _c_ and _d_, represent

various forms from which selection may be made. All are adapted for the

same purpose and differ only in mechanical arrangement.

[Illustration: FIG. 270.--Local wall switches.]

=Service Switch.=--The service entrance switch may be selected from the

three styles shown in Figs. 269,_a_, _b_, and _c_.

[Illustration: FIG. 271.--Pilot lights.]

[Illustration: FIG. 272.--Wall and ceiling sockets.]

Fig. 269,_a_ is composed of a 30-ampere porcelain base with connections

for plug fuses.

Fig. 269,_b_ is a slate base with connections for cartridge fuses.

Fig. 269,_c_ is a slate base with connections for open-link fuses

=Local Switches.=--Local wall switches may be selected from the various

styles shown in Figs. 270,_a_, _b_, _c_, _d_ and _e_.

Fig. 270,_a_ is the two-button flush type completely enclosed in a box

of non-breakable insulating material with brass beveled cover plate

finished to match surrounding hardware.

[Illustration: FIG. 273.--Drop-light attachments and lamp bases.]

Fig. 270,_b_ is a two-button flush type with brass beveled-edge cover

plate finished to match surrounding hardware.

Fig. 270,_c_ is of the removable-mechanism type with brass beveled-edge

cover plate finished to match surrounding hardware.

Fig. 270,_d_ is the single-button flush type with brass beveled-edge

cover plate finished to match surrounding hardware.

Fig. 270,_e_ is the rotary-flush type with brass beveled-edge cover

plate finished to match surrounding hardware.

=Pilot Lights.=--Switches controlling cellar, attic and porch lights

may be either Fig. 270,_a_ or _b_.

Fig. 270,_a_ requires for its installation a two-gang outlet box. The

ruby bull’s-eye which covers the lamp is practically flush, extending

from the wall no further than the buttons of the switch.

Fig. 270,_b_ is installed in a single-gang box. The lamp extends

through the plate and is protected by a perforated cage which extends

about an inch from the plate.

=Wall and Ceiling Sockets.=--One-light ceiling receptacles may be

selected from the types shown in Figs. 272,_a_, _b_, _c_, _d_ and _e_.

Fig. 272,_a_ is of a type to fit standard 3-1/4-inch or 4-inch outlet

boxes.

Fig. 272,_b_ is of the small concealed-base type.

Fig. 272,_c_ is of the large concealed-base type.

Fig. 272,_d_ is of the insulated-base type.

Fig. 272,_e_ is of the porcelain-base type.

Sockets in cellars shall be made entirely of porcelain. Those in

bathrooms shall be entirely of porcelain and of the pull type.

=Drop Lights.=--Drop lights shall consist of the necessary length of

reinforced cord supported by either brass or porcelain bases. Each drop

cord to have an adjuster. Figs. 273,_a_, _b_, _c_, _d_, _e_, _f_, _g_,

illustrate the various styles. Fig. 273,_h_ is a shade holder to be

used with the drop lights.

