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Automobile
Engineering

J Genual Reference IVork

FOR REPAIR MEN, CHAUFFEURS, AND OWNERS; COVERING THE CONSTRUCTION,

CARE, AND REPAIR OF PLEASURE CARS, COMMERCIAL CARS, AND

MOTORCYCLES, WITH ESPECIAL ATTENTION TO IGNITION,

STARTING, AND LIGHTING SYSTEMS, GARAGE DESIGN

AND EQUIPMENT, WELDING, AND OTHER

REPAIR METHODS

Prepared by a Stuff of

AUTOMOBILE EXPERTS, CONSULTING ENGINEERS, AND DESIGNERS OF THE

HIGHEST PROFESSIONAL STANDING

Illustrated with over Fifteen Hnndnd En c ravin?

FIVE VOLUMES

AMERICAN TECHNICAL SOCIETY

CHICAGO

1917

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/ /-

AMERICAN TECHNICAL SOCIETY

Copyrighted in Great Britain
All Riffhts Reserved

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Authors and Collaborators

CHARLES B. HAYWARD

President and General Manager, The Stirling Press, New York City

Member, Society of Automobile Engineers

Member, The Aeronautical Society

Formerly Secretary, Society of Automobile Engineers

Formerly Engineering Editor, The Automobile

C. T. ZIEGLER

Automobile Engineer

With Inter-State Motor Company, Muncie. Indiana

Formerly Manager, The Ziegler Company, Chicago

MORRIS A. HALL

Formerly Managing Editor Motor IA/e, Editor The Commercial Vehicle, etc.

Author of "What Every Automobile Owner Should Know". "Motorists' First Aid

Handbook", etc.
Member. Society of Automobile Engineers
Member. American Society of Mechanical Engineers

DARWIN S. HATCH, B. S.

Editor. Motor Age. Chicago
Formerly Managing Editor. The Light Car
Member. Society of Automobile Engineers
American Automobile Association

*>»

GLENN M. HOBBS, Ph. D.

Secretary and Educational Director, American School of Correspondence
Formerly Instructor in Physics. The University of Chicago
American Physical Society

HERBERT L. CONNELL, B. S. E.

Lecturer in Charge, Automobile Division, Milwaukee Central Continuation School
Editorial Representative, Commercial Car Journal and Automobile Trade Journal
Member, Society of Automobile Engineers
Member. Standards Committee of S. A. E.
Formerly Technical Editor. The Light Car

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Authors and Collaborators (continued)

HUGO DIEMER, M. E.

Professor of Industrial Engineering;. Pennsylvania State College
American Society of Mechanical Engineers

HERBERT LADD TOWLE, B. A.

Specialist in Technical Advertising
Member. Society of Automobile Engineers
Formerly Associate Editor, The AutomotnU

ROBERT J. KEHL, M. E.

Consulting Mechanical Engineer, Chicago
American Society of Mechanical Engineers

EDMOND M. SIMON, B. S.

Superintendent Union Malleable Iron Company, East Moline, Illinois

EDWARD B. WAITE

Formerly Dean and Head. Consulting Department. American School of Correspondence)
Member, American Society of Mechanical Engineers

F. HALLETT LOVELL, Jr.

President and Treasurer, Lovell-McConnell Manufacturing Company

W. R. HOWELL

President, W. R. Howell and Company, London, England

WILLIAM K. GIBBS, B. S.

Associate Editor. Motor Age, Chicago

JESSIE M. SHEPHERD, A. B.

Head. Publication Department, American Technical Society

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Authorities Consulted

THE editors have freely consulted the standard technical literature
of America and Europe in the preparation of these volumes. They
desire to express their indebtedness, particularly, to the following
eminent authorities, whose well-known treatises should be in the library
of everyone interested in the Automobile and allied subjects.

Grateful acknowledgment is here made also for the invaluable co-oper-
ation of the foremost Automobile Firms and Manufacturers in making these
volumes thoroughly representative of the very latest and best practice in
the design, construction, and operation of Automobiles, Commercial Vehi-
cles, Motorcycles, Motor Boats, etc.; also for the valuable drawings, data,
illustrations, suggestions, criticisms, and other courtesies.

CHARLES E. DURYEA

Consulting Engineer

First Vice-President. American Motor League

Author of "Roadside Troubles"

OCTAVE CHANUTE

Late Consulting Engineer

Past President of the American Society of Civil Engineers

Author of "Artiacial Flight." etc.

E. W. ROBERTS, M. E.

Member. American Society of Mechanical Engineers

Author of "Gas-Engine Handbook." "Gas Engines and Their Troubles," "The Auto-
mobile Pocket- Book." etc.

SANFORD A. MOSS, M. S., Ph. D.

Member. American Society of Mechanical Engineers
Engineer, General Electric Company
Author of "Elements of Gas Engine Design"

GARDNER D. HISCOX, M. E.

Author of "Horseless Vehicles, Automobiles, and Motorcycles." "Gas, Gasoline, and
Oil Engines," "Mechanical Movements, Powers, and Devices," etc.

•*»

AUGUSTUS TREADWELL, Jr., E. E.

Associate Member, American Institute of Electrical Engineers

Author of "The Storage Battery: A Practical Treatise on the Construction. Theory, and
Use of Secondary Batteries"

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Authorities Consulted Continued

BENJAMIN R. TILLSON

Director, H. J. Willard Company Automobile School
Author of "The Complete Automobile Instructor"

THOMAS H. RUSSELL, M. E., LL. B.

Editor, The American Cyclopedia of the Automobile

Author of "Motor Boats," "History of the Automobile." "Automobile Driving:, Self*
Taught." "Automobile Motors and Mechanism," "Ig-nition Timing- and Valve Set-
tins." etc

CHARLES EDWARD LUCKE, Ph. D.

Mechanical Engineering Department, Columbia University
Author of "Gas Engine Design"

P. M. HELDT

Editor, HoreeUse Age

Author of "The Gasoline Automobile"

H. DIEDERICHS, M. E.

Professor of Experimental Engineering, Sibley College, Cornell University
Author of "Internal Combustion Engines"

JOHN HENRY KNIGHT

Author of "Light Motor Cars and Voiturettes," "Motor Repairing for Amateurs," etc.

WM. ROBINSON, M. E.

Professor of Mechanical and Electrical Engineering in University College, Nottingham
Author of "Gas and Petroleum Engines"

W. POYNTER ADAMS

Member, Institution of Automobile Engineers
Author of "Motor-Car Mechanisms and Management"

**»

ROLLA C. CARPENTER, M. M. E., LL. D.

Professor of Experimental Engineering, Sibley College, Cornell University
Author of "Internal Combustion Engines"

ROGER B. WHITMAN

Technical Director. The New York School of Automobile Engineers
Author of "Motor-Car Principles"

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Authorities Consulted— Continued

CHARLES P. ROOT

Formerly Editor, Motor Ag*

Author of "Automobile Troubles, and How to Remedy Them"

W. HILBERT

Associate Member, Institute of Electrical Engineers
Author of "Electric Ignition for Motor Vehicles"

SIR HIRAM MAXIM

Member, American Society of Civil Engineers
British Association for the Advancement of Science
Chevalier Legion d'Honneur
Author of "Artificial and Natural Flight." etc.

SIGMUND KRAUSZ

Author of "Complete Automobile Record," "A B C of Motoring"

JOHN GEDDES McINTOSH

Lecturer on Manufacture and Application of Industrial Alcohol, at the Polytechnic

Institute. London
Author of "Industrial Alcohol." etc.

FREDERICK GROVER, A. M., Inst. C. E., M. I. Mech. E.

Consulting Engineer

Author of "Modern Gas and Oil Engines"

FRANCIS B. CROCKER, M. E., Ph. D.

Head of Department of Electrical Engineering, Columbia University

Past President. American Institute of Electrical Engineers

Author of "Electric Lighting;" Joint Author of "Management of Electrical Machinery"

A. HILDEBRANDT

Captain and Instructor in the Prussian Aeronautic Corps
Author of "Airships Past and Present"

T. HYLER WHITE

Associate Member. Institute of Mechanical Engineers
Author of "Petrol Motors and Motor Cars"

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Authorities Consulted -Continued

ROBERT H. THURSTON, C. E., Ph. B„ A. M., LL. D.

Director of Sibley College, Cornell University

Author of "Manual of the Steam Engine," "Manual of Steam Boilers," etc

*,»

MAX PEMBERTON

Motoring Editor. The London Sphere
Author of "The Amateur Motorist"

HERMAN W. L. MOEDEBECK

Major and Battalions Kommandeur in Badischen Fussartillerie
Author of "Pocket- Book of Aeronautics"

EDWARD F. MILLER

Professor of Steam Engineering. Massachusetts Institute of Technology
Author of "Steam Boilers"

ALBERT L. CLOUGH

Author of "Operation. Care, and Repair of Automobiles"

W. F. DURAND

Author of "Motor Boats," etc

PAUL N. HASLUCK

Editor, Work and Building World
Author of "Motorcycle Building"

JAMES E. HOMANS, A. M.

Author of "Self-Propelled Vehicles"

R. R. MECREDY

Editor, The Encyclopedia of Motoring, Motor News, etc

S. R. BOTTONE

Author of "Ignition Devices." "Magnetos for Automobiles," etc

LAMAR LYNDON, B. E., M. E.

Consulting Electrical Engineer

Associate Member, American Institute of Electrical Engineers

Author of "Storage Battery Engineering"

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Foreword

THE period of evolution of the automobile does not span
many years but the evolution has been none the less
spectacular and complete. From a creature of sudden caprices
and uncertain behavior, it has become today a well-behaved
thoroughbred of known habits and perfect reliability. The
driver no longer needs to carry war clothes in momentary
expectation of a call to the front. He sits in his seat, starts his
motor by pressing a button with his hand or foot, and probably
for weeks on end will not need to do anything more serious
than feed his animal gasoline or oil, screw up a few grease cups,
and pump up a tire or two.

•L And yet, the traveling along this road of reliability and
mechanical perfection has not been easy, and the grades have
not been negotiated or the heights reached without many trials
and failures. The application of the internal-combustion motor,
the electric motor, the storage battery, and the steam engine to
the development of the modern types of mechanically pro-
pelled road carriages, has been a far-reaching engineering
problem of great difficulty. Nevertheless, through the aid of
the best scientific and mechanical minds in this and other
countries, every detail has received the amount of attention
necessary to make it as perfect as possible. Road troubles,
except in connection with tires, have become almost negligible
and even the inexperienced novice, who knows barely enough
to keep to the road and shift gears properly, can venture on
long touring trips without fear of getting stranded. Astonish-
ing refinements in the ignition, starting, and lighting systems

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have lately been effected, thus increasing the reliability of the
electrical equipment of the automobile as well as adding greatly
to the pleasure in running the car. This, coupled with the
extension of the electrical control to the shifting of gears and
other important functions, has made the electric current assume
a position in connection with the gasoline automobile second
only to the engine itself. Altogether, the automobile as a whole
has become standardized, and unless some unforeseen develop-
ments are brought about, future changes in either the gasoline
or the electric automobile will be merely along the line of
greater refinement of the mechanical and electrical devices used.

€L Notwithstanding the high degree of reliability already
spoken of, the cars, as they get older, will need the attention of
the repair man. This is particularly true of the cars two and
three seasons old. A special effort, therefore, has been made
to furnish information which will be of value to the men whose
duty it is to revive the faltering action of the motor and to take
care of the other internal troubles in the machine.

€L Special effort has been made to emphasize the treatment of
the Electrical Equipment of Gasoline Cars, not only because it
is in this direction that most of the improvements have lately
taken place, but also because this department of automobile
construction is least familiar to the repair men and others
interested in the details of the automobile. A multitude of
diagrams have been supplied showing the constructive features
and wiring circuits of the principal systems. In addition to
this instructive section, particular attention is called to the
articles on Welding, Shop Information, and Garage Design and
Equipment.

€L For purposes of ready reference and timely information so
frequently needed in automobile operation and repair, it is
believed that these volumes will be found to meet every
requirement.

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Table of Contents

VOLUME v
Electric Automobiles . By Charles B. Haywardt Page *11

Introduction— Storage Battery: Construction and Action of Typical Cell: Elec-
trolyte, Hydrometer, Forming Plate, Chemical Action on Charging Plate,

General Characteristics, Ironclad Exide Type. Starting Batteries, Edison Bat-
tery—Motor: Essentials of Motor— Principle of Rotation— Armature— Capacity
for Overloads— Parts of Motor— Motor Speeds— Transmission: Similarity to
Gasoline Practice— Usual Gear Reductions— Chain Drive— Gear Drive— Worm
Drive— Control: Counter E.M.F.— Controller— Methods of Control— Office of
the Shunt— Electric Brake— Caro and Operation of Electrics: Charging Bat-
tery: Sources of Direct Current, Sources of Alternating Current, Methods of
Charging. Testing Progress of Charge, Boosting— Care of Battery: Limits of
Discharge, Sulphating. Condition of Cells — Cleaning and Washing Batteries.
Avoiding Effect of Sediment, Treating Plates, Renewing Separators. Assembling
Cells, Charging Process After Washing— Compl ete Renewal of Battery: Dis-
mantling, Burning Groups, Reassembling' cells. Initial Charge, Test Discharge.
Recharging— Putting Battery Out of Commission: Storage, Packing the Battery,
Standard Instructions for Storage Batteries— Sources of Power Loss— Tires and
Mileage— Electric Indicating Instruments and Their Use— Summary of Instruc-
tions: Battery: Charging, Boosting, Methods of Charging, Discharge, Electro-
lyte, Voltage. Hydrometer Readings. Battery Jars. Connectors, Washing Bat-
tery* Efficiency — Power Usage: Motor Commutator, Brushes, Controller,
Instruments, Wiring, Fuses, Lamps, Low Mileage

Steam Automobiles . Revised by Herbert L. Connellt Page 197

Introduction: Development of Steam Engines. Characteristic Features of Steam
Cars— Heat Principles: Heat Transmission: Radiation and Absorption. Conduc-
tion, Convection. Expansion, Laws of Gases, Heat Transformation, Thermo-
dynamics of Steam. Superheating— Mechanical Elements of Steam Engine:
General Details— Slide Valve— Superheated Steam and Compound Expansion-
Valve Gears— Engine Types and Details: Stanley— Doble- National— Fuels and
Burners: Burner Principles, Pilot Light. Burner Types— Automobile Boilers:
Fire-Tube Types, Water-Tube Types, Flash Boilers, Special Types— Boiler
Accessories and Regulation: Check Valves, Stanley, Doble, Ofeldt— Manage-
ment and Care of Steam Cars: Management on the Road— Firing Up— At End
of Run— Engine Lubrication — Fusible Plug — Causes of Low Pressure — Scale
Prevention — Filling Boilers — General Lubrication — Water Pump — Gasoline
Pump— Engine Bearings— General Remarks on Operating

Commercial Vehicles . By Charles B. Haywardt Page 265

Introduction: Development of Field, Scope of Commercial Vehicle, Standard
Design. Classification— Electric Vehicles: Range of Use— Advantages— Power
Efficiency— Electric Delivery Wagon: Design. Motive Power, Shaft Drive, Worm
Gear Transmission, Shaft and Chain Transmission. Unit- Wheel Drive, Current
and Current Control. Brakes, Tires— Electric Tractors— Industrial Trucks— Elec-
tric Trucks: Classification. Character of Chassis — Gasoline-Driven Vehicles:
Gasoline Delivery Wagons: Autocar. White— Gasoline Trucks: Motor Design.
Ignition, Carburetors, Cooling Systems, Lubrication, Motor Governors, Clutches,
Transmission. Side-Chain Drive, Worm Drive, Double- Reduction Live Axle.
Internal Gear-Driven Axle. Differential Lock, Front Drives. Four- Wheel Drives
—Electric Transmission— Springs— Brakes, Trailers: Utilizing Excess Power,
Two-Wheel Types, Four-wheel Types— Gasoline-Driven Traction Engines:
Motor Design, Transmission, Types (Rumely, International. Hart- Parr, Samson.
Johnson, Auto-Tractor. Holt Caterpillar Tractor. Avery Tractor)

Glossary Page 359

Review Questions Page 389

Index Page 395

* For page numbers, see foot of pages.

t For professional standing of authors, see list of Authors and Collaborator! at
front of volume.

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ELECTRIC AUTOMOBILES

PART I

INTRODUCTION

The electric automobile was the natural and logical outgrowth
of the storage-battery street car, which, in the early 90's, w r as looked
upon as having a great future of commercial utility. That electric
vehicles were being manufactured and marketed on as general a scale
as the radical nature of the innovation would permit, as early as 1897,
is accordingly not surprising. The first step away from the time-
honored horse-drawn hack was the electric cab, a number of which
were placed in service on the streets of New York City as early as 1899.

Essential Features. At first the electric vehicle marked the
closest approach to the "horseless-carriage' ' ideal so much sought
after by builders in the earlier stages of the development of the
automobile, and, despite the example and precedents of the gasoline
machine, it was in many respects but an advanced replica of the many
forms of horse-drawn vehicles that served as its prototypes up to a
few years ago. Since then, the electric has been developed along
new lines, and, like the gasoline car, is a power-driven vehicle on
the design of which the precedents of horse-drawn-vehicle days no
longer exert any influence. Its essentials are few in number and
simple in construction. They* are, first, the storage battery, or
source of power; second, the electric motor, forming the medium
through which the current is transformed into mechanical energy;
and, third, the drive, or means by which the power of the motor is
in turn applied to the propulsion of the vehicle. Many works on
the subject have assumed a knowledge of the electric motor and
storage battery far in advance of that possessed by the average man,
and, lacking this, it is difficult, if not impossible, for the uninitiated
to appreciate the reasons why certain of the instructions that fol-
lowed should be rigidly adhered to, while others that were appar-
ently of an equal degree of importance could be slighted with more
or less impunity so far as detrimental results were concerned. With-
out a fundamental knowledge of underlying principles, the electric

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2 .. ELECTRIC AUTOMOBILES

vehicle owner or driver must naturally work in the dark, and while
blind compliance with the maker's instructions may be faithful at
the outset, failure to understand the reasons therefor sooner or later
leads to neglect.

Similarity of Types. Though there are quite a number of Amer-
ican-made electric vehicles at present on the market and, while most
of them .have been manufactured for a number of years, a little study
suffices to show that both in principle and construction, the majority
of these are very much alike. In fact, the similarity is so great that
the beginner will find no difficulty in applying the general knowledge
gained from the following pages to any vehicle he happens to possess,
or has a chance to examine. There are, naturally, differences in
design and in the details by which the power produced at the elec-
trical end is applied to driving the machine. Where these differ-
ences are of sufficient importance, they are described in detail, and
illustrations of the vehicles and their component parts are given, thus
making it easy to distinguish them.

FUNDAMENTAL FEATURES OF THE ELECTRIC
THE STORAGE BATTERY

There is probably no other single electrical device in general
use about which there is so much popular misconception as the
storage battery, or accumulator, as it is more technically known.
It does not in itself create a current of electricity — as does a primary
battery, such as the familiar dry cell, in which chemical processes
actually generate a current of electricity — and for this reason the
storage cell is called a secondary battery. The word storage in con-
nection with this type is really a misnomer, as the process by which
it absorbs and re-delivers electricity is not one of storage in any sense
of the word, but consists of chemical conversion and reconversion
upon a reversal of the conditions. As is the case with electric
vehicles, there are numerous different forms of storage batteries, for
many of which special advantages are claimed; but in general all
lead-plate batteries are very much alike, and a description of one
will make clear the principles upon which all are based. Theoreti-
cally, the principle of the Edison battery is also the same, i.e., that
of a chemical reaction upon the passage of the charging current

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ELECTRIC AUTOMOBILES 3

through the cell and a reconversion upon a reversal of the condi-
tions, but it differs so radically in practice that a detailed descrip-
tion of its construction is given.