INDEX

A

Acetylene, gas burner, 302

gas machine, the Colt, 300

machines, 295

generators, types of, 297

stoves, 304

Air conditioning, 240

cooling plants, 244

discharged by a flue, 225

eliminators, 35, 36

properties of, table, 199

tester, the Wolpert, 233

valves, 19

Alcohol, sad irons, 289

table stoves, 293

Annunciators, 346

Anthracite, graphitic, 186

Atmospheric humidity, 196

B

Backventing, of plumbing, 105

Bathroom, 97

Bathtubs, 98

fixtures for, 100

Bibb, compression flange, 89

flange, 89

Fuller, 89

hose, 89

lever handle, 90

screw, 89

self-closing, 90

solder, 89

wash-tray, 91

Boiler, at end of season, 79

cast-iron, 19, 20, 38

cylindrical form of, 38

house heating, 19, 24

rules for management of, 77

sheet-metal, 19

Boiler, steam, rules for management of, 78

the house-heating steam, 19

Boyle’s law, definition, 161, 272

Briquettes, 189

British thermal units, 4

for one cent, 190

B.t.u., 2, 32, 182, 185

Burglar alarms, 344

Buzzers, 344

C

Candle, foot, 313

Hefner, 310

power, 310

horizontal, 310

spherical, 311

Cellar drain, 84

Cell, Pilot, storage battery, 370

Cesspools, 169

Charcoal, 188

Check-draft damper, 24

Chimney flue, the right, 79

Chimneys, “smokey,” 80, 81

Cisterns, filters for, 152, 153

galvanized iron tanks as, 152

rain-water, 151

wooden, 152

Clinkers, 72, 73

Close-nipples, 28

Coal, 182

anthracite or hard, 183, 193

bituminous or soft, 184

burning soft, 75

calorific value of typical American, 192, 193

cannel, 186

coking, 184

comparative value of, 189

free burning, 75

Coal, fusing-coking, 75

grades of soft, 184

pea size, 76

price of, 190, 191

semi-bituminous, 186, 193

Cocks, basin, 92

bibb, 88

corporation, 87

curb, 87

Fuller, 91

bibb, 89

repairs for, 91

pantry, 93

sill, 93

stop and drain, 88

stop and waste, 87

Code, national electric, 371

Coke, 76, 188

gas, 188

Column, the water, 22

Condensation, water of, 6, 10, 11, 15, 35

Conductors, 374

Cord, lamp, 363

portable, 363

Current, alternating, 332

direct, 332

D

Damper, ash-pit, 59

check-draft, 24, 67, 69, 70

direct-draft, 59, 61, 67

regulator, 59, 60

combined thermostat and, 67

for hot-water furnaces, 61, 62

for steam boiler, 60, 78

Design, heating plant, 44

Devining rod, 137

Dew-point, 209

to determine the, 212

Dim-a-lite, 323

Door bells, 342

Draft, economy of good furnace, 70

hand, regulation, 59

induced, 69

Drip-cock, 23

Dry cells, 354

E

Electric annunciators, 346

batteries, 354

battery formation, 358

testers, 360

burglar alarms, 344

buzzers, 344

conductors, 362

door bell, 342

dry cell, 355

flat-iron, 326

fuse plugs, 334, 337

generating plants, 363

heaters, 338

heating devices, 305

lamp cord, 362

lamps, Gem, 306

incandescent, 306

motors, 332

panel, 336

range, 340

signals, 341

stoves, 339

table pushes, 346

toaster, 330

Electrical measurements, units of, 317

Electricity, 305

Eliminator, air, 35, 36

Evaporation as a cooling agent, 243

F

Filaments, carbon, 308

incandescent lamp, 306, 307

tungsten, 307

Fire-box, 19, 20, 54

Firing, first day, 73

in moderate weather, 74

in severe weather, 74

night, 72

Fixtures, bathroom, 105

kitchen and laundry, 94

Flat-iron, electric, 326

Flues, furnace, 55

Flush tanks, 110

details of construction, 112, 113

low down, 111

Foot-candle, 313

Frost prediction, 212

Fuels, comparative value of coal to other, 189

danger from gaseous and liquid, 294

heating values of domestic, 252

moisture in, 194

Furnace, cast-iron, 54

firing, general rules for, 70

times of day for, 72

location of, 54

the hot-air, 51, 52

construction of, 52

Furnace-gas leaks, 54

Fuse plugs, 334

G

Gage, Bourdon type of, 23

electrified Bourdon spring pressure, 36

glass, 22, 40, 161, 162

steam, 22

water, 22

Gas, acetylene, machines, 295