CONSTRUCTION AND ACTION OF TYPICAL CELL

General Description. In order to obtain an understanding of
just how these processes are carried on, it is necessary to become
familiar with the internal action of the cell on receiving and dis-
charging a current and, for this purpose, it is essential to delve into
chemistry somewhat. Before taking up this subject, it may be well
to mention that a battery is comjwsed of a group of cells, each of which

Fig. 1. Typical Battery Plates

is a complete and self-contained unit, though the term battery is
indiscriminately applied to both. In a description of its working, a
cell is naturally referred to, as all are alike. A cell consists of two
seU of lead grids with pockets so cast in them that what is known as the
"active material" may be securely held even in case of severe jolting and
vibration. When filled with the active material, these grids are called
plates and are divided into two groups, one positive or + (plus) in
character, and the other negative or — (minus), of which typical
illustrations are given in Fig. 1 . As it is necessary, in order to obtain
maximum efficiency, to oppose a surface of negative capacity to each
surface of a positive nature, every storage cell will be found to have
one more negative than positive plate. It is possible to distinguish
them in this manner, where other indications are lacking, but as it is

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4 ELECTRIC AUTOMOBILES

most essential that they be known, the terminals or connections of the
groups are plainly marked by the makers either by the plus and minus
signs or in some other equally plain manner, such as painting the
positive terminal red. These groups of plates are known as electrodes
and are inserted in a jar containing a solution termed the electrolyte,
which consists of water and sulphuric acid. Fig. 2 shows a sec-
tional view of a small cell.

Electrolyte. The solution in which the elements of the storage
battery are immersed, or electrolyte, as it is termed, consists of

pure sulphuric acid and distilled,
or other pure, water. Concen-
trated sulphuric acid is a heavy oily
liquid having a specific gravity of
about 1.835. A battery will not
operate if the acid is too strong,
and it is therefore diluted with suf-
ficient water to bring it about 1 .275
for a fully charged cell. While a
battery is being discharged, the elec-
trolyte becomes weaker as part of
the acid is combined in the plates
in producing the current. This
weakening of the electrolyte causes
the specific gravity to drop 100 to
150 points during the complete

Fig. 2. Ambled storage Cell discharge. During the charge, this

acid is returned t6 the electrolyte,
thus increasing its strength until it again reaches the normal
gravity. There being no loss of acid, it is never necessary during
the normal service of a battery to add any acid to the cells.

Unless acid is actually knoivn to have been lost out of a cell, none
should ever be added during the entire life of the battery.

When the cells have been allowed to gas too freely, for reasons
that are explained later, there is more or less spray of acid through the
vent holes, but the amount of acid lost in this way is so small as to be
entirely negligible. The gravity of the electrolyte need not neces-
sarily be exact, as in a fully charged battery a range of from 1 .250 to
1 .300 is permissible.

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ELECTRIC AUTOMOBILES 5

Purity of Acid and Water. Both the acid and the water used in
making electrolyte should be chemically pure to a certain standard.
This is the same standard of purity in acid as is usually sold in drug
stores as "C P" (chemically pure), or by the chemical manufacturers
as "battery acid". In this connection, the expression "chemically
pure" acid is sometimes confused with acid of full strength, approxi-
mately 1.835 sp.gr., and at the same time chemically pure. If this
chemically pure acid of full strength be mixed with distilled water, the
mixture will still be chemically pure but not of full strength. On the
other hand, if a small quantity of some impurity be introduced into
the acid, it would not materially reduce the strength, but the acid
would no longer be chemically pure.

Determination of Strength of Acid. The usual method of deter-
mining the strength of electrolyte is by taking its specific gravity,
this method being possible because of the fact that sulphuric acid is
heavier than water. Therefore, the greater the proportion of acid
contained in the electrolyte, the heavier the solution or the higher
its gravity. By specific gravity is meant the relative weight of any
substance compared with distilled water as a basis. Pure water,
therefore, is considered to have a gravity of 1 . An equal volume of
chemically pure sulphuric acid weighs 1.835 pounds. It, therefore,
has a specific gravity of 1.835 and is referred to as "eighteen thirty-
five". As it is customary to carry the gravity readings out to three
decimal places, the gravity of water, which is 1, is written 1.000 and is
spoken of as "one thousand". These specific gravity readings are
usually taken by means of a hydrometer, shown in Fig. 3 and
discussed latter.

Temperature Correction. Since the electrolyte, like other sub-
stances, expands when heated, its specific gravity is affected by a
change in temperature. If electrolyte has a certain specific gravity
at 70° F. and is then heated, the heat will cause the electrolyte to
expand, and although the actual strength of the solution will be the
same as before heating, yet the expansion will cause it to have a lower
specific gravity, the difference amounting to approximately one point
(.001) for each three degrees rise in temperature. For instance, if
electrolyte has a reading of 1.270 at 70° F. and the temperature be
raised to 73° F., this increase in temperature will expand the electrolyte
sufficiently to drop its gravity from 1.275 to 1.274. On the other

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ELECTRIC AUTOMOBILES

TABLE I
Sulphuric-Acid Solutions*

Baaed on one part acid of 1.835 ap. gr. at 60° F.

Specific Gravity of

Parts of Water to One Part Acid

Percentage of*

Solution (7(T F.)

By Volume

By Weight

Sulphuric Acid
in Solutiom

1.100

9.8

5.4

14.65

1.110

8.8

4.84

16.

1.120

4.4

17.4

1.130

7.28

3.98

18.8

1.140

6.68

3.63

20.1

1.150

6.15

3.35

21.4

1.160

5.7

3.11

22.7

1.170

5.3

2.9

24.

1.180

4:95

2.7

25.2

1.190

4.62

2.52

26.5

1.200

4.33

2.36

27.7

1.210

4.07

2.22

29.

1:220

3.84

2.09

30.2

1.230

3.6

1.97

31.4

1.240

3.4

1.86

32.5

1.250

3.22

1.76

33.7

1.260

3.05

1.66

35.

1.270

2.9

1.57

36.1

1.280

2.75

1 49

37.3

1.290

2.6

1.41

38.5

1.300

2.47

1.34

39.65

1.320

2.24

1.22

42.

1.340

2.04

1.11

44.1

1.360

1.86

1.01

46.3

1.380

1.7

.92

48.4

1.400

1.56

.84

50.5

1.450

1.25

.68

55.5

1.500

.55

60.15

1.550

.44

64.6

1.600

.639

.348

69.12

1.650

.497

.27

73.32

1.700

.369

.201

77.6

1.750

.248

.135

82.1

1.800

.1192

.0646

87.5

1.835

93.19

* Courtesy of Electric Storage Battery Co.

land, if the temperature had dropped to 67° F., this would have
caused the gravity of the electrolyte to rise to 1 .276. Since cha nge of

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ELECTRIC AUTOMOBILES 7

temperature does not alter the strength of the electrolyte but merely
changes its specific gravity, the gravity reading should be corrected
one point for every three degrees change in temperature. For con-
venience, 70° F. is considered normal and is the point from which
corrections are made. This refers to the temperature of the electro-
lyte itself and not to that of the surrounding air. Table I shows the
parts of water by volume, the parts of water by weight, and the per-
centage of acid to water to produce different specific gravities.

Replacing Evaporation or Other Losses. The electrolyte, or solu-
tion, in the cell consists of a mixture of sulphuric acid and water; the
sulphuric acid does not evaporate, but the water does. When the level
of the electrolyte becomes low, it is due under normal conditions to the
evaporation of water, and this loss should be replaced with water only.
There being no loss of acid, it is never necessary during normal service
to add any acid to a battery. Of course, if a jar is upset and acid
spilled, or if a jar breaks and the acid leaks out, it must be replaced.
Care should be taken to see that the cells do not become flooded with
water when washing the car; this is apt to short-circuit them across
the lead connectors and if it enters the cells to disturb the specific
gravity of the electrolyte.

Unless acid is actually known to be lost out of a cell, none should
ever be added during the entire life of a battery. The amount of acid
lost in the form of spray due to the gassing of the cells is so small that
it may be neglected. Only distilled water or other water of approved
purity should be used for replacing evaporation. Most natural waters
contain impurities, some of which are chemically injurious to the
batteries, while others are not. Any water to be regularly used in a
garage for battery purposes without distillation should be submitted
to the battery manufacturer for approval.

It is necessary that the plates and separators be covered with
electrolyte at all times. When adding water, cover the plates about
\ inch. Do not put in more than this amount on the theory that if a
little is good more is better, since cells that are over-full tend to slop
while the car is running and will also be apt to lose electrolyte while
charging, as gassing raises the level of the solution in the cells.
Replace evaporation every five to fifteen days, depending upon the
conditions of service. The best time for adding water is just before a
charge. This may be done most conveniently with the aid of a

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8 ELECTRIC AUTOMOBILES

syringe of the type ordinarily used with a hydrometer. Keeping
the cells filled to the proper level with electrolyte is quite as important
as not allowing them to stand discharged for any length of time.
Adjusting the Specific Gravity. The best indication of the condi-
tion of a storage cell at any time is the specific gravity of its electrolyte
and the treatment to be given should always be governed by the latter.
The electrolyte of a fully charged cell of the vehicle type when first
put into service should have a specific gravity of 1.270 to 1.280.
Although this will change somewhat with age, the battery will con-
tinue to give good service between the limits of 1.250 and 1.300. If
the gravity should ever rise above 1 .300, it should be lowered promptly
by replacing some of the electrolyte with pure water. Low gravity
in a cell is usually caused by acid being combined in the plates through
lack of charge; although, if a jar has been upset and acid spilled, or
the jar is leaking, no amount of charging will bring its specific gravity
up to the proper point. A decreasing specific gravity in the electro-
lyte throughout the cells of an entire battery is an indication that
sediment is accumulating in the bottom of the jars and that the
battery requires washing. This is true, of course, only when the low
reading is not due to insufficient charging.

Before attempting to raise the specific gravity of any cell by
adding acid, charge the battery until certain that a maximum gravity
has been reached or, in other words, that no acid is still combined
with the plates in the cell. For example, if the electrolyte in a cell
should be adjusted to 1.275 when 50 points of acid still remain in the
plates, the gravity would rise to 1.325 if the cell were subsequently
charged to its maximum.

To adjust the specific gravity to its proper value (1.270 to 1.280),
first bring the battery to its true maximum, which can be assured only
by charging until there is no further rise in gravity during a period of
at least twenty-four hours of continuous charging at about one-half
the normal finishing rate. If, after this, the specific gravity is too
high, remove electrolyte down to the level of the plates with the
syringe and replace with pure water to £ inch over the plates; if
the specific gravity is too low, replace with 1.300 electrolyte, adding it
in small quantities to prevent bringing about the opposite condition.

When much adjustment is necessary and facilities are available,
as should be the case in a garage handling many electric vehicles,

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|
is
i

Trpc
V-I

TV pc
3-1

Fig. 3.

m
I

it is good practice to pour the electrolyte out of the cells into a glazed

earthenware vessel or a lead-lined tank, and to raise or lower the specific

gravity of this electrolyte as conditions demand. About one-third

of the electrolyte is held in the plates and the separators and cannot

be poured out, and this

should be allowed for in ^

estimating the proper

gravity before refilling SH

the cells. In cases where §fjj

there is a wide variation

between different cells,

further adjustment may

be necessary.

Hydrometer and Its
Use. The specific gravity
of a liquid is tested by
means of an instrument,
termed a hydrometer, con-
sisting of a weighted
glass tube having an
appropriate scale. The
depth to which this
instrument sinks in the
liquid to be tested shows
its specific gravity by the
reading of the scale at
the level of the liquid.
Fig. 3 shows the several
types of hydrometers,
while beside each is an t§
enlarged view of the Hz
scale. The Type V-l is
more commonly used
with electric vehicle bat-
teries, and Type S-l with
starting and lighting bat-
teries. Type M is employed in the battery rooms of central stations
where more exact readings are required.

Trpc
M

Types of Hydrometers for Determining
Specific Gravity

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10 ELECTRIC AUTOMOBILES

Where only occasional readings are taken a testing set, such as
that shown in Fig. 62, Part II, will serve all purposes, the acid being
transferred from the cell to the glass tube by means of the syringe,
putting in just sufficient to float the hydrometer clear of the bottom.
For constant use in connection with either vehicle or starting and
lighting batteries, the type shown in Fig. 61, Part II, is most practical.
The readings may be made more rapidly, and there is no danger of
spilling acid on the tops of the cells or on the hands. To prevent
the hydrometer from sticking to the sides of the barrel, it is necessary
to hold it vertically to take the reading. As some of the cells on
certain makes of cars are not so situated that the test can be made in
this way, the soft-rubber plug in the bottom of the glass barrel is
in the form of a trap so that when sufficient acid has been drawn into
the barrel, the hydrometer nozzle can be removed from the vent hole
of the cell and held in a vertical position, and the' acid will not run
out while the reading is being taken. WhereVer possible, however,
the reading should be made without removing the syringe from the
vent hole of the cell so that the acid thus withdrawn may be imme-
diately returned to the same cell.

Failure to replace the acid withdrawn for a test in the same cell
from which it was taken is apt to cause trouble. For example, if acid
is taken from one cell, and, after making the reading, it is replaced
in another cell, the result is that the amount of acid taken from the
first cell is later replaced with water, making the electrolyte that
much weaker. Likewise the acid which was put into another cell
will make the electrolyte of that particular cell correspondingly
stronger, resulting in lack of uniformity of the specific gravity of the
electrolyte in the different cells.

To simplify recording the gravity of the cells of a battery it is
customary to number them consecutively, beginning with the positive
cell in the front compartment of the car and following the cells in the
order of the electric circuit. If the trays are removed from the car,
this can be accomplished by numbering them in the same order,
i.e., beginning with the positive in the forward tray and marking it
Xo. 1 and so on through the entire battery, following the course of
the circuit itself.

As soon as sufficient electrolyte has been drawn into the barrel,
care being taken to see that the instrument is not sticking to the sides

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ELECTRIC AUTOMOBILES 11

of the latter, note underneath the level of the liquid the graduation on
the stem of the hydrometer. Reading the hydrometer by looking
at the level of the electrolyte from below is found to be more accurate
than looking down upon it from above. By having a gravity-record
form tacked on a suitable board and placed on the fender of the car
one man can easily take the gravity readings with the left hand and
note the results on the form with the right hand, which will avoid
spilling acid on the form or, what is more important, on the car
itself.

As has previously been explained, the gravity of the electrolyte
decreases as the batter}' is discharged, owing to the fact that a certain
percentage of the acid in the electrolyte is absorbed by the plates in
producing the current on discharge. In this way, during a normal
discharge, the specific gravity drops from 100 to 150 points, depending
on the type of cell. Consequently, by noting the gravity of the elec-
trolyte at any time and comparing it with that of full charge, the state
of charge can be determined approximately. In the section on "Elec-
trolyte" mention has been made of the fact that the temperature,
as well as the proportions of acid and water of which it is composed,
also affects the specific gravity of the solution. The gravity of the
electrolyte is assumed to be correct when the readings are taken
at 70° F. It becomes one point heavier for each three degrees below
70°, and one point lighter for each three degrees above.

For the convenience of the tester, a thermometer has been
designed with a special scale opposite the mercury column. This
scale corresponds to the temperature scale and indicates at a glance
the correction required for the temperature reading. See Fig. 9.
Opposite 70° it will be noted that the scale reads zero; above this the
correction is plus and below it minus. In making readings, however,
it is not customary to note a temperature correction for each, but
simply to record the temperature at which the tests are made, and if
the variation is sufficient to make the correction important, this is
done after all have been taken. The necessary temperature correc-
tions for the specific gravity are given from 30° to 100° F. in Table III,
Part II, but in this case the rated specific gravity for various stages
of charge is based on a temperature of 80° F. It is immaterial which
of these standards is adopted so long as the same one is uniformly
adhered to in testing all the cells of the same battery.

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12 ELECTRIC AUTOMOBILES

A hydrometer test, however, cannot always be considered as
conclusive evidence of the condition of a cell. The hydrometer
alone may sometimes be a very unreliable guide as to the charged or
discharged condition of a cell. For example, if electrolyte or acid
had just previously been added to the cell without the knowledge of
the tester, the hydrometer reading would apparently show the battery
to be fully charged w f hen the reverse might be the case. Conse-
quently, voltage tests must be used in addition as, in the instance just
cited, the voltmeter would give an indication directly opposite to that
of the hydrometer. Under average conditions, however, the hydrom-
eter alone will closely indicate the state of charge, though it is not
to be relied upon in all cases. When there is not enough electrolyte
in the cell to make it possible to use the hydrometer for a test, add
enough distilled water to restore the normal level and then charge
for at least one hour before making the test, as, when recently added,
the water will remain at the top of the cell, and the reading thus taken
will be valueless. Charging the battery mixes the water thoroughly
with the acid of the electrolyte.

Specific gravity readings between 1.275 and 1.300 indicate that
the battery is fully charged ; between 1.200 and 1.225 that the battery
is more than half discharged ; between 1 . 1 50 and 1 .200 that the battery
is nearing a fully discharged condition and must be recharged very
shortly, as otherwise serious damage will result; below 1.150 that the
battery is exhausted and must be recharged immediately.

Variations in Readings. Where the specific gravity in any cell
tests more than 25 points lower than the average of the others in
the battery, it is an indication that this cell is out of order. Depend-
ence should not be placed, however, on a single reading where there
is any question as to the specific gravity. Take several readings and
average them. Variations in cell readings may be due to short-
circuits inside the cell; putting too much water in the cell, causing
loss of electrolyte through overflowing; or to loss of electrolyte caused
by a cracked, or leaky, jar. Short-circuits may result from a broken
separator or from an accumulation of sediment in the bottom of the
jar reaching the plates.

When first testing the cells, low specific gravity in one or more of
them may often be equalized by charging, during which frequent
readings should be taken at short intervals. If the specific gravity

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ELECTRIC AUTOMOBILES 13

in any of the cells does not rise to 1.260 after the other cell readings
indicate that the battery is fully charged, it is an indication that the
low cell is in need of internal adjustment, and it must be dismantled
in accordance with the instructions given under that head. See also
instructions under "Renewal of an Element* ' for the method of
remedying the trouble.

Quite a substantial percentage of battery troubles — and this is
particularly the case with starting-system batteries that are usually
neglected until they give out — may be traced to letting the electrolyte
get too low in the jars. The effect of this is to weaken the battery,
thus causing it to discharge more readily and frequently resulting in
harmful sulphating of the plates and injury to the separators. When
the latter occurs, it permits the plates to come into contact and causes
an internal short-circuit. The importance of always maintaining
the level of the electrolyte \ inch above the tops of the plates by fre-
quent addition of distilled water to bring it up will be evident from
this. If, after the occurrence of low cells, the battery does not
regain its full efficiency after one or two days, it is an indication that
sulphating has taken place, and the remedy as given under that
heading should be applied without delay, as letting a battery go
without attention in this condition will ruin it.

One of the most frequent causes for low electrolyte in a cell is the
presence of a cracked, or leaky, jar, and if one of the cells requires more
frequent addition of water to maintain the level of its electrolyte, it is
a*n indication that it is leaking. Unless the jar is replaced imme-
diately, the cell itself will be ruined, and it may cause serious damage
to the remainder of the battery. Jars are often broken, owing to the
hold-downs becoming loose and allowing the battery to jolt around, or
it may be due to freezing. The presence of a frozen cell in a battery
shows that it has been allowed to stand in an undercharged condition
in cold weather, as a fully charged cell will not freeze except at very
low temperatures.

Frozen Cells. In some cases the cells may freeze without crack-
ing the jars. This will be indicated by a great falling off in the effi-
ciency of the cells that have suffered this injury or by a totally dis-
charged condition, which cannot be remedied by continuous charging.
In other words, the battery is "dead", and the plates are worthless
except as scrap lead. In all cases where cells have been frozen,

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14 ELECTRIC AUTOMOBILES

whether the jar has cracked or not, the plates must be replaced at once.
It must always be borne in mind that low temperatures seriously
affect the efficiency of the storage battery and this should be taken
into consideration when making hydrometer tests in cold weather.
The readings will not be the same in winter as they are in summer for

the same condition of charge.

Forming the Plate. The
first storage battery, invented by
Plants about half a century ago,
was composed of nothing more than
two plain plates of lead and this
solution. When a current is passed
through the cell, the acid attacks
the lead, depositing on the positive
plate lead peroxide (Pb0 2 ) and on
the negative plate pure spongy lead.
When discharged, the active mate-
rial changes to lead sulphate on
both plates and remains as a thin
film of new material on the surface.
If this charging and discharging is
repeated a number of times, this
film gradually becomes thicker.
Originally, storage batteries were
manufactured in this manner; but
the process was a lengthy and
„ . s tedious one, involving a number

Fig. 4. Empty Grid ' 6

of charges and discharges with
charges in opposite directions, extending over quite a period, with
the result that the active material thus made was loosely attached
to the surfaces of the plates and could easily be shaken off. This
is known as forming the plates, and, naturally, such a cell would
not be at all adapted to vehicle work, as the material frequently drops
of its own weight and would be instantly shaken off when subjected
to vibration. Instead, the plates are cast with the pockets already
mentioned, as shown in Fig. 4. This is the Faure, or pasted type of
plate, invented in 1881. The material is forced into the pockets
under great pressure, so that after the completion of this operation

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ELECTRIC AUTOMOBILES

the plate and material are practically integral. Fig. 4 shows an
empty grid, and Fig. 5 a completed plate of different make.

Chemical Action on Charging Plate. The number of charges
and discharges necessary to fit a cell
made in this manner for use is less than
by the old forming method. At the
beginning of the charge, both plates start
as lead sulphate and, combining with the
dissociated gases of the water in the
electrolyte, are converted into a spongy
form of metallic lead at the negative elec-
trode and peroxide of lead at the positive.
While an ability to read and understand
chemical formulas is not essential to
becoming familiar with these processes,
a knowledge of the latter is a consider-
able aid and serves to make them clear
with very little study. The fundamental
action of the cell, already referred to, is
expressed in a short series of equations
as follows:

CHARGE (read -«-«*) ^y^

(a) PbO,+H*S04 = PbS0 4 +H,0+0

(b) Pb +H,S04 = PbS04+H 2

DISCHARGE (read Wh+)

in which (a) is the reaction at
the positive plate, (b) the action
at the negative plate, and (c) the
combined process representing
the internal action of the cell on
charge and discharge. As the
deposit of spongy metallic lead
is formed at the negative elec-
trode and the peroxide of lead at the positive, the S0 2 is released and
combines with the water in the electrolyte to form sulphuric acid,
H2SO4. Reading from left to right as indicated for the discharge,
it will be apparent that the action consists of the change of lead

Fig. 5. Complete Battery Plate

2J5

f.lrt

2Tfl

200

10 n 20 2S 30 31

F3ft»*# of OvIpKuriaAckl in Efactroltfte .

Fig. 6. Variations in Density of Electrolyte
with Voltage of Cell

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16 ELECTRIC AUTOMOBILES

and lead peroxide, respectively, on the negative and positive ptales,
back into lead sulphate, as well as the reduction of the sulphuric acid
to water. The curve, Fig. 6, indicates the difference in the density
of the electrolyte, corresponding to the voltage.

Process of Charging. Precautions Regarding Electrolyte. To
charge, direct current is passed through the cells in the direction
opposite to that of discharge. This current passing through the cells
in the reverse direction reverses the chemical action w r hich took place
in the cells during the discharge. During the latter the acid of the
electrolyte penetrates the active material and combines with it,
filling its pores with lead sulphate and causing the electrolyte to
become weaker. Reversing the current through this sulphate in the
plates restores the active material to its original condition and returns
the acid to the electrolyte. This is why the battery manufacturer
lays such stress on his instructions never to add acid to the electrolyte
to bring up the specific gravity. Low gravity indicates that a large
proportion of the acid is combined with the active material of the
plates, and that when the cells are recharged this acid will be returned
to the electrolyte; thus any addition will represent an excess.

During the charge the electrolyte gradually becomes stronger,
as the sulphate in the plates decreases until no more sulphate remains
and all the acid has been returned to the electrolyte, when it will be
of the same strength as before the discharge, and the same acid will
be ready to be used over again in the next discharge. Since there is no
loss of acid, none should ever be added to the electrolyte. The acid
absorbed by the plates during the discharge is driven from the plates
by the charging current and restored to the electrolyte during the
charge. This is the whole object of charging.

Charging Rate and Time of Charge. It has been said that every
man has a different method of charging a storage battery, but this
refers to a variation in the detail of handling the charge rather than
the method, as the latter must naturally be the same in all cases, i.e.,
direct current must be passed through the cells in the right direction.
In the use of this current, there are only two factors to be considered,
rate in amperes, and time. The rate in amperes is limited by the
state of discharge. When the cells are fully discharged, in which
condition the plates contain the maximum amount of sulphate, the
charging current can be utilized at the highest rate.

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ELECTRIC AUTOMOBILES 17

Gassing. As the charge progresses and the amount of sulphate
in the plates decreases, they can no longer absorb current at the same
rate, and the charge must be reduced. This becomes necessary when
the cells begin to give off hydrogen gas. This is termed gassing and is
an important feature of the process of recharging, since gassing shows
at any time whether or not the charging rate is too high. Passing
current through a cell will always be followed by a reaction in the cell ;
just what this reaction will be depends upon the condition of the cell
at the time. In any case the current will always follow the path of
least resistance and will accordingly always do the easiest thing first.
When the cell is in a discharged state, the easiest thing is to decompose
the lead sulphate. As there is a comparatively large amount of lead
sulphate in a fully discharged cell, a correspondingly large amount of
current can be used in charging. But as the amount of sulphate
progressively decreases with the charge, a point is reached at which
there is no longer sufficient sulphate remaining to ultilize all the
current that is passing through the cell.

The excess current will then begin to do the next easiest thing,
which is to decompose the water of the electrolyte and produce gas.
Therefore, when the cells begin to gas freely, it indicates that current
is being passed through them at too high a rate, and the charge should
be reduced sufficiently to stop the gassing. As the charge is continued
at the lower rate, the remaining sulphate will continue to decrease in
amount until there is no longer sufficient to utilize the smaller amount
of current, and the cells will again begin to gas. The charge should
be reduced each time the gassing begins. When the cells begin to gas
freely at a very low charging rate, it indicates that there is practically
no sulphate remaining, so that even this small amount of current
cannot be utilized, and the charge is complete.

Discharge. The action of the cell on discharge is briefly as
follows: When the cell is connected up to discharge, the current is
produced by the acid in the electrolyte combining with the lead of the
porous parts of the plates, termed the active material which, as
already mentioned, consists of lead peroxide in the positive plates and
metallic lead in a spongy form in the negative plates. When the
sulphuric acid in the electrolyte combines with the lead in the active
material, a compound, lead sulphate, is formed. This is formed in
the same way that sulphuric acid dropped on the copper wiring, or

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18 ELECTRIC AUTOMOBILES

terminals, forms copper sulphate, or acid dropped on the iron work
of the car forms iron sulphate. In cases of this kind it will always
be noted that an amount of sulphate is formed out of all proportion
to the quantity of metal eaten away. In the same manner, the sul-
phuric acid of the electrolyte combines with lead in the plates forming
lead sulphate which, on account of its increased volume, fills the pores
of the active material.

As the discharge progresses, the electrolyte becomes weaker in
proportion to the amount of acid absorbed by the active material of
the plates in the formation of lead sulphate, a compound of acid and
lead. This lead sulphate continues to increase in quantity and bulk,
filling the pores of the plates, and, as these pores are stopped up by
the sulphate, the free circulation of the acid through the plates is
retarded. Since the acid cannot reach the active material in the
plates fast enough to maintain the normal action, the battery becomes
less active, as is evidenced by a rapid drop in voltage. Experiences
show that at the normal discharge rate, the voltage will begin to drop
very rapidly soon after reaching 1.8 volts per cell.

During a normal discharge, the amount of acid used from the
electrolyte will cause the gravity to drop 100 to 150 points. Thus, if
the gravity of a fully charged cell is 1.275, it will, at the end of the
discharge, be between 1.175 and 1.125, depending on the type of cell.
The battery should never be allowed to drop below this point, but
should immediately be placed on charge.

Efficiency of Storage Cell. About 20 per cent of the energy
employed in charging the cell is lost in the process, so that the effi-
ciency of the storage cell in good condition is approximately 80 per
cent, this representing the available output of the fully charged cell.
By abuse or neglect this percentage of efficiency may fall so low that
the figures given will be almost reversed, from which the necessity
for properly looking after the battery may be appreciated, particu-
larly when it is expressed in terms of miles per charge and the reduced
capacity may mean stranding at quite a distance from a source of
current. Fig. 7 shows a typical charge and discharge curve, while
Fig. 8 shows the peculiar discharge curve of a cell that has stood fully
charged for some time.

From the electrical point of view, the chief desideratum in a
cell is high conductivity of its components, as this makes for

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efficiency; but for vehicle use, strength, rigidity, and compactness are
very essential, and the attempt to reconcile these conflicting require-
ments is accountable for the varying forms and materials commer-

Mouro

Fig. 7. Typical Charge and Discharge Curves

cially employed for the purpose. It is for this reason that the grid
form mentioned, into which the material is pasted and then com-
pressed, has been adopted.

Sulphating. The conversion of the active material into lead
sulphate, which takes place during the discharge of the cells, is a

VWt.

zoc

»*

1110

its

1*0

Fig. 8.

* 3 -+

Houns

Peculiar Discharge Curve

normal reaction and as such occasions no damage. If, however, the
cells are allowed to stand for any length of time in a discharged condi-
tion, the sulphate not only continues to increase in amount but

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terminals, forms copper sulphate, or acid dropped on the iron wor
of the car forms iron sulphate. In cases of this kind it will alway
be noted that an amount of sulphate is formed out of all proportioi
to the quantity of metal eaten away. In the same manner, the sul
phuric acid of the electrolyte combines with lead in the plates forminj
lead sulphate which, on account of its increased volume, fills the pore
of the active material.

As the discharge progresses, the electrolyte becomes weaker in
proportion to the amount of acid absorbed by the active material of
the plates in the formation of lead sulphate, a compound of acid and
lead. This lead sulphate continues to increase in quantity and bulk,
filling the pores of the plates, and, as these pores are stopped up bv
the sulphate, the free circulation of the acid through the plates i>
retarded Since the acid cannot reach the active matenal in the
plates fast enough to maintain the normal action, the battery become,
less active, as is evidenced by a rapid drop in voltage Experience,
show that at the normal discharge rate, the voltage will begin to drop
very rapidly soon after reaching 1.8 volts per cell

During a normal discharge, the amount of ac.d used from the
electrolyte will cause the gravity to drop 100 to 150 points. TW
rivity of a fully charged cell is 1.275, it wJI, at the end of
the gravi y depending on the type of cell.

^e tuer" should never be allowed to drop below this point, bul
should i-ediatcly^aced on charge. ^ ^ ^ ^ ^ ^

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- -ml* n^

efficiency; but for vehicle use. scracx m ^
very essential, and the attempt ai i. — V -^
ments is accountable for the T*nc t.tth- at

cially employed for the pxyj* r
form mentioned, into wi^- ^ <am~ L
pressed, has been adopted

Sulphating. The eam-r* tf :
sulphate, which take* pb~ Glnjl . /

*&■- ic

•**•*•- in

ric
^.- ted

ua+ .IV.

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20 ELECTRIC AUTOMOBILES

becomes hard and white, and the presence of white spots on the plates
is an indication that the cells have been neglected. In this condition,
the plates have lost their porosity to a considerable extent and it is
correspondingly more difficult to force the charging current through
the active material. This is the abnormal condition usually referred
to as sulphated.

Continued and persistent charging at a low rate will restore prac-
tically any condition of sulphate, the time necessary being in propor-
tion to the degree to which the condition has been allowed to extend.
It is entirely a question of time, since a higher rate will only produce
gassing and high temperature, the low rate being all that the cells in
this condition are capable of using.

Time Necessary to Restore a Sulphated Battery, The additional
length of time necessary to restore a sulphated battery is illustrated
by the following test:

Preventing Sulphating. In ordinary charging, there is usually
not sufficient time to continue the charge until absolutely all the
sulphate has been converted. To prevent the small amount of
sulphate remaining from increasing and getting hard, an equalizing
charge should be given at frequent intervals. Some makers recom-
mend doing this once a week, others every fortnight, and still others
once a month. This equalizing charge is an extra long charge at a
low rate, whereby no more current than can be absorbed by the
amount of sulphate remaining is passed through the cells.

A battery was charged to the maximum, and the gravity regulated to exact ly
1.275, with the electrolyte just one-half inch above the tops of the plates, this
height being carefully marked. The battery was then discharged and recharged
to 1.275 at the normal rate in each case. The specific gravity changed from
1 .265 to 1 .275 during the last hour and a half of the charge. During the following
twelve weeks the battery was charged and discharged daily, each charge being
only to 1.265, thus leaving 10 points of acid still in the plate. At the end of the
twelve weeks the charge was continued, to determine the time required to regain
the 10 points and thus restore the specific gravity to the original 1.275. Eleven
hours were needed, as compared with the hour and a half needed at first.

The test further illustrates why it is necessary to give a battery
an occasional overcharge, or equalizing charge, to prevent it becom-
ing sulphated. Had the battery in question been charged daily to its
maximum of 1.275 and discharged to the same extent during the
twelve weeks, nine and a half hours of the last charge would have been
s.ived. It is neither necessary nor desirable, however, to carry every

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ELECTRIC AUTOMOBILES 21

charge to its absolute maximum. The weekly equalizing charge is
better practice.

Restoring a Sulphated Battery. It has become more or less
common to suspect the battery of being sulphated every time it fails
to give the mileage the user thinks it should give on an electric vehicle,
or to have the capacity for starting that, in the driver's estimation, it
should have, on a gasoline car. But if the sediment has not been
allowed to reach the bottom of the plates, and if the level of the
electrolyte over the plates has been properly maintained by replacing
evaporation with distilled water, the battery can be sulphated only
because it has not been properly charged, or because acid has been
added to the electrolyte. An individual cell may become sulphated
through an internal short-circuit, or by drying out as might be caused
by failure to replace evaporation with water, or failure to properly
replace a broken jar.

Sulphate Tests. To determine whether a battery is sulphated
when it is known that it does not require cleaning, it is advisable to
remove it from the car, give it the ordinary equalizing charge, and
discharge it at the normal rate. If it gives its rated capacity, the
reason for short mileage should be looked for elsewhere in the electric
vehicle, or in the other essentials of the starting and lighting system
on a gasoline car. (The removal of the battery refers to an electric
vehicle and not to a starting and lighting battery.) If the rated
capacity is not obtained on this discharge, recharge in the usual way.
When the battery is considered fully charged, take and record a
hydrometer reading of each cell and the temperature of one cell.
Charge the battery at a rate as near one-half its normal rate as the
charging apparatus will permit. If the temperature reaches 110° F.,
reduce the current or temporarily interrupt the charge not to exceed
this temperature.

Treatment for Sulphates. A battery is sulphated only when acid
is retained in the plates. When the specific .gravity of the electrolyte
has reached a maximum, it shows that there is no more sulphate to be
acted upon, since during the charge the electrolyte receives acid from
no other source. Hydrometer readings should be recorded at intervals
sufficiently frequent (four to six hours apart) to determine if the
specific gravity is rising or if it has reached its maximum. Continue
the charge, recording the readings, until there has been no further rise

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ELECTRIC AUTOMOBILES

IfiE

flflE

ZDE

8fl =

♦ ir
♦ii

♦13
♦14
♦tt
♦If

-♦ 7

♦ <

♦ 3

- I

in any cell during a period of at least twelve hours. Maintain the level
of the electrolyte at a constant height by adding pure water after each
reading with the hydrometer. (If water were added just before taking

hydrometer readings, the water would
not have time to mix properly with
the electrolyte.) Hydrometer read-
ings should be corrected for any con-
siderable change in temperature dur-
ing the charge in accordance with the
scale shown in Fig. 9. Should the
gravity rise above 1.300 in any cell,
draw off its electrolyte down to the
top of the plates and put in as much
distilled water as possible without
overflowing. Continue the charge,
and if the gravity again goes above
1.300, it shows that acid has been
added during the previous operation
of the battery . The electrolyte should
then be emptied out, replaced with
pure water, and the charge continued.
The treatment can only be considered
complete when there has been no rise
in the gravity of any cell during a
period of at least twelve hours of
continuous charging.

Upon completion of the treatment,
the specific gravity of the electrolyte
should be adjusted to its proper value
of 1.270 to 1.280, using distilled water
or 1.300 acid as may be necessary.
In cases where one or more individual
cells have become sulphated, while the
balance of the battery is in good con-
dition, it is better to remove such cells anc> treat them individually.
The active material of sulphated negative plates is generally of light
color and either hard and dense or granular and gritty, being easily
disintegrated. It is the negative plates which require the prolonged

lfi:

M =

Fig. 9. Fahrenheit Thermometer with
Special Temperature Scale for Cor-
recting Density of Electrolyte

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ELECTRIC AUTOMOBILES 23

charge necessary to restore a suphated battery. Sulphated positives,
unless physically disintegrated or badly buckled, are but little changed
in appearance and can be restored to operative condition, although
their life will not be as great as if they had not been subjected
to this abuse. Sulphated plates of either type should be handled as
little as possible. By strictly following the simple rules of operation
given in connection with charging and discharging the battery, the
expense and trouble inseparable from restoring a sulphated battery
may be avoided.

Capacity of Cell. Depends upon Plate Area. The ampere-hour
capacity of a cell, or the amount of current which it is capable of
absorbing and reproducing through the medium of the chemical
processes described, is determined by the area of its plates. This area

Fig. 10. Complete Battery of Cells for Pleasure Car

depends upon the area of the single plate as well as upon the number of
plates the cell contains. It is customary to make both outside plates
in a cell negatives, so that the cell contains an odd number of plates
and its capacity is fixed by the number of positives. The ampere-
hour capacity of a battery, the cells of which are all connected in one
series, is the same as that of a single cell in the series; just as, in con-
necting up dry cells or other primary batteries in series, the current
output is always that of a single cell, while the voltage of the current
increases with the number of cells thus connected.

Its capacity, in turrr, limits the safe rate at which its output may
be discharged. This area may be large or small, but, as high capacity
and discharge rate are desirable, and as the battery space in a vehicle
is limited, the makers must use the greatest possible plate area within

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24 ELECTRIC AUTOMOBILES

limits of good mechanical construction that may be employed in a
container of given dimensions.