all-oil water, 251

Blau, 251

burner, Bunsen, 275

open-flame, 278

coal, 250

lamps, mantle, 274, 276, 277

lighters, 302

measurements of, 253

meter dials, reading of, 255, 256

meters, 254

prepayment, 256

Pintsch, 251

service rules, 256, 257

ranges, 258

water, 251

Gases, heating values of, 252

Gasoline, 250

Beaumé test of, 261

Gasoline, boulevard lamp, 287

central generator plants for use of, 282

cold process system of lighting with, 264, 265

gas lamps, 286

gravity test of, 262

hollow-wire system of lighting and heating with, 269

lamps, inverted mantle, 279

portable, 280, 281

lighting and heating with, 259, 264

regulation and sale of, 261

sad irons, 289

stoves, burners for, 288

Gate valve, 94

Globe valve, 93

angle, 94

Grate surface, 53

Gravity system, low pressure, 6, 15

H

Heaters, combination hot-air and hot-water, 56

direct and indirect, 28

furnace hot-water, 122

instantaneous, 123

tank, 121

wash boilers, 96

Heating, C. A. Dunham’s system of vapor, 34, 35

direct indirect, 30

hot-water, 26

indirect method of, 29, 30

low pressure system of, 5, 6

overhead or drop system of steam, 14

system of hot water, 44

plants, management of, 70

separate return system of steam, 13

single pipe system of steam, 6, 12, 15

steam, 26

surface of furnaces, 56

Heating, radiators, 26

two pipe system of steam, 6, 10, 11, 15

Heat, of vaporization, 2

specific, 37

Hot-air furnace, 61

Hot-water heaters, 38

House drain, 82

Humidifying apparatus, 215

plants, 242

Humidity, absolute, 196

atmospheric, 196

control, 244

of the air, 196

relative, 197, 204

Hydraulic ram, 154

double acting, 157

single acting, 155

Hydrometer, storage battery, 368

Hygrodeik, 206

Hygrometer, 204

dial, 208

I

Illumination, 313

intensity of, 314

quantity of, 314

K

Kerosene, 263

legal tests for, 263

L

Lamp, base, the Edison, 311

cord, 363

labels, 312

Lamps, boulevard, 287

carbon filament, 311

central-generator gas, 286

daylight, electric, 324

gas-filled electric, 324

incandescent electric, 306

mantle, 276

inverted-mantle gasoline, 279

Lamps, Mazda, 310

miniature electric, 320, 325

portable, gasoline, 280

tantalum, 306

tungsten-filament, 306

turn-down electric, 321

Lights, drop, 383

flash, 326

pilot, 383

Lignite, 186

Lumen, 313

O

Outlet boxes, 373

Overflow pipe, 45

Overheated water, 47

P

Peat, 187

Pilot light, 375

Pipes, covering, 33

eliminator, 36

flow, 57

openings stopped, 113

overflow, 40, 41

return, 6, 10, 57

supply, 6, 10

Plant, hot-water heating, 37

steam heating, 1, 5

Plug receptacles, 378

Plumbers friend, 113

Plumbing, 81

rough, 82

Pneumatic motor valve, 237

radiator valve, 237

Polluted water, 134

Pollution of wells, 134

Pressure, absolute, 4

gage, 4

tank, 162

vapor, 35, 36

Properties of steam, 3

Psychrometer, 207

Pump, force, the, 146

lift, the, 144

tank, 146

Pumps, 144

chain, 151

deep well, 150

for driven wells, 150

priming of, 145

well, 148

wooden, 148

R

Radiating surface, 1, 21, 22, 27

Radiators, air vent on, 77

connections, 10, 47

corner, 28

finishings, 31

forms of, 26

hot-water, 28, 49

rules for proportioning, 24, 25

single column, 28

pipe, 10, 15

three column, 28

to control, 79

wall, 28

water-filled, 15

Range boilers, 115

blow-off cock, 118

double heater connections for, 119

excessive pressure in, 117

horizontal, 119

location, 118

Reflectors, 315

choice of, 316

focusing, 316

holoplane, 315

intensive, 316

Registers, rules for proportioning, 55

Regulator, combined thermostat and damper, 67

damper, 59, 60, 67

draft, 24

temperature, 59, 67

Riser, 6, 10

S

Sad irons, alcohol, 292

gasoline, 289

Safety valve, 24, 44, 47, 67

Septic tank, 170

and anaerobic filter, 174

automatic siphon for, 176

concrete, 179