Depends upon Amount of Active Material. The ampere-hour
capacity of a plate depends upon the amount of available active
material it contains. Since acid and lead combine with each other
in a definite proportion in producing current, it might seem possible
to have acid and lead in a cell in such quantities that both would
be completely exhausted. Toward the end of the discharge, however,
the electrolyte would be so weak that it would not be capable of pro-
ducing current at a sufficient rate for any practical purpose. For this
reason it is necessary to have acid in the electrolyte in excess of the
amount actually used in the plates during discharge. Similarly, if
all the active material were combined with acid, the plates would lose
their porosity and conductivity, and an excess of lead active material
would be provided.

A complete assemblage of cells for a pleasure car is shown in
Fig. 10.

CONSTRUCTION AND EFFICIENCY OF CELL PLATES

Thick vs. Thin Plates. The idea that a thick plate would give
longer battery life than a thin one was one of the numerous causes
of the low efficiency of the early electric vehicles. The weight was
greatly increased and the capacity of the cell reduced in the same
proportion, and it was only with a considerable reduction in the
thickness of the plates with a correspondingly greater number per
cell that practical mileages were reached. The dimensions adopted
have been adhered to for a number of years and have become recog-
nized as standard. However, in the past few years a thin-plate
type of battery has been developed very successfully. A belief still
prevails to some extent, however, that the life of the standard cells
is longer, since it will naturally take longer for the thicker layer of
active material to slough away from its supporting grid. But storage-
battery capacity is dependent, among other things, upon the surface
of the active material presented to the electrolyte. Conversely, the
rapidity with which this material wears away depends upon the den-
sity of the current drawn from it. Considering the 35-ampere-hour
capacity, 4-hour discharge-rate cell composed of 1 1 thick plates, there
is a discharge of 7 amperes per positive plate. If, as is now frequently

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ELECTRIC AUTOMOBILES 25

done, 15 plates are employed in the same size of jar, the discharge per
positive plate is only 5 amperes. Therefore, if there is more material
to slough away in the thick plates, there is, on the other hand, but
five-sevenths of the sloughing effect on the thin ones. But there is a
still more important consideration . The active material lying between
the two plate surfaces is not of the same value as the surfaces them-
selves, because of mechanical, as well as of electrical, reasons. Once
the surfaces disintegrate, the bulk of material behind them falls away
more rapidly and gives poorer efficiency.

Another advantage of thin plates is the reduced heating effect
due to high discharge rates on hills or poor roads, such discharges
being handled better by improved acid diffusion and the larger
percentage of conducting grid to active material. If vehicles oper-
ated continuously at full speed without grades or stops, this would
have little bearing on the question; but as one of the chief functions
of the electric is its easy and frequent starting ability, it is evident
that the high currents necessary for this purpose are handled to
better advantage by many thin plates than by a few thick ones.

Measurement of Capacity. The standard unit for measuring
capacity of a storage cell is the ampere hour, which means a current
of one ampere flowing for a period of one hour. When the capacity
of a cell is stated as a certain number of ampere hours, this indicates
that the cell will deliver 1 ampere of current for the period given, 2
amperes for one-half that period, etc. This does not mean, however,
that this progression may be carried to the other limit, as th£ effi-
ciency of the cell falls away as the discharge rate becomes greater.
In other words, while a 100-ampere-hour cell will produce 1 ampere
for 100 hours, 2 amperes for 50 hours, 4 amperes for 25 hours, and
so on in the same proportion, it will be found, as the rate of discharge
increases, that the capacity will fall off, the same cell not being able
to deliver 25 amperes for four hours, or 50 amperes for two hours.

In former years, the capacities of all lead-plate cells for vehicle
use were based on a four-hour rate of discharge. Thus a 140-
ampere-hour cell was guaranteed to discharge 35 amperes for four
hours. Since the introduction and more or less general use of thin-
ner plates, many makes are sold on a basis of a 5-, 5J-, and even a
6-hour rate, so that 35 and even 37 or 38 amperes are guaranteed
for five hours or more from a battery occupying no greater space.

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26 ELECTRIC AUTOMOBILES

Rate of Discharge. Since the current is produced by the action
of sulphuric acid combining with lead in the plates, the rate at which
the acid can penetrate the active material determines the maximum
rate at which current can be produced. For instance, if the same
amount of material used in making a nine-plate cell were employed
in but two plates, one positive and one negative, the ampere-hour
capacity at a sufficiently low discharge rate would be just the same as
if this material were divided into four positives and five negatives.
At ordinary rates of discharge, however, the acid could not penetrate
the active material of such a thick plate fast enough to maintain the
discharge rate for the required time. If these same plates were split
into thinner plates, the acid could much more readily get to that
portion of the material which in the thick plates was farther removed
from the surface, and current could therefore be produced more
rapidly. It is, consequently, apparent that the material can be
divided into thinner and thinner plates to maintain an increased rate
of discharge. But the thinner the plates, the shorter the life of the
cell under ordinary conditions of service, as has been explained just
previously.

Safe Discharge Point for Plates. The point to which the cell
can be safely discharged is not limited by the period during which
it is used so much as by the voltage of the cell itself. The discharge
should never be carried so far that the voltage falls below 1.8 volts
per cell, while the voltage when charged should be 2.2 volts per cell,
or slightly in excess of this, especially just after the completion of
the charge. The majority of vehicle batteries are designed to have
a normal eight-hour rate of discharge, and their capacity, for pleas-
ure cars, seldom exceeds 180 ampere hours. Such cells will dis-
charge 10 amperes for a period of 10 hours without falling below 1.8
volts, provided conditions of charging and discharging have been
favorable, and the battery is otherwise in good condition. During
the discharge the sulphuric acid, as indicated by the chemical equa-
tion already given, is partially converted into water and lead sul-
phate, and when carried to extremes, the electrolyte would be
practically all water, and the voltage would fall to about 1.46,
virtually ruining the cells. However, the sulphion, or S0 8 , is only
abstracted from the electrolyte where it is in contact with the plates.
As it is removed, the density of the fluid decreases, and a circulation

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is set up, thus permitting fresh acid to take the place of that exhausted.
The chemical action is naturally most rapid in the minute pores of the
plates where circulation is most difficult, so that when the cell is
allowed to stand idle, the fresh electrolyte penetrates the plates and
there is a correspondingly marked rise in the voltage of the cell. This
explains what is known as the recuperative power of the storage cell,
in which the voltage will rise very soon after breaking the circuit,
even in a cell that has been almost entirely discharged.

Theoretically, we should be able to take from the storage cell
the same amount of electricity as is put into it, but this is not the

nrge '

§ PIO

7ft

¥>

'f,

■f/<

i §0

''A

Discharge

/ AO

SAJ

t.tfU

tTD

160

/Impure Hours

Fig. 11.

50 HX> /50 tOO Z50 300 350 400

Relation between State of Charge and F..M.F.
in I^cad Storage Cell

case. The cell absorbs an amount of electric energy, as represented
by the following equation :

W=EXQ

in which W equals the energy expressed in watt hours, E is the
terminal e.m.f., or potential, in volts impressed upon the battery, and
Q is the quantity of electricity in ampere hours absorbed by the
battery. The loss of energy incidental to the operation of the
battery is manifested in the reduction of the terminal e.m.f. on
discharge, or the difference between the potential required to charge
it and that at which it discharges. Characteristic curves of a lead
cell showing the voltage on charge and discharge and the relation
the voltage bears to the state of charge is given in Fig. 11. The loss
of energy due to the drop in voltage is represented by the cross-

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28 ELECTRIC AUTOMOBILES

hatched area between the two curves and shows how much more
current must be put into the cell than can be taken out of it.

Life of the Cell. In view of the extremely severe nature of
the service it is to be employed for, when designed for electric vehicle
use, it will be evident that there are numerous requirements that
must be met by the successful storage cell made for this purpose.
The chief difficulty is to be found in the fact that the conditions
under which the cell must work are directly opposed to the successful
maintenance of its most necessary features. For instance, to be
efficient, the plates must be as porous as possible, in order to permit
of a free circulation of the electrolyte through the active material.
On the other hand, they must be made as durable as a board, in order
to withstand the effects of jolting and vibration. The arrangement
of the grid and the active material should be such that the current
may flow equally through all parts of the completed electrode. This
requires that the electrical resistance from any two points in the
plate should be the same to the connecting lug, something that is
naturally impossible of achievement and is only approximated as
closely as conditions will permit.

Provisions for Expansion and Contraction of Plates. The con-
struction of the grid must be such as to allow of its expansion and
subsequent contraction under the heat of charging and discharging,
without the expulsion of the active material from the containing
pockets, and without causing it to crack and fall to the bottom of
the cell. This is doubtless the most prolific single source of storage-
battery troubles, and the fact that it is one of the most difficult
requirements to be met in the manufacture of the cell is responsible
for the maker's injunction never to charge at such a rate that the
temperature will be greater than 110° F., cells in the center of a group
being taken as a guide. Unceasing investigation and experiment
extending over many years have been devoted to an attempt to
solve this problem without finding an adequate remedy, as the
expansion during the process of formation, or charging, as it is
generally called, is very great. In the Edison cell, in which an
alkaline solution is employed in connection with iron and nickel
electrodes, the active material is placed in small steel tubes and
pockets under great pressure, and the latter are then similarly
fastened in the grids.

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ELECTRIC AUTOMOBILES 29

The method of fastening the active material in the grids is really
the crux of the problem, as it must not alone be mechanically sound,
but must also make good electrical connection, if the battery is to
be efficient. Expansion causes the active material to loosen and
become separated from its metal foundation, and as this progresses,
the electrical contact becomes poorer and the efficiency of the cell
decreases. The ultimate loss of contact places the cell out of com-
mission. There are further requirements in addition to those men-

Fig. 12. Bijur High-Duty Battery Plate

tioned, such as the necessity of making the grid proof against corro-
sion. This is likewise a practical impossibility, but has been over-
come to the extent of using material so proportioned that both grid
and active material will have an equal life and may be replaced
together. Local action, by which is meant the formation of an
electrical couple through differences in the material of the grid and
the active material, thus constituting a cell, or many of them, within
a cell, must likewise be avoided. Quite as important as any of the

30 ELECTRIC AUTOMOBILES

foregoing is the provision for circulation, and the active material must
be so disposed as to present the greatest possible amount of surface.

Some typical forms of grids illustrating the manner in which
these various conditions have been met by a number of different
manufacturers are shown in Fig. 1, Fig. 4, Fig. 5, and Fig. 12. A
section of a complete cell, Fig. 13, shows how its components are
assembled.

Use of Separators between Plates. In a storage cell for sta-
tionary service the plates are separated merely by allowing a certain

Hrap
Strap

Fig. 13. Part Section of Exide Storage Cell Showing Complete Assembly
Courtesy of Electric Storage Battery Company, Philadelphia

space between them, but this would obviously be out of the question
in a vehicle battery. An insulating separator is accordingly quite
as important a component of the cells as the electrodes. Very thin
sheets of corrugated wood are generally employed, with thin sheets
of perforated hard rubber placed on each side of them. These insulat-
ing unit groups exactly fill the space between adjacent plates so as to
permit of no relative movement whatever. No matter how well the
cell is made, or of what type, where lead grids are employed, disinte-
gration of the active material is constantly going on in service and
as this material is an excellent conductor it must not be permitted to
come in contact with the plates. The latter are accordingly placed

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ELECTRIC AUTOMOBILES 31

on strips of wood to raise them from the floor of the cell and to
permit the loosened active material, or sediment, to fall clear of
them. Hard-rubber ribs, integral with the jar, are also used.

Containers for the Cell. The remaining components necessary
to complete the cell consist of a suitable container for the electrolyte
and electrodes, a means of closure, provision for the escape of the gas
generated during the process of charging, and means for connecting
the cell electrically to its neighbors on either side that go to compose
the battery. The containing jars are usually made of hard rubber
and have covers of similar material which are sealed in place with
a compound specially made for the purpose and which melts at a
comparatively low temperature. The connecting lugs project through
these covers and are usually burned to straps or bars of lead. The
cover is also provided with a vent for the escape of gas, this opening
usually being closed with a soft-rubber plug, intended to be taken
out when the battery is on charge. Groups of cells, usually in fours
or multiples thereof, are held in oak cases.

TYPES OF CELLS

Qeneral Characteristics. It will be noted that there is con-
siderable difference in the appearance of the various plates illustrated
here, and it may be added that there is a corresponding difference
in their construction. Despite the almost innumerable attempts
that have been made to discover materials that would not have the
disadvantages of bulk and weight for storage-battery work, the lead-
sulphuric-acid type is still commercially supreme. Although there
are many minor variations of design and construction, there are two
general classes of lead plates employed. These are the Plants and
the Faure. In both, lead peroxide is the active material at the
positive electrode and finely divided spongy metallic lead at the
negative, one of the means of distinguishing the plates apart being
their color, the negative showing a dull gray, while the positive is red.
The plates of the Plants type consist of pure lead of relatively small
sectional area, with all exposed surfaces scored, fluted, or corrugated
in similar manner to increase the area that can be reached by the
electrolyte.

Pure lead is very soft and yielding, and it is often necessary to
supply a supporting framework of hard cast lead to lend additional

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32 ELECTRIC AUTOMOBILES

stiffness to the plates, particularly for vehicle work. These plates
and the electrolyte complete the Plants type of cell, as the active
material is directly formed electrochemically from the material of
the plates themselves by being subjected to a series of charges and
discharges. In the Faure type, a cast grid of comparatively hard lead
is employed as the foundation, and the active material is placed in the
interstices in the form of a stiff paste, the whole plate being subse-
quently subjected to considerable pressure. On this account it is
usually referred to as a pasted type of plate. The Exide cell, plates
of which have been illustrated in Figs. 4 and 5, is representative of
this class.

Only the Faure type is used for vehicle batteries as the Plants
is a "formed" plate from which the active material would be shaken
by the vibration.

Improved Forms

Nature of Improvements. The foregoing are what are known
as flat-plate types of elements, and the life of this form of battery
is usually measured in terms of the life of the positive plate, as it is
the latter which suffers most from the charging and discharging
process. It is nothing unusual for the other elements in the cell
combination to outlast the positive plate two or three times over,
new separators being installed with each renewal. Accordingly, the
problem has been to devise a type of positive plate that would equal
the negative in durability. Many forms of protective coverings
designed to prevent the active material from washing out of the
plate have been tried with varying degrees of success. Among these
have been plates built up of parallel cylindrical pencils of the active
material. While the latter did not prove a solution of the problem
in its simple form, this idea, in combination with a basic principle
originated by a French maker, served as the foundation for what is
known as the "Ironclad" Exide type. For this form, the makers
claim that the positive plate not only lasts practically as long as the
negative, but that the battery is capable of withstanding the abuse
of overcharging to a degree never before attained. The importance
of the latter in the commercial use of electric vehicles can hardly be
overestimated and is brought out in the paragraphs on "Boosting",
Part II.

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ELECTRIC AUTOMOBILES 33

Ironclad Exide Type. Positive Plate. The Ironclad Exide
positive plate consists of a grid composed of a number of parallel
vertical metal rods united integrally to horizontal
top and bottom frames, the former being provided
with the usual conducting lug for carrying the
current. Each vertical rod forms a core, which
is surrounded by a cylindrical pencil of peroxide
of lead, which is the active material. These pen-
cils are enclosed in hard-rubber tubes having a
large number of horizontal slits, which serve to
provide access, for the electrolyte, or solution, to
the active material, but are of such small dimen-
sions as to practically eliminate the washing out
of the material. Fig. 14, which shows a vertical
section of one of these composite pencils, makes
this construction clear. The outside tubes are
reinforced by leaving the exposed edge solid, i.e., p . M Vertical Seo-
without slits. Each tube is provided with two li ^ g^j™

parallel vertical ribs projecting on opposite sides
at right angles to the face of the plate. These ribs not only serve
to stiffen the tubes, but, being of hard rubber as are the tubes them-

Fig. 15. Positive Pencil Fig. 16. Assembled Exide

Showing Rib Positive Plato

selves, also act as insulating spacers, allowing the use of a flat piece of
wood veneer in place of the ribs on the wood separators in other types.

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34 ELECTRIC AUTOMOBILES

The reinforcing rib is shown by Fig. 15, which is a side view of the
tube. These rubber tubes have a certain amount of elasticity allow-
ing them to compensate for changes in volume of the active material,
owing to the expansion and contraction during charge and discharge.
A complete positive plate of this type is illustrated by Fig. 16. This
cylindrical form of tube is peculiarly well adapted to perform its
function, since no amount of expansion or contraction will tend to
alter its shape, and the internal stresses are thus kept uniform.
Another advantage is that most of the electrolyte necessary is carried
within the confines of the plate itself. This is illustrated by a com-
parison of horizontal sections of portions of the Ironclad Exide plate
and the standard Exide plate, as shown in Fig. 17.

Negative Plate. To conform to the construction of the new
positive, the negative is also modified somewhat, the upper and

Exide
Fig. 17. Comparative Sections of "Ironclad" and Standard Exide Plates

lower edges of the plates being encased in rubber vulcanized in the
plate. This eliminates the possibility of short-circuits from material
bridging across from the positive frames. The negative frames are
undercut, so that the rubber sheathing is flush and does not project
beyond the face of the plate. The thickness of this negative plate
is calculated to provide approximately the same life as the posi-
tive, thus avoiding partial renewals, which cut down the efficiency
of the cell.

Separators. The special form of the positive plates renders
unnecessary the flat perforated rubber sheet used in the standard
types of cells, the only separator employed being the wood veneer
mentioned. The greatly increased life of the new cell made it neces-
sary to employ a separator of greater durability than those in current
use and, after investigation, a special kind of wood possessing great
toughness, as well as ability to resist the action of the electrolyte to

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ELECTRIC AUTOMOBILES 35

a remarkable degree, was adopted. These separators are made
with the grain of the wood running horizontally in order not to
register with the vertical ribs on the positive plates, which would
tend to split the wood. The ^>ositive and negative plates are

Fig. 18. Pillar Type of Strap Connectors
Courtesy of Electric Storage Battery Company, Philadelphia

grouped in the customary manner, the lugs being burned directly to
the usual lead straps, except that the straps are of the pillar type,
illustrated by Fig. IS.

Improved Connectors. Mention has been previously made or
the necessity of providing the maximum conductivity in the ele-
ments of the cell as well as in the units of the battery in order to
keep its internal resistance down, as upon the latter depends its
ability to discharge its energy at a high rate, this being a valuable
characteristic for hill climbing or bad road conditions. The usual
practice has been* to employ the same alloy of lead and antimony
for connecting the cells, the latter having strips of the metal burned
to the pillars or other projections designed for receiving the inter-cell
connections. For this purpose, the makers of the Ironclad Exide
cells have brought out an improved form of connector, shown in
Fig. 19. This is known as a built-up type, consisting of thin strips
of copper, lead-covered to prevent corrosion. A number of these
strips, depending upon the cur-
rent to be carried, are laid face

t±u.cas*4

tO face, and their ends Cast into Fig. 19. Lead-Covered Copper Connecting Strip

lead-alloy terminals, a special Court " y of Electric storage Batterv Company
welding process insuring effective and permanent contact between
the flexible strips and the cast terminal. By this means, good
conductivity is obtained under all conditions of vibration and tem-
perature changes. The lead-alloy terminals are ring shaped to fit
over the pillar of the strap and are burned in place. The use of
copper gives a higher conductivity than lead alloy, while the lami-
nated structure provides a flexible, instead of a rigid, connection.