limit of efficiency of, 178

Universal Portland Cement Co., 179

with sand-bed filter, 171

Sewage, 168

disposal, 168

purification, 168

Sewer, 82, 85

gas,114

Short circuiting, 334

Sitz bath, 98

Slicing bar, 72

Slugging, 15

Soil pipe, 84, 107

Soot pocket, 80

Stand pipe eliminator, 36

Steam temperatures, 4

Stop-cock, 46

Stove, acetylene, 292

gasoline, 288

putty, 54

Surface, grate, 53

air-heating, 53

Surging, 15

Switch, automatic door, 378

heater, 380

local, 382

service, 381

System, high-pressure hot-water, 41

low-pressure gravity, 6

hot-water, 38

overhead or drop, 14

separate return, 13

single pipe, 8

two pipe, 10

T

Table, air discharged from flues, 229

required for ventilation, 220

calorific value of American coals, 192

Table, dew-point, 210, 211

frost prediction, 214

heating values of coals, 93

gases, 252

wood, 187, 188

hot-air furnaces, 51

registers, 51

lumens per watt, 314

prices of fuels, 191

properties of air, 199

steam, 3

radiators, sizes of, 27

record of evaporation from hot-air furnace, 217

relative heating values of domestic fuel, 252

humidity, 202, 203

sizes of hard coal, 183

heating mains, 26

hot-air furnaces, 51

soft coal, 184

thermal units for one cent, 190

Table pushes, 346

Tank heaters, 121

expansion, 38, 40, 41, 45, 46, 47

Telephones, intercommunicating, 340

Temperature regulation, 59

hand, 59

pneumatic, 234

Thermostats, 62, 67

controllers, 62, 63

electric, 62

motor, 64

National Regulator Co., 235, 236

pneumatic, 62

time attachment, 63

Transformers, bell-ringing, 347

lamp, 316

Traps, Bower, 103

clean sweep, 103

drum, 103, 105

for bathroom fixture, 102, 103

inside, 83

non-siphoning, 105

outside, 83

sewer for house drains, 82

siphoning, 106

S, 103, 104

Try-cocks, 22, 23

Tungsten, 307

U

Union joint, 18

V

Vacuum, 5

Valve, air, 79

angle, 18

check, 42, 43

definition of, 88, 93

disc, 19

globe, 93

hot-water radiator, 49

Ohio hot-water, 49

on cellar mains, 78

safety, 24, 44, 47

steam radiator, 18

stem, 19

Valves, definition of, 93

globe, 93

Vaporization, heat of, 2

Ventilation, 219

apparatus, 239

by direct method of heating, 31

by indirect method of heating, 31

cost of, 230

De Chaumont standard of, 219

mechanical, 237

of dwellings, 222, 223, 224

Plenum method of, 239

quantity of air required for, 220

Vents, air, 16, 45, 48, 49

automatic air, 16

hot-water air, 50

Monash No. 16 air, 16

pipe, 83

radiator, 16

sewer, 85

the Allen float, 16

Voltage variation, effect of, 321

W

Wash stands and lavatories, 101

Waste stack, 84, 85

Water, ammonia in, 130

analyses, 126

artesian, 128

back, 115

chlorine in, 133

closets, 108

siphon-jet, 108

washdown, 109

washout, 108

frost, 115

hammer, 9, 15

hardness in, 131

iron in, 131

lift, 165

medical, 128

of condensation, 11

organic matter in, 130

overheated, 121

Pokegama, 127

polluted, 133

river, 127

seal, 83

softening with hydrated silicates, 132

supply, 87, 125

electric power, 164

plants, domestic, 158

gravity, 158

power, 163

pressure tank system of, 160

wind power, 164

table, 137

Wattmeter, periodic tests of, 354

readings, 352

recording, 350

state regulation of, 353

to read the, 350

Well, the ideal, 140

Wells, artesian, 140

bored, 141

breathing, 143

cleaning of, 142

concrete coverings for, 140

construction of, 138

curbing of, 136, 140

cylinders for tubular, 151

driven, 141

dug, 139

flowing, 138

freezing, 144

gases in, 142

open, 139

peculiarities of, 143

safe distance in the location of, 135

selection of the type of, 138

surface pollution of, 135

Wiped joints, 107

Wire annunciator, 353

Wiring, electric light, 372

Wood, 187

heating value of, 187

Transcriber's note:

Minor punctuation errors e.g. missing "." in "Fig." have been corrected.