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36 ELECTRIC AUTOMOBILES

Starting Batteries. The advent of electric starting motors
on the automobile has been responsible for adding to the problems
of the storage-battery maker. As outlined in the chapters devoted
to starting and lighting, the requirements are such that the maximum
output of which the battery is capable is called for instantaneously

Fig. 20. Sectional View of Titan Cell Showing Diagonal Ribs of Active

Material to Lessen Resistance

Courtesy of Horseless Age

every time the gasoline motor is started. Any one who has cranked
a car on a very cold morning after the motor has been idle over night
will realize the greatly increased effort necessary to move the pistons,
owing to the adhesion caused by gummed, or partly frozen, lubricating
oil. Special provision is accordingly necessary to reduce the internal
resistance of the cells of the battery in order that it may deliver
its maximum output, the demand usually representing a considerable

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ELECTRIC AUTOMOBILES 37

overload. One method of attaining this is shown in the "Titan"
cell, in the positive plates of which the conductivity afforded by
the grid is greatly increased by the provision of diagonal ribs run-
ning in the general direction of the points where connection is made
to the strap, as illustrated by Fig. 20, which shows a section of the
cell. This increased conductivity tends to reduce the tendency of
the plate to buckle and force out its active material when sub-
jected to such a heavy demand for current.

In addition to the service being of such a severe nature, the
conditions under which a starting battery must operate are equally
strenuous in other respects.' Touring cars
are driven at very much higher speeds than
electric cars and frequently over rough
roads, which greatly adds to the amount
of vibration that the plates must endure.
Special provision must accordingly be made
for the reception of a greater amount of
sediment and in a manner which will pre-
vent the latter from reaching the bottom
of the plates. This takes the form of an
increased depth of electrolyte below the
elements, while the space thus allowed is

provided with an increased number of ^ 21 Gould Startinp Bat _
baffle plates, or partitions, to prevent the tory c ^ n f^ Hl * h

sediment from being washed about and

accumulating in one place. The Titan cell is an illustration of this,
and it is also shown in the Gould cell, Fig. 21, which also incorporates
the use of built-up connectors of copper and lead. Both of these
cells likewise embody an improved form of cover. They are
enclosed by two hard-rubber covers and an intermediate layer of seal-
ing compound in adhesive contact with the sides of the jar. Sleeves
of hard rubber permit of some flexibility at the pillars while still
insuring an air-tight joint with the sealing compound.

Integral with the lower cover is an expansion chamber communi-
cating with the interior of the cell and provided with a threaded cap.
In the case of the Gould cell, leakage is guarded against by the
inverted conical form of this cap, and as the battery boxes are now
made in accordance with the S. A. E. standard dimensions, they may

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38 ELECTRIC AUTOMOBILES

he placed end to end, reducing the thickness to 4£ inches in the largest
size, and permitting the battery to be suspended between the chassis
frame and the running board, concealed by an apron.

Edison Battery. Inasmuch as the Edison battery represents
the only successful attempt to make use of a reaction other than that
of the lead-sulphuric-acid couple discovered by Plante\ the inventor
of the so-called storage battery, the Edison cell is of unusual interest.
Placing this battery on the market in commercial form is said to
have involved the expenditure of more than two million dollars, as
special processes and costly machinery had to be originated for its
manufacture, while more than fifty thousand separate experiments
were made in a period of seven years before the solution of the prob-
lem itself reached the stage where manufacturing could be undertaken.
. The elements of the Edison cell consist of nickel and iron in an
alkaline solution, and, as the capacity of a storage cell depends upon
the area of the active material in contact with the electrolyte and
upon the conductivity of its members, the problem was to utilize these
materials in the form best adapted to give efficiency and durability.
Three years were devoted to this phase of the problem, after the
reaction giving promise of success had been discovered, before the
first crude cell was made.

Composition of Plates. The positive plate of the Edison cell
consists of vertical rows of thin, perforated steel tubes filled with
nickel hydrate, these tubes being supported in a steel frame somewhat
similar in appearance to a pencil-form lead grid, as will be noted by
reference to Fig. 22, which shows a positive and a negative plate com-
plete. Rows of flat, perforated steel jackets filled with iron oxide,
likewise held in a thin steel frame, compose the negative plate. The
elements are, accordingly, nickel, iron, and steel in a 21 per cent
solution of potash in. distilled water, and these elements constitute
a storage cell which differs radically in every respect from the lead-
plate type. In fact, this is the only storage cell the elements of
which are not attacked by the electrolyte when left standing in a
charged, partly-charged, or wholly-discharged condition for any
length of time. Apparently the potash acts as a preservative of all
the elements entering into the combination.

Iron oxide will be recognized as one of man's most .persistent
and ubiquitous enemies, rust. Nickel hydrate is the product of a

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ELECTRIC AUTOMOBILES 39

special electrolytic process originated by Mr. Edison. When on
charge, this iron oxide, or rust, of the cell's negative plate is con-
verted into metallic iron, while the oxygen generated passes over
to the positive plate and converts the nickel-hydrate content into
a new form of nickel oxide, previously unknown to science. The
oxidizing of the nickel hydrate causes it to expand just as the peroxide

Ffe. 22. Assembled Positive and Negative Fig. 23.- Completely Assembled

Edison Plates Edison Cell

of lead of the lead positive plate does, but there is no danger of
loosening or loss of the active material in this case, as it is held in
a rigid steel tube. The latter has numerous fine perforations to
permit access of the electrolyte, but these are so numerous that the
steel approximates wire netting or gauze.

The container is of steel welded in a special machine making
it an integral unit which cannot be opened without destroying it.

40 ELECTRIC AUTOMOBILES

Protruding through the top and surrounded by hard-rubber washers
are the two tapering terminals, and between them is the filler cap
through which the solution of potash and distilled water is introduced.
This cap acts as an automatic relief valve which allows the gas gen-
erated to escape but prevents the entrance of air. The cells are con-
nected by nickel-plated solid copper strips fastened to the threaded
terminals with nuts so that the units of a battery may be taken apart
readily, Fig. 23. The cells are fitted in wooden trays and tightly
clamped in place, Fig. 24,

Advantages and Disadvantages. Chief among the advantages of
the Edison battery for commercial-vehicle use are its long life and

Fig. 24. Tray of Four A -4 Ivlison Cells

its ability to withstand what would be considered flagrant abuse,
if applied to a lead battery. It may be charged or discharged at
any rate within the current-carrying capacity of its connections,
allowed to stand either charged or wholly discharged for any length
of time, without injury, and in other ways subjected to electrical
abuse which would ruin a lead-plate battery in a comparatively short
time. As evidence of its durability and continued electrical efficiency
even under such treatment, it is guaranteed for four years' use.

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ELECTRIC AUTOMOBILES

While the voltage of each cell is but 1.25 volts as compared with
2 volts for the lead cell, its construction is so much lighter that there
is a saving in weight in battery of Edison cells when compared with a

2LO

—9

/JB

Charae

""~

f.6

Discharge

t.o

Z 3 4 S 6

Moors

Fig. 25. Charge and Discharge Curves for Edison Cell

lead battery of the same voltage and capacity, despite the added
number of the former necessary to give the same potential. Fig. 25
illustrates the charge and discharge curve.

Size of Battery. The voltage of the vehicle circuit has a two-
fold bearing upon the latter's efficiency. On one hand, there is the
factor of efficient utilization of the energy and, on the other, of
the charging efficiency of the battery. Thus there is a constant
loss at both ends which accounts for the abandonment of 24- and
30-volt batteries which were common in electric cars of the pleasure
type about. 1905. The most common voltage of direct -current
lighting and power circuits is 110. To charge less than 42 or 44
lead cells or 60 alkaline cells means a loss of current in the rheo-
stat, this loss increasing as the number of cells decreases. This
makes the vehicle owner pay for many more kilowatt hours than
he receives in the form of energy in the battery. With a 30-cell
lead battery, for example, charging on 110 volts, one-third of the
current paid for by the user is wasted, so that it is now customary
to employ 42- or 44-cell batteries on most of the heavy-type commer-
cial vehicles, though practice in this respect varies on pleasure cars
according to their weight, the range usually being from 30 to 42
cells, the former number being used for light three-passenger vehicles
and the 40- and 42-cell batteries in broughams and limousines.
With alternating currents this objection does not hold good.

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42 ELECTRIC AUTOMOBILES

THE MOTOR

Quite in contrast with that of the gasoline car, the motor of an
electric vehicle is probably responsible for less of the troubles encoun-
tered than any other one of the essential- components. While the
relative amount of attention it requires at the hands of the owner
of the vehicle is small, a knowledge of its construction and working
will be found of value in the operation and maintenance of the car.
It is here that the energy held in reserve in the storage battery is con-
verted into the mechanical power necessary to move the vehicle.
The reason for the small amount of attention required is apparent in
the small number of parts as well as their great simplicity, though
the great amount of attention that has been devoted to the develop-
ment of the electric motor over a long period of years is largely
responsible for the elimination of the numerous shortcomings of the
earlier types.

Essentials of Motor. The motor consists of a field, an armature
suitably mounted on bearings so that jt may be revolved in that field,
a, frame, a commutator, and brushes. The terra field is the generally
accepted abbreviation for magnetic field, which is the zone of influ-
ence exerted by a magnet, and is referred to in terms of its "lines of
force". A common horseshoe magnet, technically known as a
permanent wiagnet, will attract to its ends or poles particles of iron
and steel placed within a certain distance of it. The space bounded
by the poles of the magnet and the limits to which its attraction
reaches, is known as its field. With reference to electric motors and
generators, the word is employed to designate the magnets and pole
pieces which serve to create this field, rather than the scope of mag-
netic attraction itself, and it is used to embrace all of them, regard-
less of their number.

Principle of Rotation. The fundamental principle upon which
the functioning of all apparatus of this type is based is to be found
in the fact that when a current of electricity is passed through a coil
of wire surrounding a bar or other form of iron or steel, the metal
becomes magnetic in proportion to the number of turns in the coil
of wire and the strength of the current employed. Every magnet
consists of a north and a south pole, and like poles repel while unlike
poles attract one another. In other words, if two small common mag-
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ELECTRIC AUTOMOBILES 43

nets are placed on a table with their like poles, i.e., north to north
and south to south, facing one another, the magnets as a whole will
tend to repel one another, and were they sufficiently powerful, would
actually recede from the common center until the limits of their field
were reached. By reversing the polarity of the opposing ends of
the magnets, they w T ould then tend to be drawn to one another until
the poles butted. This, in brief, sums up the philosophy of the
electric motor.

In order to amplify the power, a large number of magnets are
employed; and in order that the energy thus developed may be
utilized, one group of magnets is made stationary while the other
group is free to revolve. In these two groups will be recognized
respectively the field and the armature of the motor, and each magnet
of the groups is of the type known as electromagnets, so termed be-
cause they are magnetic only while a current is passing through their
exciting coils. Those of the field may be distinguished as they take
the form of short thick spokes radiating from the rim or frame toward
the center. They thus surround the space in which the armature
revolves, and are further provided with what are known as pole pieces
in order to fill as much of the space with iron as is possible. . As
already mentioned, the field of a magnet is most powerful in close
proximity to it and the armature will be seen to run as closely to the
faces of the pole pieces as good design and construction will permit.

Now it will be remembered that the direction in which the cur-
rent of electricity is sent through the exciting coil determines the
polarity of the resulting magnet. If, with the current traveling round
the coil in one direction, the right-hand end of a bar becomes of north
polarity and the left-hand end of south polarity, it will be evident
that, by reversing the direction of current flow, there will be a cor-
responding change in the location of the poles. Coming back to
practice, in which one set of magnets — the field — is held stationary,
while the other may revolve, it will be apparent that as each of the
armature magnets approaches a field magnet by virtue of the attrac-
tion between them, the motion will tend to accelerate up to the point
where they are opposite, but when the moving magnet passes by,
the attraction which still exists will tend to stop the rotation. It is
clear, therefore, that, to bring about the desired rotation of the arma-
ture some device must be used to reverse the direction of the current

44 ELECTRIC AUTOMOBILES

in each electromagnet when it has reached a point opposite the field
magnet which is attracting it so that the resulting opposite polarity
may develop a repulsion which will carry the armature in the same
direction. This is just where the function of the commutator and
the brushes comes in. The brushes serve to lead the current to the
circular group of copper bars which forms the commutator, without
retarding the rotation of the armature. Each section of the com-
mutator is insulated from its neighbors and as the brushes touch
opposite sections simultaneously the rotation makes the current enter
the armature coils first in one and then in the opposite direction,
through successive sections of the commutator, the current being
reversed and the polarity of the field magnets being changed for each
new position.

The Armature. The foundation of the armature consists of a
cylinder built up of laminations of iron, or punchings, with recesses
cut into their circumferences to receive the coils of wire, or windings,
each one of which converts the particular section of the core that it
surrounds into a powerful electromagnet when the current is passing.
All the wire employed is strongly insulated, not only to protect neigh-
boring turns from one another, but each winding is also well insulated
from its foundation, whether this be the armature or a field core.
If this precaution were not taken, short circuits or grounds would
occur. The former term is really self-defining as it shows that the
current instead of passing round the entire coil or circuit intended,
would choose the shorter path thus accidentally provided. A ground,
on the other hand, is caused where non-insulated portions of two
different wires carrying a current come in contact with the same or
a connecting piece of metal, or other conducting medium. This
opens up a path of practically zero resistance for the current, thus
diverting it entirely from the path it should follow if its energy were
to be utilized.

Both short circuits and grounds are things with which the owner
of the electric vehicle will have to become familiar to a greater or
less extent in caring for the battery of his car, as well as the remainder
of its electrical equipment, so that their nature has been explained
in detail. While both cause similar results, they are not interchange-
able terms and are employed to convey the distinction mentioned.
In other words, a ground may be a short circuit, but a short circuit

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ELECTRIC AUTOMOBILES 45

is not always a ground, as the latter implies the diversion of the cur-
rent through some normally unused conducting medium, while the
short-circuit signifies a breakdown of the insulation of the wiring
or allied appurtenances that permits of the return of the current after
having traversed but a fraction of the path intended for it. Either
trouble naturally places the piece of apparatus in which the break
occurs out of running order until the defect is remedied. In view
of their nature, grounds are usually much more difficult to locate than
shott-circuits. Some of their further causes and results are men-
tioned in the chapter devoted to the care of the batteries, also that on
the wiring.

Capacity for Overloads. It is this capacity of the motor to stand
excessive overloads that fits in with the requirements of the road,
for it must be borne in mind that the amount of power required to
keep a vehicle rolling after it is once started is very small as com-
pared with the pull necessary to start it, or to accelerate its speed.
The total amount of energy required is in direct proportion to the total
weight, and to the square of the velocity.

Motor Stands 500 Per Cent Overload. The pull, or torque of the
motor as it is called, must be very heavy at starting, particularly
when on an upgrade, and also for mounting inclines. For this
reason, the motor employed is of a type capable of standing for short
periods as much as 500 per cent in excess of its normal rated capacity.
It will be apparent that this converts the 2J-horsepower motor into
one of 12 \ horsepower in cases of emergency, without increasing
its current consumption under the ordinary conditions of load at
which the greater part of its service is rendered, such as in running
on the level or ascending ordinary inclines. The available amount
of power being so closely restricted by the capacity of the battery,
it will be manifest that this is a most important provision, and as the
average layman talks in terms of horsepower without adequately
comprehending the meaning of the latter, electric vehicle makers
have found it expedient to omit any mention of this factor. The
electric not only is not intended to be capable of the speeds of the
gasoline car, but it does not require such an excessive amount of
reserve power as it has become customary for the manufacturer to
provide on the latter type.

Under usual conditions of running, the average gasoline machine

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46 ELECTRIC AUTOMOBILES

does not employ more than a small fraction of the available power
of its motor and, in consequence, is seldom being operated at
what is technically termed its critical speed, that is, the speed at
which it is most efficient, and therefore most economical. In the
case of the majority of gasoline cars, this critical speed is from 25 to
30 miles an hour, or even higher, while for the average electric car
it is from 10 to 15 miles an hour, a speed which corresponds so
nearly with the usual speed on the road that the economy of the
electric is very great.

Parts of Motor. The foregoing description of the electric
motor for automobile use will be clear upon reference to Fig. 20,

Fig. 26. Parts of Typical Electric Vehicle Motor

which represents a largely used standard type. In the foreground
is shown the armature, at the left hand of which is shown the com-
mutator. The coils of wire on the armature run parallel to its
length, but in order to save them from injury they are protected by
a covering and this is in turn held on by the circular bands shown,
which prevent any tendency of the heavy coils to fly out of their slots
owing to the effect of centrifugal force. At the commutator end of
the armature will be seen one of the annular ball bearings upon which
it runs. This is the most advanced type of anti-friction bearing
extant, and while its first cost is correspondingly high, its use is justi-
fied by the great power saving accomplishment as well as theextremely
small need for attention that it involves. These bearings consist of
two parallel races and a number of very accurately dimensioned
balls distributed at equal distances around the circle by means of a

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ELECTRIC AUTOMOBILES 47

bronze spacer. Only the very finest materials and the most accurate
workmanship are permissible in successful bearings of this type.
They are generally employed in electric vehicles, and a further
reference is made to them in connection with transmission design.

Directly back of the armature is seen the frame, and from the
description, the field coils and the pole pieces will be readily recog-
nizable. The great amount of attention that has been devoted to
making the motor as compact as possible will be evident from the
mounting of its accessories. It will be seen that the housings are
designed to carry both the bearings and the brushes, the latter being
attached to the inner face of the cover plate shown at the right. The
parts shown in the illustration comprise the motor complete, even
including the cap screws necessary to assemble it.

Motor Speeds. Types of Motor Windings. The speed of elec-
tric vehicles is a most elusive quantity to the uninitiated, prin-
cipally because the characteristics of the series-wound motor
employed are not commonly understood by the layman. The series
type of motor is one in which the windings of the armature and field
are connected in scries, i. e., so that the entire current fed to the
motor passes through both of its elements consecutively, so to speak.
In a shunt-wound motor the field is in multiple with the armature,
so that, while the entire current passes through the latter, the
amount taken by the field is always proportioned to that required
by the armature for the load it happens to be carrying. As this
type of motor is designed for a constant speed, it is not an economical
motor to use on the electric vehicle owing to the wide fluctu-
ation of both speed and load imposed, so that its employment is
comparatively rare in this field. A compound-wound motor is one
having both series and shunt-coil windings on the fields. Since
most commercial motors for driving machinery, elevators, and the
like are of the constant-speed, compound-wound type, there is a
general impression that the electric car should have a certain nearly
constant speed for all road conditions.

Advantages of Series-Wound Motor. But in the series-wound
motor, the speed varies inversely as the power produced. In other
words, its torque, or pulling power, is highest at low speeds, which
is just the requirement demanded in starting or pulling through
heavy roads. This type cannot be employed for ordinary com-

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48 ELECTRIC AUTOMOBILES

mercial use, since it will instantly "run away" or race upon the load
being released, but it can be employed to advantage on vehicles and
in railway service because it is never disconnected from the load.
"Load" in this case refers to the effort required to move the vehicles
rather than the live load. Series motors are employed on the
electric car because of their higher efficiency, which is of prime
importance, since the object is to produce the greatest amount of
useful energy from a given and limited amount of potential energy
stored in the battery. Just the opposite of the gasoline engine, the
chief characteristic of the series-type electric motor is the develop-
ment of increased power with a decrease in the speed. Therefore,
as the vehicle requires greater power for bad roads or grades, it
slows down automatically and in a fixed relation to the power
demanded.