Inconsistent hyphenation and use of ligatures has been left

e.g. cast-iron and cast iron. (Often the difference is between the

hyphenation in the text, that used in captions to illustrations

and that used in the index.)

Both gasolene and gasoline are used in the text

Both carburator and carburetor are used in the text

Many of the table values have errors which can be shown by graphing the

results, these have been left as printed but are noted here:

p.5. Absolute Pressure 5, Latent heat of 958.30 should be 956.30

p.199.

Air temperature 33 degF. Weight of cu. ft. air 566.4 should be 560.4

Air temperature 43 degF. Weight of cu. ft. air 548.4 should be 542.4

Air temperature 49 degF. Weight of cu. ft. air 542.5 should be 541.5

Air temperature 58 degF. Weight of cu. ft. air 534.9 should be 530.9

Air temperature 63 degF. Weight of vapor/cu. ft. air should be 6.45

p.203. Air Temp. 106,

2 deg. depression of wet-bulb thermometer 95 should be 93

p.211. Dew point. 69,

12 deg. depression of wet-bulb thermometer 84 should be 48

p.214.

Dry-bulb temp. 39,

12 deg. depression of wet-bulb thermometer 23 should be -23

Dry-bulb temp. 38

9 deg. depression of wet-bulb thermometer -6 should be 6

p.314. Column heading should read Watts per lamp 25 40 60 100 150 250

Other errors found:

Page | Original Corrected

number| text text

------+-----------------------------+---------------------------------

33 |asbestus plaster |Asbetos is used elsewhere but

| |this could be a trade name so it

| |has been left as printed.

55 |two layers of asbestus paper | As above.

56 |heating the house |The "us" in house was upside-down.

93 |pipe to which A is attached |A should be in italics.

100 |bath tubs, avatories |bath tubs, lavatories

133 |drinking porposes |drinking purposes

133 |elementary tract |alimentary tract

137 |It is flatest |It is flattest

161 |Boyles |Boyle's

162 |wtih the pump |with the pump

180 |its legnth |its length

181 |hould |should

188 |As given by Suplees |As given by Suplee's

216 |hydrodeik |hygrodeik

220 |Cubic feet or pure air |Cubic feet of pure air

239 |containg coils |containing coils

243 |sheet-met a surfaces |sheet-metal surfaces

259 |and explosion |an explosion

268 |The vitally improtant |The vitally important

269 |end of the supending bar |end of the suspending bar

269 |gasoline in the caburetor |gasoline in the carburetor

270 |gasoline for the stove _S_ | gasoline for the stove _R_

272 |Boyles law |Boyle's law

279 |Inverted-mantel Gasoline Lamp|Inverted-mantle Gasoline Lamp

281 |percolating trough the tube |percolating through the tube

305 |elect ic transmission |electric transmission

309 |the electrotromotive force |electromotive force

319 |1000 746 = 1.3 horsepower |1000/746 = 1.3 horsepower

320 |Minature screw base |Miniature screw base

329 |also shown in Fig. 288 | also shown in Fig. 228

343 |the contact peice |the contact piece

345 |window burgler alarm |window burglar alarm

347 |inserted in the floor place |inserted in the floor plate

352 |at the begining |at the beginning

356 |require severals hours |require several hours

357 |The amper-hour |The ampere-hour

358 |If the cells singly give |If the cells singly give

|20 volts, the battery will |20 amperes, the battery will

|give 20 volts |give 20 amperes

385 |Boyles' law, definition |Boyle's law, definition

387 |blau, 251 |Blau, 251

390 |DeChaumont |De Chaumont

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Mechanics of the Household A Course of Study Devoted to Domestic Machinery and Household Mechanical Appliances · 第 14 / 14 章