High-Speed Singh Motor Present Practice, Opinion and prac-
tice are divided on the subject of motor speeds. The higher-speed
motors are more efficient, are better for grades and starting, but
mechanical limitations frequently make them undesirable. Where
formerly motor speeds ranged from 650 to 1100 r.p.m., modern
practice favors higher r.p.m. rates, ranging from 1000 to 2000.
Normal speeds under 1000 are not satisfactory for most conditions,
the use of a low-speed type of motor being one of the causes of the
low efficiency of the earlier electric cars. Another reason was the
employment of two motors on comparatively light cars. This had
a certain advantage in eliminating the differential, but its electrical
efficiency was very low. Modern practice does not sanction the
employment of more than one motor on even the heaviest of pleasure
cars and on commercial vehicles up to 3- or 5-ton capacity. Beyond
that point practice varies somewhat, some makers employing two
driving units on the ground that no differential is needed, that
starting torque is bettered by connecting the armature in series,
and that damage to one motor will still permit the vehicle to travel.
These advantages are more than offset by the higher efficiency
possible in a single and larger electric motor, beside the benefits
derived from the saving in weight of the'inotor and from the ability
of the manufacturer to combine the two speed reductions necessary
with two motors into one. This avoids some power loss in trans-
mission from the motor to the driving wheels.

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ELECTRIC AUTOMOBILES • 49

THE TRANSMISSION

Similarity to Gasoline Practice. The types of power trans-
mission on the electric vehicle have been the same as on the gasoline
car except that the order of their application has been chronologically
reversed. The latter started in generally as a chain-driven machine,
and quite a number of years elapsed before any other method of
transmitting the power to the rear wheels was attempted. The
electric, on the other hand, began as a gear-driven car, as the practice
of direct-connecting electrical generators and power units, which
first assumed a strong vogue shortly prior to the advent of the
electric automobile, was taken as a precedent. From the point
of view of operating conditions, there is considerable similarity
between the gasoline and the electric machine as far as its power
transmitting system is concerned.

Usual Gear Reduction. Owing to weight and space limitations,
the size of the motor is correspondingly limited, and it is accordingly
necessary to employ high initial rotative speeds, i. e., a very high-
speed motor is essential in both cases, while the starting torque or
pull must likewise be very strong in order to enable the vehicle to get
under way quickly and to start readily on grades. This necessitated
gearing down to a very great extent, the usual ratio on the majority
of the electric vehicles being 10 to 1, i.e., for every ten revolutions
of the motor, the road wheels make but one turn. In order to accom-
plish such a reduction without employing gear wheels of a prohibitive
diameter, it was necessary to bring about this lowering of the motor
speed by means of two steps, or a double train of gears. Spur, or
plain straight-tooth, gears were employed at first, and proved to be
not only noisy, but very wasteful of power.

They were accordingly replaced by chains in many instances,
and by gears of special types, such as the herringbone reducing gears
of the Waverley. In some instances, such as the light Baker runabout
placed on the market several years ago, it was found possible to drive
directly from the motor to the rear axle through the medium of a
single chain, but with this exception the custom of employing two
distinct reductions of speed was generally followed up to a year or
two ago. While there were several variations in the manner of
accomplishing this, the general principle was practically the same

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50 ELECTRIC AUTOMOBILES

in every instance, a single chain being taken from the end of the
armature shaft of the motor to a countershaft Extending clear across
the car and having sprockets at each end. The reduction in speed
from the motor to the countershaft was usually about five to one, and a
similar second reduction was carried out by means of small sprockets
on the ends of the countershaft, and large ones on the driving wheels.
A third class of transmission consists of a combination of gearing and
chain drive, such as were used on the earlier models of the Woods,
and the Waverley electrics, the first reduction of which is a silent
chain.

Chain Driver* During the past few years, practice in the electric
field has closely followed that of gasoline car transmission design,

Fig. 27. Gear Type of Transmission

where the final drive is concerned, and in some cases anticipated it.
But for the advent of several low-priced electric cars, some of which
have perpetuated the single-chain drive — using a roller-type chain
and sprockets as the second step in the reduction — this form would
have practically disappeared. It is efficient and reliable, but not
as clean and sightly as the shaft type, though this objection may
be readily overcome by enclosing the chain. Economy in initial
cost is one of its chief advantages and, in the case of cars which are
sold at a very low figure, this is naturally of paramount impor-
tance.

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ELECTRIC AUTOMOBILES 51

Gear Drive. The self-contained unit shown in Fig. 27 is an
illustration of what might be termed an instance of reducing the
power plant and final drive to the last degree of compactness. Refer-
ing to the figure it will be noticed that the usual type of motor is
mounted on a forward extension of the rear axle, the first step in
the speed reduction being a pair of herringbone gears. Apart from
this, it is practically a replica of gasoline car practice, as the axle is
of the full floating type commonly employed on the latter, the second

Fig. 28. Well-Designed Unit of the Shaft-Driven Type
with Bevel-Gear Rear Axle

speed consisting of the usual bevel drive, except that the propeller
shaft is only a few inches long and consequently does not require
any universal joints. A somewhat similar type of transmis-
sion is employed on the Broc electrics. A full floating type
of axle with shaft drive is also a feature of the Borland, this
form taking its name from the fact that the two driving shafts
are not rigidly fastened at either end — either the differential or
the driving-wheel end — the power being transmitted through a
square-ended section of the shaft floating in the differential and a
jaw or similar type of clutch at the wheel, the entire weight of the

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52 ELECTRIC AUTOMOBILES

car being carried by the tubes or axle housing. An example of a
single reduction-shaft drive is to be found in the Century, using a
Timken bevel-gear rear axle.

An equally compact form which gives a better weight distribu-
tion is the drive illustrated in Fig. 28. This bears a very strong
resemblance to the driving unit of a well-known light gasoline car.
It is a type which affords great rigidity with a very simple con-
struction. The propeller shaft is practically a continuation of the
armature shaft, no universal joint being necessary. At its after
end this shaft meshes with a bevel gear giving a reduction of 2 to 1 ,
while a spur-pinion reduction lowers the ratio again 4 to 1, or a
total of 8 to 1 between the high-speed motor and the driving wheels.

Fig. 29. Combined Bevel and Spur Gear. Double Speed Reduction
of the Axle Shown in Fig. 28.

The arrangement of the two speed reductions in the axle is shown
by Fig. 29. These bevels have an adjustment by means of a collar
which can be loosened or tightened until a perfect adjustment is
obtained. The larger bevel is mounted on a short jackshaft carried
on ball bearings on both ends, and upon this shaft is mounted the
small spur pinion. On each side of the jackshaft is a threaded
collar which allows for the movement of this shaft either in or out,
which, in conjunction with the adjustment of the bevel gears, permits
of a perfect setting of both sets of gears. The housings consist of
tapering swaged steel tubes which extend from each side of the
differential housing through the brake housings and the wheels,
while the driving effort is taken on the combined torsion and radius
rods pivoted on saddles on the axle just inside the brake drums and
on the rear end of the motor housing.

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In this, as in all representative types of final drive on electric
pleasure cars, annular ball bearings are used throughout. One of
these bearings is shown just forward of the small bevel pinion in the
two-speed reduction axle. This is an advanced type of bearing
which the automobile has been largely responsible for developing.
It is far more costly than even the very best of plain bearings, but it
cuts friction down to a practically negligible factor, while it will also
run with a very small supply of lubricant and requires a minimum
of attention. Such bearings are now universally employed, not
alone in the electric motors of these vehicles, but also for the coun-
tershafts and wheels, and in similar locations. If the ball bearing
is not employed, the taper roller type is substituted, the latter
being very much favored for wheel bearings on both gasoline and
electric cars, owing to their ability to withstand heavy thrust as
well as radial loads.

Worm Drive. Development. What would appear to be the
ultimate development in electric car transmission, however, has been
the adoption of the worm drive; and, in taking it up so generally,
the electric vehicle manufacturers have anticipated what is bound
to come on the gasoline pleasure car in the near future, as it already
has in England to a great extent. In this adoption, the history of
the electric self-starter on the gasoline car has been repeated, in that
experiments were carried on for a number of years with little progress
apparent to the world at large, and then, within a comparatively
short time, the worm drive came into more or less general use. , In
this case, however, most of the research work was carried out in
England, and a considerable proportion of the worm drives used on
American electric cars are imported from that country. In itself,
this form of drive is not a novelty, the Hindley worm drive, made in
Philadelphia, having been employed on electric elevators for quite a
number of years. Its successful application to the automobile
represented far more of a problem than the bevel-gear type as,
unless correctly designed and machined to the highest degree of
accuracy, the friction and thrust are excessive and the resulting
efficiency is low.

Advantages of Worm-Gear Transmission. Consideration of the
fundamentals of electric vehicle design, i.e., a light high-speed
motor and a comparatively slow axle speed, will make apparent the

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54 ELECTRIC AUTOMOBILES

great desirability of the worm drive in this connection. It repre-
sents the most practical means of power transmission from a high-
speed motor direct to the rear axle by means of a single reduction.
This means saving in weight and the avoidance of the power loss
entailed through the use of the second reduction in the gear ratio
otherwise necessary. A further advantage is its silence in opera-
tion, the worm and w r orm wheel representing the closest approach to
this much-to-be-desired feature that is attainable in the transmission

of pow r er by direct metal con-
tact. While its initial cost
is as high, if not higher, than
even the best forms of double
reduction, it eliminates sev-
eral parts, and accordingly
affords a simpler form of con-
struction w r ith a more direct
transmission of the power.

• Details of Worm Drive,
Rear Axle, and Brake. The
worm is of alloy steel while
the worm w r heel is bronze, a
multiple thread of long pitch
being cut on the former
while the latter is made with
a special form of tooth, as
will be noted by the Rauch
and Lang worm shown in Fig.

I ig. 30. Ranch and Lung Worm and Gear 30. This is an American

type developed by the mak-
ers of the Rauch and Lang electrics especially for this purpose. In
both this make and the Woods electric the worm meshes with the
worm wheel on its upper side, the relation being shown by Fig. 31,
which illustrates the Rauch and Lang motor and propeller shaft in
addition. Two universal joints, one of them of the slip type to
allow for relative longitudinal movement between the motor and
rear axle, are employed. A brake is placed on the forward end of the
armature shaft, this showing in the same illustration. Fig. 32 shows
the complete Rauch and Lang motor and driving unit. A torsion

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rod, parallel with and below the propeller shaft, also serves as a
distance rod between the motor and rear axle and takes all torsional
or twisting stresses to which the axle is subjected when under power.
The forward end of this torsion rod is connected by means of a

Fig. 31. Raucb and Lang Motor, Shaft, Universal Joints, and Worm and Gear

flexible joint of the ball-and-socket type, with the top of the torsion
rod link, which in turn swivels on the rear motor yoke. The rear
end of the torsion rod is taper fitted into a nickel-steel forging, which

Fig. 32. Rauch and Lang Motor and Rear Axle Unit

sets into a vertical taper bearing in the front end of the axle housing.
The method of hanging the torsion rod leaves the rear axle housing
perfectly free to adjust itself to the relative movement of the axle
and frame due to the compression of the springs. The latter are of
the seven-eighths elliptic type, the upper and lower members of

50 ELECTRIC AUTOMOBILES

Fig. 33. Rear View of Rauch and Lang Worm Drive Chassis

which are shackled at the rear ends so that they are flatter than
usual, thus giving better riding qualities. They are held at three
points, which decreases the tendency toward lateral movement or
side sway, the driving strains being taken on the front ends of the
lower leaves. The worm and worm wheels are adjusted in perfect
alignment in assembling the unit, and the latter is housed in, so
that no adjustments can be made from the outside. Contrary to
the bevel-gear drive, which in course of time wears out of alignment,
a worm gear continues in alignment regardless of wear, within prac-

Fig. 34. Forward End Torsion Rod, Spring Suspension and Brake Details on Rauch and Lang Car

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Fig. 3.V Details of Rear Wheel Brake Construction as Employed on Several Makes

tical limits, and once properly adjusted can only be deranged by
subsequent adjustments. A better idea of the various essentials
of the drive will be obtained by reference to the rear view of the
Rauch and Lang worm-driven chassis, Fig. 33. As mentioned
previously, a brake is carried on the armature shaft on this car, the
second set being of the internal expanding type operating against
the drums shown attached to the driving wheels, Fig. 34. On the

Fig. 36. Detroit Worm Drive, Hear Axle and Motor
Courtesy of Anderson Electric Car Company, Detroit

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58 ELECTRIC AUTOMOBILES

Argo and several other cars both sets of brakes are of the internal
expanding type, the details of this type of brake construction being
shown in Fig. 35.

This is likewise the case on the Detroit electric, the rear axle
unit of which is shown in Fig. 36, the details of the brake construction
appearing plainly. The Lanchester (British) type of worm is
employed on this car. As will be noted from the part sectional
illustration, Fig. 37, the worm drives through the lower part of the

Fig. 37. Lanchester Worm Gear Used on the Detroit Electric Car

worm wheel and runs in a bath of oil, the oil level being shown in
the figure. In the types previously described, the worm-wheel
housing itself is partly filled with heavy oil.

This sectional illustration also shows a marked difference in
pitch of the worm thread as compared with the Kauch and Lang,
and makes clear the detail of the mounting. The latter consists
of a combination radial and thrust annular ball bearing at each end
of the worm and on each side of the worm wheel. Upon the correct

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alignment of its mounting and proper provision for taking the thrust,
quite as much as upon correct design and accurate machining,
depends the success or failure of any worm drive.

THE CONTROL

Unlike the gasoline car, in which the control of its speed and
climbing abilities is divided between a provision for changing the
gear ratio existing between the motor and the driving wheels, and a
means of increasing the speed and power output of the motor itself
through the admission of more fuel and advancing the point of
ignition, that of the electric vehicle is entirely electric. This is largely
responsible for its great simplicity, all changes in either direction
being effected through a single small lever, the manipulation of which
calls for no more skill than the shifting of a trolley-car controller.
But there is quite as much latitude of design to be found in the
methods of control of electrical vehicles as there is in the method
of transmitting the power to the rear wheels, though, as in the case
of the power transmission, there is more or less similarity in the
principles involved

Counter-E.M.F. Neither a steam engine nor a gasoline motor
can be given "full throttle" to start it without danger of damaging
it. This is due to the inertia of the moving parts, which must be
set in motion gradually and allowed to attain a certain speed
before full power is developed. As the electric motor has no
reciprocating parts, and its revolving armature is carried on the
finest type of anti-friction bearings, the factor of inertia is prac-
tically negligible in so far as it affects starting. It has already
!>een mentioned that the passage of too great an amount of cur-
rent through a wire, i.e., too great for its carrying capacity, has
a heating effect. The heating increases in proportion to the
excess of current flow over the safe capacity of the wire until it is
sufficient not only to burn off the insulation on the wire, but even
to fuse the wire itself.

Now the resistance of the motor armature windings is very low,
but when the armature is revolving, the electrical resistance is
increased by two factors — first, a counter-e.m.f., which is developed
by virtue of the rotation of the armature, and second, the fact that
the wire in the windings becomes warmer, it being a peculiar and

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60 ELECTRIC AUTOMOBILES

inexplicable phenomenon that the resistance of a wire increases in
proportion to its temperature.

Controller. The inability of the motor to carry more than a
fraction of its normal operating current when starting makes neces-
sary the use of something equivalent to the throttle of the steam
engine for accomplishing this necessary control. As not alone the
character of the external source of power — in this case the battery
— is capable of manipulation, but also the internal relations of the
power-producing elements of the motor itself— the armature and
the field — are susceptible of various changes, it will be evident that
the speed range possible under the circumstances may be made as

Fig. 38. General Electric Controller

wide as the designer desires. Ordinarily, most electric vehicles are
provided with a controller giving five speeds forward and two or
three reverse.

Drum Type. In the majority of cases, the controller employed
on the electric automobile is of the drum type, and is practically a
duplicate on a reduced scale of that employed on street railways,
except that the automobile controller is what is known as a contin-
uous torque type. That is, there are no dead spots or idle gaps between
different speeds, the current always being on except when the con-
troller handle is at the neutral position. This insures a continuous
and gradual increase in the speeds without any jerking between
the various steps, and prevents a sudden heavy load being placed

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on the motor, as would be the case where a pause was made in shifting
the handle of the controller over a dead gap. The motor continues
to run at the lower current value until the next set of contacts on the
controller is actually delivering a greater voltage or more current.
The drum, or cylinder, is of insulating material and has mounted
on it a number of copper segments of substantial thickness. These
are so spaced that they make contact with corresponding fingers,
also of heavy spring copper, that are held stationary alongside the
drum. The copper bars on the drum are "grounded" to provide
the continuous torque, that is, they have a common return permitting

Fig. 39. Controller of the Detroit Electric
Courtesy of Anderton Electric Car Company, Detroit

the current to reach the motor constantly, i.e., while changing
speeds. A controller of this pattern is shown in Fig. 38, which is of
General Electric make.

The drum in this instance is seen to be but a section of a cylinder,
on the curved surface of which the spacing of the bars will be ap-
parent. It will also be seen that there is a corresponding finger
making contact with each bar, or in a position to do so when the drum
is turned to bring it around to that particular point. These fingers
are held against the drum very firmly by springs. The open socket
visible at the lower end of each finger is intended to receive the bared
copper wire of which it represents the terminal connection. A varia-
tion of this type of controller is shown in the illustration, Fig. 39, and

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62 ELECTRIC AUTOMOBILES

it v/ill at once be evident that it is provided with a greater numbef
of contacts than is the first controller shown. It should be mentioned
here that the drum is spring controlled as well as the contact fingers,
and is also provided with notched stops in order to hold the contacts
on it directly under the ends of the fingers. In the present instance,
which represents the type of controller employed on the Detroit
car, the contact fingers themselves are directly attached to leaf
springs, which are plainly in evidence. The terminals mentioned are
also to be seen along the bottom, while at the left there is an exten-
sion of the shaft on which the drum is mounted. This carries a

Fig. 40. Chassis of Detroit Electric Car

lever by means of which the drum may be revolved in order to give
the different speeds, forward and reverse. The latter is generally
accomplished by means of a pole reversing switch, most frequently
incorporated directly in the controller itself, and which always
remains locked under normal running conditions. In order to
bring the reverse into play, it is usually necessary to depress a small
pedal or similar release, in order that the driver may not inadvert-
ently start the car backward. A view of the Detroit chassis is
shown in Fig. 40.

Flat Radial Types. A good illustration of a totally different
form of controller is found in the Rauch and Lang cars, and is known
as the flat radial type. In the construction of the earlier models
of the Rauch and Lang car, it was combined with the motor

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and countershaft unit, but is now mounted independently and
in the accompanying illustration, Fig. 41, it is shown separately.
Instead of being mounted
on a drum, the contacts are
placed on a stationary seg-
ment representing about

one-fourth of the arc of a

circle. A pivoted arm, held

at what would be the cen-
ter of the circle, is so

mounted that it may be

turned in order to make

contact with the different

blocks, these in turn being

electrically connected to the

terminals shown attached

to the upright piece at the

left of the controller. Asa Fig4]L FlatRatliu , controller

matter of fact, there are

two separate series of contacts around the arc, and two movable

levers arranged to be moved over them. In this case, the moving

rig. 42. nusn iy|>e 01 toniroiHT

contacts are made of thin copper leaves assembled together and
are held against the contacts by a spring.

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64 ELECTRIC AUTOMOBILES

Flush Types. Fig. 42 illustrates a type of controller which is
designed to be countersunk in the seat of its surface so as to be flush
with the latter. This is a plan view, showing the controller as seen
from above, the pattern being one in which the drum is a complete
cylinder. The left-hand panel of the controller holds the fingers
and contacts for the forward speeds, while those at the right are
the reverse speeds, there being four in each direction in this case.
Further to the right is to be seen the operating lever, the pinion visi-
ble on the end of the drum shaft constituting part of the mechanism
for advancing or returning the drum. This consists of a rack in the
shape of a quadrant which meshes with the pinion in question. At
the extreme left is shown the spring-controlled stop which prevents

the drum from being rotated
more than one space at a
time in either direction, and
holds it with the fingers
pressing directly on the con-
tacts at each point of its rev-
olution. The type of control-
ler employed on the Baker
cars is shown in Fig. 43.
Magnetic Type. To fa-
T ,. Att _ . _ „ , ,. . . cilitate the handling of the

tig. 43. Baker Controller and Operating Lever °

comparatively heavy cur-
rent that is necessary in starting, changing speed in going up hill,
and the like, without having to employ wiring of large size to a
point near the hand-control lever, a modification of the multiple-
unit system of control as used in electric railway service, and par-
ticularly on elevated trains, has been applied to the electric auto-
mobile. In this system only a current of small value is actually
passed through the hand-controlling mechanism, which takes the
form of a small "controller box", as shown in Fig. 44, which repre-
sents part of the control of the Ohio. The controller of the Century
is shown in Fig. 45. By setting this to the speed desired, current
is passed through a magnet in the controller proper. The arma-
ture of the magnet is attracted, and in so doing it closes a switch or
contact for the corresponding speed. There is a magnet or solenoid
for each speed ahead and reverse, which are so connected that, in

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ELECTRIC AUTOMOBILES 65

changing to a higher speed, the contact of the speed below is not
broken until either the switch giving the higher current value is
closed, or the current is shut off, thus releasing all the magnets and

Fig. 44. Control Disk of the Ohio Magnetic Controller
Courtesy of Ohio Electric Car Company, Toledo, Ohio

obtaining the advantages of the continuous-torque type of hand
controller. The arrangement effected by the opened and closed
positions of the various magnets determines the direction and

Fig. 45. Magnetic Controller of the Century Electric Cur

magnitude of the current in the motor circuit in a similar manner
to that provided by the segments and fingers of the drum controller.
The essential difference between the magnetic controller and the

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66 ELECTRIC AUTOMOBILES

ordinary type is that the former is electrically operated, while the
latter is mechanically operated. Hence its location is not governed
by the necessity of mechanically connecting it with the hand lever
through rods, gears, or chains, and it may be placed in any con-
venient location. In the Ohio it is placed under the seat. The
various speeds are obtained by turning the disk on the end of the
contactor box near the driver's hand. Turning to the right gives

Fig. 46. Wiring Diagram for Primary Circuit of the Ohio Magnetic Controller

the various forward speeds in consecutive order. The neutral
position is, as far to the left as the disk will go; by pushing the button
on top the controller may be turned still further to the left to give
the reverse speeds. When in the neutral position it may be locked
there by pushing in the button at the back, and the controller cannot
then be operated until unlocked with a key. Buttons are also pro-
vided for ringing the bell and operating the magnetic brake. The
contacts are made by spring-held carbon brushes pressing against
the inner face of the disk. In this system of control there are two
independent circuits — the primary circuit passing through the mag-

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ELECTRIC AUTOMOBILES 67

netically-operated switches of the controller from the battery to the
motor, and the secondary circuit, which handles the current of
lesser value employed to operate the magnets, and which is controlled
by the movement of the disk mentioned. The primary wiring
diagram of the Ohio is shown in Fig. 46, and the secondary wiring
diagram in Fig. 47.

Duplex Control. To facilitate the handling of closed cars of
the brougham and other large types of enclosed cars seating five or
more passengers, duplicate-control wiring and duplicate-brake pedals

Fig. 47. Wiring Diagram for Secondary Circuit of the Ohio Magnetic Controller

are provided at two positions; one forward, designed to be operated
from a front seat, and the other similarly located with relation to
the rear seat on the same side. Brake pedals and steering connec-
tions are also duplicated, so that to shift the control of the car from
one location to the other, it is only necessary to release the steering
column at one place and insert and lock it in the socket provided
for this purpose at the other. This enables the driver to keep the
way clear ahead no matter how many passengers are carried and
also drive from the rear seat when the load is light.

Care of Controller. The contacts of the hand-operated type of
controller should be inspected at intervals to note whether they are

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68 ELECTRIC AUTOMOBILES

making proper contact or not. In case the spring of one of the fingers
loses its tension, an arc is apt to form between it and the segment
on the drum and burn the metal. The presence of such an arc will
be noted by a peculiar hissing sound which will be plainly audible if
the cover of the controller box is removed and the car run in a com-
paratively quiet place. This action will also take place to a certain
extent if the controller is held between the notches in changing
speed. The blistered surface of the metal thus resulting will make
poor contact, and will continue to burn more and more unless this
condition is remedied by sandpapering the finger and correcting
the tension of the spring so that contact is made all over the surfaces
that touch. If a finger has become badly burned, it should be
replaced and the new one adjusted to an even, moderate tension.
When necessary to face the fingers to the drum, the sandpapering
should be done on the fingers themselves rather than on the seg-
ments of the drum, as the latter are not so easy to replace. The
drum segments should be kept bright and clean, and should be
lubricated occasionally by wiping with a linen rag and some vaseline.

Methods of Control. As it is equally important for the owner
of an electric vehicle to familiarize himself with the manner in which
the amount of current sent through the motor is controlled, quite
as much as with the apparatus for effecting this, it has been thought
advisable to devote a short section to this subject. Before taking
up this matter, it will be well to return momentarily to a previously
discussed subject of series and parallel connections.

Series and Multiple Connections. Each cell of a storage bat-
tery is a complete self-contained unit capable of delivering cur-
rent of a certain amount according to its size and capacity, at an
electrical pressure of slightly more than two volts when fully charged.
For purposes of illustration, each individual cell may be likened to a
pump, capable of exerting a pressure of two pounds. It will be quite
apparent that if 24 such pumps, corresponding to the 24 cells of a
48-volt storage battery, were connected together — the outlet of the
first to the inlet of the second and so on throughout the entire 24 —
the series of units would be capable of producing a pressure of 48
pounds. The water delivered could accordingly be forced 24 times
as far, or as high, as one pump could send it, but the quantity raised
would only be that of which one unit was capable. This analogue

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affords a very clear idea of what is meant by a series connection, a$
the statement just made regarding the ability of pumps so connected
applies literally to the storage cells under the same conditions. Again
taking the 24-cell battery as an illustration, this being the former
standard for light pleasure vehicle use, it will be seen that the
output of the battery connected in series, i. e., the positive of one to
the negative of the next and so on throughout the set, would be the
ampere-hour capacity of one cell.at 48 volts. The voltage is seldom
constant, but ranges from 2.2 to 1.7 volts per cell, according to the
state of charge that the cell is in at the time; but when a number of
cells are connected in series, the voltage of the battery thus formed
will always be that of the voltage of one cell multiplied by the num-
ber in the battery. For purposes of reference, it is customary to
consider the potential of the storage cell as 2 volts.

To return to the analogue of the pumps, where the conditions
are such that a greater quantity of water is required, but it is not
necessary to raise it to more than half the height to which the 24
pumps in series are capable of sending it, they may be arranged in
two series of 12 each. Double the volume of liquid may then be
raised to a height represented by the ability of the 24-pound pressure
developed. The two groups of pumps are still in series, so far as
they alone are concerned, and each group would have but the capacity
of a single pump at twelve times its pressure. But when the inlets
and the outlets of the two groups are brought together in the case of
either pumps or storage cells, the volumetric capacity is increased to
two units at a pressure of 24 pounds or volts. If, on the other hand,
all the inlets were brought together into one connection and all the
outlets into another, there would result a capacity of 12 pumps, at
the pressure of but one. This last-named arrangement is termed
a multiple connection, while that described above is a combination of
the series and multiple connections, and is accordingly designated by
the term series-multiple.

Given 24 cells or more, the number of series-multiple combina-
tions possible is quite extended, but it will be evident that those at
either extreme of the range would be useless for all practical purposes
in the running of an electrical vehicle. It is accordingly customary
to assemble the cells in sets of six or eight connected in series, which
cells are securely packed in oak cases, the number of the units

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employed depending upon the voltage of the motor of the
vehicle.

Resistance in Circuit. Another source of control is to be found
in the motor itself. It will be recalled that the latter generates power
by means of the alternating magnetic attraction and repulsion of
the sections of the armature by the field magnets. The strength of
the latter, as well as that of the electromagnets composing the arma-
ture, is naturally dependent upon both the amount of current sent
through them and its voltage. One of the simplest forms of con-
trol is naturally that in which the entire battery is in series with
the motor, and in which the relation of the two undergoes no change.
In.such a case, resistances of the type shown in Fig. 48 are employed

Fig. 48. Controlling Rheostat

to cut down the current sufficiently to give what are usually termed
the starting speeds. In every case, the full energy of the battery is
being drawn upon, but only a part is being utilized on these first
speeds, the remainder being dissipated by the resistance in the form
of heat. In view of the very short period during which they are em-
ployed, the use of resistances in these starting speeds is not a detri-
ment. This system of control is to be found on the Rauch and Lang
cars, among others, and has the great advantage of discharging all
the cells of the battery uniformly. All the speeds are obtained at
the same voltage and the motor is working at every position of the
controller handle, so that there are accordingly no dead spots and
the circuit is never open, even momentarily. A similar system of

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control is employed on the Baker vehicles. This will be evident
upon a little study of the accompanying diagram, Fig. 49, illustrating
the wiring and all the connections. The large squares, marked plus
and minus, represent the groups of cells into which the battery is
divided. The individual cells in each group are connected in series
and it wall be seen by tracing the connections that the groups are like-
wise in series, a positive being connected to a negative and so on
throughout.

Wiring Diagram. Wiring diagrams appear extremely intricate
to the uninitiated at first sight, but in each instance the course taken
by the current may easily be followed after a little study, and as
familiarizing himself with all the wiring and connections of his car is a

Fig. 49. Control Wiring Diagram

part of the education that no plectric vehicle owner should overlook, it
should not be slighted. The diagram received from the manufacturer
of his car will be a Wue print similar to the one from which the
accompanying illustration was taken, so that it may be studied here
as well as at first hand. Familiarity with one of these diagrams will
prove an "open sesame" to all others, for, while they all differ to a
greater or less extent, it will be easy to trace the different circuits,
once the rudiments are known.

The fact that all of the cells in the battery are in series has
already been mentioned. It will be seen that there are 21 cells in
the battery, giving a working potential of 42 to 60 volts according
to the state of charge. The different points of the controller are
represented by the group of parallel bars in the lower center of the

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72 ELECTRIC AUTOMOBILES

drawing, marked RA, i?-2, etc. In this case it will be noted that
there are four connections of this nature, RA to RA, these represent-
ing resistances to cut down the current for starting. They are accord-
ingly known as starting speeds, and are only designed for getting the
vehicle under way, an operation that calls for a heavy torque or pull
on the part of the motor. This requires a large amount of current
and, as already mentioned, it would be apt to burn out the motor
windings if sent through the latter before it had attained sufficient
speed to build up its counter-e.m.f. to a point where the full cur-
rent may be safely handled. The external resistances themselves
are represented by the bars marked in the same manner, seen diago-
nally to the left and above the controller on the diagram, the connec-
tions between the two being easily traceable.

Further points on the controller are designated as FA and F-2,
and FFA and FF-2, and refer to the connections for altering the rela-
tion of the field and armature. Electric motors employed on auto-
mobiles are generally of what is known as the series type in which
the armature and fields are normally in series with one another. In
other words, the entire current passes through the complete winding
of the motor. By varying this relation in several w T ays, several steps
in the speed control are possible without the intervention of any
resistance. For instance, in the control, as illustrated, the first speed
is obtained by placing the field in series with a resistance, giving a
car speed of 8 miles an hour. By cutting out part of the resistance
and still maintaining the same relation, the car speed is increased to
10 miles an hour, corresponding to the second point on the controller.
At the third point, the resistance is eliminated altogether, resulting
in an increase to 12 miles an hour. A further increase to 14 miles
an hour is obtained by shunting the fields, while the fifth speed of 16
miles an hour results from placing the field in series-multiple. The
last point on the controller shunts the series-multiple field and gives
19 miles an hour.

Office of the Shunt. The term shunt may be explained by
turning again to the water analogy. Electricity, w r ater, or any-
thing else under pressure will naturally follow the path of least
resistance. Take, for instance, a two-foot water main, with a one-
inch outlet tapped into it. The amount of water that will flow
through the one-inch pipe is not alone dependent upon the pressure

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in the main, but likewise upon the resistance offered by the one-inch
pipe. This, by analogy, is practically an application of Ohm's law.
Substitute for the water main an electric circuit. At a certain point,
connect to it a by-path in the shape of another circuit of smaller
wire, and in consequence, representing a greater resistance. The
current can pass through these two circuits simultaneously and
the amount of current in the second, or shunt circuit, will be
smaller than that flowing in the main circuit. In fact, the current
will divide itself inversely as the resistance; that is, if a shunt has ten
times the resistance of the wire in the main circuit between the ter-
minals of the shunt, this shunt circuit will carry only one-tenth of the
total current.

The best example of a shunt connection is to be found in the
case of the volt-ammeter, as shown in Fig. 49. For convenience, the
voltmeter and ammeter (ampere-meter) are combined in a single case
as if they were one instrument, but it will be noted that the connec-
tions are the same as if both were independent. As the voltmeter is
always in circuit, whether the car is running or not, it is wound to a
very high resistance so as to consume the minimum amount of current
for its operation. The shunt marked on the lower part of the diagram,
just under the position of the instrument, is really a part of the am-
meter itself. Where only small quantities of current are to be meas-
ured, the full strength is usually passed directly through the am-
. meter, but on an electric automobile, this would not be practicable
in view of the wide range and the sudden variation of the storage-
battery current, which in starting frequently takes the form of a
heavy surge. The instrument is accordingly designed to employ but
a fraction of the total current, this fraction bearing a direct relation
to the total current passing, the scale reading of the ammeter being
the same as if the full strength of the current passed through it.

It will be evident that any circuit, such as the field winding
of the motor, when placed in shunt with its supply circuit, will only
take an amount of current depending upon the ratio between its
resistance and that of the main circuit, and that economy in current
consumption results. This explains its employment for two of the
higher speeds of the car, the wiring diagram of which is illustrated in
Fig. 49. It will be noted that this connection is only employed for
the higher speeds; in one case, the field windings being in series them-

74 ELECTRIC AUTOMOBILES

selves, and the whole in shunt with the main circuit, to give 14 miles
an hour; and in the second, the field windings themselves being in
series-multiple and in shunt with the main circuit to give a speed of
19 miles an hour. This is due to the fact that at the higher speeds,
only a relatively small amount of power is required to keep the ma-
chine moving. Electric vehicles as a rule do not run at speeds high
enough to make wind resistance a factor of great importance, and as
a result operate under ideal power conditions when once under way.
In other words, the draw-bar pull, by which is meant the effort neces-
sary to keep the vehicle moving, is very light. At starting, however,
in common with other cars, it is heavy, so that it will be evident that
the shunt connection is not applicable to the starting speeds. Its
role is that of economy, rather than power, and to obtain the latter
the series connection is necessary.

Fuses. The fuses are a part of the electrical equipment of the
car, mention of which may be appropriately made in this connection,
as their function is that of acting as a safety valve in the control. The
varying resistances of different kinds of metals have been explained, as
well as the heating effect incident to sending a current through a wire,
particularly where the latter is of a size too small to carry the current.
It is well known that lead and similar materials have a very low melt-
ing point, and advantage has been taken of this in connection with
the phenomenon just referred to, to make what are known as electric
fuses. These are strips of lead alloy of accurately determined sizes,
each size being designed to carry a certain amount of current at a
certain voltage. This is known as the capacity of the fuse, and be-
tween it and the amount of current that the motor or other apparatus
which the fuse is designed to protect can safely stand there is an
ample margin of safety. In consequence, whenever there is a rush
of current through the circuit, as when the controller lever is pushed
sharply forward toward the full on point, and the brakes happen to
be holding the car, the fuses will "blow out" or melt, and save the
motor from destruction.

Electric Brake. In addition to the usual mechanical brakes, the
construction of which is along lines practically identical with those
employed on gasoline cars, some manufacturers equip their cars with
an electric brake. Just how this acts will be clear from a perusal of
the chapter devoted to a description of the motor and its method of

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operation. It will be evident that upon reversing the function of the
motor and driving it from an external source of power, which in this
case will be the motion of the car itself, it will act as a generator
of electric current, and in doing so, it will absorb power in proportion
to the speed at which it is driven. Connections are accordingly
provided on the controller to permit of this, but the motor provides
such an extremely powerful brake, that this has been regarded as a
disadvantage in some cases, so that certain makes of electrics are
only equipped with mechanical brakes.

This disadvantage is doubtless due to the fact that the series
type of motor ordinarily employed on the electric car does not lend
itself readily to this service. Its braking power increases as the
square of the speed of the car, i.e., at sixteen miles an hour, the effect
is four times as great as at eight miles, and when suddenly applied
this is apt to stop the car very suddenly, much to the detriment of
its tires and mechanism, if not to the occupants themselves. Should
a small particle of dust or burnt metal lodge on a contact and momen-
tarily prevent the brake from "taking hold", the motor will suddenly
"build up", with disagreeable results.

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PART II

CARE AND OPERATION OF THE ELECTRIC

CHARGING THE BATTERY

SOURCES OF CHARQINQ CURRENT

Sources of Direct Current. Small Generators. There are few
towns, or even villages, in this country at the present day that cannot
boast of electric-lighting facilities, so that the owner of an electric
vehicle will find it possible to obtain charging current for the main-
tenance of this type of automobile regardless of where he lives.
In case he should reside too far outside the corporate limits of a village
to find such service at his command, or in case he is of a sufficiently
meclianical turn of mind to undertake it, he will find apparatus for
generating the current on his own premises available for a com-
paratively moderate outlay. Though not the simplest, a small direct-
current dynamo driven by a gasoline engine requires but little attend-
ance, and will prove by far the most economical method of charging.
This is particularly the case where the generating set's chief employ-
ment is that of lighting the house, although where an isolated plant
may be installed, the owner of an electric vehicle will find it a great
advantage for charging purposes alone.

This may be seen from the fact that in small towns and villages
rates for electric current are usually high. The power unit, the watt,
has already been explained. A kilowatt is 1000 watts, and electric
current is sold by the kilowatt hour, which means the employment
of one kilowatt of current for one hour. Where current is purchased
in comparatively small quantities, the rate is seldom less than 10 cents
per kilowatt hour, and sometimes 15 cents, or more. With an ordi-
narily efficient generator and gasoline engine, current may be pro-
duced in a small isolated plant for less than 5 cents per kilowatt hour.

The average runabout battery requires 75 to 80 ampere hours

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78 ELECTRIC AUTOMOBILES

for a charge, while a surrey, phaeton, victoria, brougham, or similar
type will need 100 ampere hours. Current is charged for by the watt
hour, which is a current of one ampere at a potential of one volt,
flowing for one hour.

Service Mains. If the current be taken from the service mains
at 115 volts, the charge for the runabout battery would be 75X115
= 8625 watt hours, or more than 8 \ kilowatt hours. The cost of
this would be 86 cents at a 10-cent rate. Even where current is to
be had at more favorable rates, such as 7 or 8 cents a kilowatt hour, a
small engine and dynamo are very much more economical where no
extra attendance has to be figured on. That is, where there is a man
of all work about the place, this is something that may well fall within
his province. Where the generator may also be used for lighting,
the cost for charging will be reduced to a minimum. In the majority
of instances, however, the difference in the cost of charging the
battery in this manner will not be found to represent a sufficient
inducement to make it practical to undertake the initial outlay
required for a small current-generating plant, although the saving
over a period of two or three years would represent no inconsiderable
offset to the original investment.

Street Railways. Direct-current service is now seldom obtain-
able, except where concessions may be made to the automobile owner
by the local street railway. In the latter case, current is usually
obtainable at a lower rate per kilowatt hour than would be charged
by a lighting company, but the advantage is not as great as would
appear at first sight, owing to the higher voltage. Current from a
trolley line would be at 550 volts, and the difference between the latter
and the voltage required to charge the battery would represent a
loss, as it would have to be dissipated through a resistance. The
ability to utilize the current from street-railway mains, particularly
where long tours have been undertaken, has often proved a great
help, however, and where no other service is available it may be
employed regularly for charging by installing apparatus for handling
it. Although a shock from a circuit at this voltage (550) is not
generally considered fatal, it so often proves otherwise that its use
involves an element of danger.

Sources of Alternating Current. Turning now to the usual
source of electricity, the alternating current, one is confronted with

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ELECTRIC AUTOMOBILES 79

Fig. 50. Motor-Generator Bet, 115 A. C. to 125 D. C.

the fact that the charging current must in all cases be "direct", never
"alternating".

Alternating current has been found much more practical for
long-distance transmission and distribution, and its use is now very
general throughout the country, so that where the owner of an electric

Fig. 51. Motor-Generator Set, 220 A. C. to 110 D. C.

89 r^^\o a

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80 ELECTRIC AUTOMOBILES

vehicle decides to fit up his own garage for storing and charging the
car, the first thing to be considered will usually be some means of
rectifying the alternating current, that is, making it direct. This
may take several different forms, such as the motor-generator set
and the mercury arc rectifier, but for reasons which will be made plain
the mercury arc rectifier will be found the most practical and eco-
nomical apparatus for the purpose.

Motor Generator. Where there is a considerable amount of
charging to be done, the motor-generator set is frequently employed.

Pig. 52. IMotor-Gcnerator and Charging Panel for Charging Twelve Electric Trucks
Courtesy of Curtis Publishing Company, Philadelphia

This consists of an alternating-current motor and a direct-current
generator combined in a single unit, both armatures being on the
same shaft, the supply current simply being utilized to run the motor.
A set of this kind is shown in the accompanying illustration, Fig.
50. It has two great drawbacks for private use in that the initial
investment is high and that skilled attendance is required. Its
efficiency is also comparatively low, particularly at light loads.
Fig. 51 shows a smaller type of motor-generator set. In the first
case, the apparatus is designed to take alternating current at 115
volts and generate a direct current at 125 volts; while in the second

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ELECTRIC AUTOMOBILES 81

instance the alternating current is 220 volts, and the direct 110, but
such sets are obtainable for any commercial voltage and frequency
of alternating current. In Fig. 52 is shown a very well-arranged and
complete motor-generator charging plant.

Mercury Arc Rectifier. Owing to its simplicity, as well as to the
fact that it entirely automatic in action, the mercury arc rectifier

Fig. 53. Switchboard, Fig. 54. Switchboard,

Front View Rear View

has come into very general favor for storage-battery charging. The
outfits are compact and, while partly of glass, they are durable and
easily installed. The apparatus itself is showTi in Figs. 53 and
54, giving, respectively, a front and rear view; the connections are
shown diagrammatically in Fig. 55. It w T ill be seen that the panel
board of the instrument incorporates everything necessary for regula-
ting the charge, including a voltmeter, an ammeter, resistance, main
switch, starting switch, circuit breaker, and fuses. The circuit
breaker is a device designed to protect the apparatus with which it is
connected by opening the circuit when there is an excess of current,

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or when the current supply is accidentally cut off. By opening the

circuit as soon as this occurs a rush of current through the apparatus

is prevented when the service

is resumed. Should it fail to

act, the fuses represent the

second step in the protective

link, but naturally their only

function is to rupture the

circuit by melting under the

heating effect of an excessive

flow of current.

H As its name indicates,
the mercury arc rectifier is
an apparatus in which advan-
tage is taken of a peculiar
property of the electric arc
when established in a vacuum

Fig. 55.

Wiring Diagram for Mercury Arc
Rectifier Circuit

and in the j/resence of mer-
cury vapor. •The device con-
sists of a glass vessel, Fig. 56,
from which the air has been
exhausted and a certain quan-
tity of metallic mercury in-
serted. The tube, as it is
called, also has fused into the
glass the several connections
necessary. The one negative
terminal, called the cathode, is
sealed into the bottom of the
tube while two positive ter-
minals, called anodes, are on
opposite sides and a short dis-
tance above the cathode. The
anodes are graphite and the
cathode mercury. When at
rest, there is no electrical con-
nection between them. A starting anode is accordingly provided.
This is much smaller and is situated close to the cathode. If the tube

Fig. 56. Mercury Arc Rectifier Tube

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ELECTRIC AUTOMOBILES 83

be rocked gently after the switch has been closed, an arc is established
between these two points. This liberates sufficient mercury vapor to
start the main arc, and the apparatus is then in operation. As soon as
this occurs, the starting switch is opened. A reactance coil,£s§££
below the panel board in the illustration, completes the rectifier. It
sometimes happens that the arc becomes accidently disrupted,
regardless of the length of time the rectifier has been running, and
to guard against stopping the charge in this manner, particularly
where charging is carried on during the night, an automatic starting
device is provided. This takes the form of a shunt coil and a sole-
noid, or hollow electromagnet, in which a plunger operates. When
the arc is broken, the current is shunted through this solenoid and
the plunger serves to shake the tube gently, exactly as when it is
started by hand. This immediately re-establishes the arc and the
charge is continued. Regardless of how often the main arc may be
broken during the course of a charge, the rectifier is immediately
restarted as long as the current is on. The theory of the transforma-
tion from alternating to direct current by the mercury arc is one
of the most interesting of electrical phenomena, but, as the owner
of the vehicle only is concerned with its practical side, it would be
out of place here.

METHOD OF CHARGING

Making Proper Connections. At the present day, lead batteries
are used almost exclusively for electric-vehicle use, and while dif-
ferent makes will vary slightly in design or construction, the differ-
ences are rarely material, so that the following description, as well
as the terms given, applies equally to all. Batteries are not usually
shipped with the vehicle itself, but are packed separately in a charged
condition; as a freshening charge is required before the battery is
used, it will prove an advantage to carry this out before placing the
battery in the car. The groups of cells must be connected in series —
the plus terminal of one group to the minus terminal of the next,
and so on, the final positive and negative terminals of the entire set
being connected respectively to the positive and negative terminals of
the source of the charging current. The greatest care must be taken
to see that the charging current flows into the battery at the positive
pole, as sending a current through in the wrong direction will not

84 ELECTRIC AUTOMOBILES

only fail to charge it, but will do a great deal of damage and seriously
impair the life of the battery.

Determining Polarity. Where the polarity of the charging ter-
minals is unknown, the simplest method of determining it is to take
a glass of water into which a few drops of acid or a little salt has been
put. Place the wires in it, taking care to keep them well separated.
Bubbles of gas will form on both of the wires, but one will give off
gas much more freely than the other. This is the negative pole and
should be attached to the negative charging terminal of the battery.
The other wire will give off comparatively little gas and will rapidly
blacken. This is the positive pole. There are numerous other
tests equally simple, but as this calls for apparatus easily obtained
anywhere, it will be an advantage to memorize it, particularly
as occasions will arise when the vehicle will have to be charged away
from home in the absence of the usual facilities. The wire or con-
nections to the battery from the charging side must be of ample
size to carry the heaviest current used in charging without undue
heating. The sizes used in the car itself form the best guide for this.

Voltage After Charging. The operation of charging will be
the same whether the battery is in or out of the vehicle, but as the
battery was fully charged when shipped, this initial charge will be
a short one. But the greatest care must be taken to charge the
battery fully. The voltage per cell should reach 2.55 volts, with the
current still on, when the cell is fully charged. This would mean
60 to 62 volts for a 24-cell battery.

These voltages, Table II, are approximate and are intended for
guidance only. A battery when cold will show a higher voltage than
one at a higher temperature, and the same thing is true of a new
battery as compared with an old one. It is not safe to regard a fixed
voltage as the end of the charge, but a maximum voltage for the
battery in question.

The rubber plugs should be removed from the cells during the
operation, as the cells will be gassing very freely toward the end of
the charge. This gas is hydrogen and, as it is not only highly
inflammable, but likewise very explosive when mixed in certain pro-
portions with oxygen, care must be taken not to bring a naked flame
anywhere near the battery while in this condition. The plugs may
be left out for a short time after the charge is finished to permit the

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TABLE II
Charging Voltage for Lead Batteries*

1 —\

Volts At

Number of Cells

Start

Finish

102

107

112

100

117

105

123

110

128

♦Cuahing and Smith, Electrical Vehicle Handbook.

escape of the gas. The latter carries more or less of the acid elec-
trolyte with it in the shape of a fine spray, and care should be taken
to keep this spray from falling on the clothes or similar objects, as it
causes ruinous stains, and only a comparatively small quantity is
required to burn holes in cloth.

Temperature of Battery. When the battery is out of the vehi-
cle, as in the case under consideration, the matter of temperature is
not so important, but when it is in the vehicle, precautions must be
taken to provide all possible ventilation. The charging causes a rise
in the temperature of the cells and this should never be allowed to
exceed 110° F. under any circumstances. The lower it can be kept
the better, and. a battery which is never allowed to exceed 90° F.
while under charge will last much longer and give better service.
The reason for this is to be found in the fact that the heating causes
the active material in the grids to expand. If this expansion be
excessive, as where the temperature is allowed to get too high,
the material is apt to bulge completely out of the retaining pockets,
so that it does not return when cooled off again. This destroys its

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connection with the lead grid, cutting down its conductivity and
greatly lowering the efficiency of the cell. Furthermore, after this
bulging of the paste has occurred, there is the possibility at any
time that flakes of active material will drop down below the plates
and cause a short-circuit. Even if it does not cause this trouble,
the accumulation of the material in the bottom may soon be enough
to short-circuit the whole cell unless it is of the type provided with
an especially deep space below the plates. The temperature should
accordingly be noted from time to time during the charge and, if
it passes safe limits, the charging rate must either be reduced or

Fig. 57. Typical Battery-Charging Rheostat
Courtesy of General Electric Company, Schenectady, New York

discontinued altogether in order to give the cells an opportunity to
cool off.

Experience has shown that the best results are obtainable from
a storage battery when its temperature is maintained between 70°
and 90° F. during both the charge and discharge. A considerably
lower temperature will materially reduce the available charge of the
battery, but this does not tend to injure it in any way, as a return to
normal temperature restores its capacity. This is not true of a
higher temperature, however, for if it is kept above normal for. any
length of time the wear on the plates is excessive.

Charging Rate. Every battery has a certain charging rate, and
this should be taken from the chart sent with it by the manufacturer.
It will be found that there are two rates — a starting rate and a
finishing rate — and, as it is during the final part of a charge that the
greatest wear falls on the battery plates, instructions regarding the
strength of the current to be employed for starting and finishing the

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ELECTRIC AUTOMOBILES 87

charge should be closely followed. The more slowly a battery can be
charged within reasonable limits, the better will be its condition at
all times, and the longer its life. It is not always convenient, how-
ever, to give a battery as slow a charge as desirable in electric vehicle
work. On the contrary, the car is often wanted at short notice not
long after the battery has been discharged, and consequently it

is abused by being charged at
an injurious rate for a short
period. Theoretically, 10 am-
peres for ten hours and 50
amperes for two hours are the
same and should give a battery
capacity of 100 ampere hours.
But the "storing" of the cur-
rent is purely a process of
chemical conversion that can-
not be accomplished at a rapid
rate without injuring the plates.
The manufacturer specifies
that each type of cell shall be
started at a certain charging
rate, say, 10 amperes. The
charging rheostat is manipu-
lated until the ammeter Bhows
that the amount of current in
question is going into the bat-
teries. Figs. 57 and 58 show
two forms of charging rheo-
stats. This rate is maintained

Fig. 68. Typical Charging Rheostat ., ., - , . ,.

until the voltmeter indicates
that a certain potential has been reached, which is usually a voltage
of about 2.55 volts per cell, measured with current flowing. The
charging rate should then be reduced to 4 amperes, which causes a
considerable drop in the battery voltage. This reduced charging
rate is then maintained until the voltage again rises to the point
at which the voltmeter stood when the current was reduced, i. e.,
until the voltage ceases to rise, which will generally be the same as
the voltage at which the high rate of charge must be reduced. The

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88 ELECTRIC AUTOMOBILES

total voltage of the battery is usually taken as an indication, and
when this fails to reach the desired figure, it is usually a symptom
that some of the individual cells have defaulted. The remedy for
this is given later.

Precautions. At the end of both the starting and finishing
periods, the cells will be gassing freely, i.e., giving off large quantities
of hydrogen, and for this reason the battery space of the vehicle
should be open and the room in which the charging is done should
be well ventilated. In addition to being highly inflammable and
explosive, this gas is also very irritant to the throat and lungs and
when present in any quantity causes constant coughing. Nothing
but electric light should ever be employed in a private garage used
for the charging of an electric car.

There are a number of other precautions to be observed when
placing the battery on charge in the vehicle besides that of providing
ample ventilation, as already mentioned. The controller handle
should be locked in the off position, the lamps switched off, and the
beU should not be rung during the progress of the charge. The
reason for the first of these precautions is self-evident and for the
latter two is found in the increased voltage during the charge, and
particularly as it approaches completion. This would be sufficient
to cause the lamps to burn out and to injure the bell. It is important
that the manufacturer's directions with regard to the charging rate
be closely observed. In order to be certain that this is done, the
current should be measured by an accurate ammeter mounted on a
panel board in the garage. The ammeter on the vehicle should never
be employed for this purpose, as the vibration and road shocks to
which it is subjected make the accuracy of such a delicate instrument
a very uncertain quantity.

Starting the Charge. To start charging, the rheostat handle
should be turned so as to throw all the resistance in. The switch
on the panel board should be open, and the charging plug should
then be inserted in its receptacle on the car. These plugs are usually
made so that they can be inserted only in the proper way, and there
is no danger of reversing the polarity of the current in this manner.
Where not thus designated, the terminals are properly marked and
care must be taken to see that the plug is correctly inserted. When
the plug is in, the switch may be thrown on. Battery manufacturers

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ELECTRIC AUTOMOBILES 89

supply tables showing what the starting and finishing voltages of
the battery should be, as well as its final voltage; but as this will be
influenced by varying conditions, such as the temperature of the
battery and the age of the plates, the figures given are only approxi-
mate. Furthermore, a new battery will have a higher final voltage
than an old one under the same temperature conditions, and both
old and new cells will read higher with the temperature low than
when it is comparatively high. In view of the foregoing, a fixed
voltage cannot be considered as an accurate test in determining the
completion of the charge. Instead, a maximum voltage will be
found the only certain indication. This may be determined by
noting when the voltage ceases to rise as the end of the charge
approaches.

When charging during the day, the progress of the charge should
be noted at half-hour intervals, the current being cut off as soon
as the voltage has stopped rising. One of the commonest ways of
abusing a battery is to overcharge it. This is most often done under
the impression that an increased mileage will result, doubtless on
the theory that if a certain distance can be covered by the vehicle on
a full battery, "cramming" it a bit should give as many more miles
proportionately as the excess charge bears to the normal capacity.
Needless to add, this is a fallacy. No additional mileage will result
from excessive overcharging, and where this occurs it causes the
plates to deteriorate and thus reduces instead of increases the dis-
tance that may be covered. A direct indication of excessive over-
charge takes the form of a noticeable increase in the temperature of
the cells.

The question of temperature during the charge has already been
touched upon. This should not exceed 110° F., and when charging
with the battery in the vehicle, as is usually done, the middle cells
should be taken as a guide. Unless it cannot be avoided, it is prefer-
able not to allow the cells to rise above 100° F., reducing the charging
rate or stopping the charge altogether for a time if the temperature
does reach this point.

Automatic Charge-Stopping Device. Where constant attend-
ance during charging is neither practicable nor desirable — as in the
case of the owner who takes care of his own car — an automatic
charge-stopping device is a great convenience. This is an attach-

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ment to the Sangamo ampere-hour meter, which is described in
detail, page 158. It consists of a solenoid-actuated trip circuit
breaker, Fig. 59, which is
set in operation by the
pointer of the meter when
closing a circuit on arriv-
ing at the point of full
charge, a point which has
been fixed by the operator
in advance. However, as
it is necessary to put more
current into a storage
battery than can be taken
out of it (see Fig. 11), a
certain amount of over-
charge must be allowed
for in every case. The
amount necessary will
naturally depend upon
the condition of the bat-
tery as influenced by its
age and the treatment it
has received, but it can
be determined readily after a little experience. In the Sangamo
differential shunt ampere-hour me ter referred to, a sliding adjust-
ment is provided for this purpose and, once set, it need not be

disturbed for a consid-
I I y^i JjTX erable period unless

made necessary by a
change in the condition
of the battery. With
this adjustment made,
the charging can be done
by any unskilled laborer,
as it is only necessary to
make the charging con-
nection and leave it.
Since the circuit cannot

Fig. 59. Solenoid-Actuated Trip Circuit Breaker

Courtesy of Sangamo Electric Company,

Springfield, Illinois

To Load

Fig. 60.

To Battery

Circuit Diagram of Charge-Stopping Device,
Sangamo Amn»»-e-Hour Meter

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TABLE II!
Temperature Correction for Specific Gravity of Electrolyte*

30° F.

40° F.

60° F.

70° F.

80° F.

90° F.

100° F.

1.317

1.313

1.310

1.307

1.303

1.300

1.297

1.293

.12

.08

.05

.02

1.298

1.295

.92

.88

.07

.03

.00

1.297

.93

.90

.87

.83

.02

1.298

1.295

.92

.88

.85

.82

.78

1.297

.93

.90

.87

.83

.80

.77

.73

.92

.88

.85

.82

.78

.75

.72

.68

.87

.83

.80

.77

.73

.70

.67

.63

.82

.78

.75

.72

.68

.65

.62

.58

.77

.73

.70

.67

.63

.60

.57

.53

.72

.68

.65

.62

.58

.55

.52

.48

.67

.63

.60

.57

.53

.50

.47

.43

.62

.58

.55

.52

.48

.45

.42

.38

.57

.53

.50

.47

.43

.40

.37

.33

.52

.48

.45

.42

.38

.35

.32

.28

.47

.43

.40

.37

.33

.30

.27

.23

.42

.38

.35

.32

.28

.25

.22

.18

.37

.33

.30

.27

.23

.20

.17

.13

.32

.28

.25

.22

.18

.15

.12

.08

.27

.23

.20

.17

.13

.10

.07

1.203

.22

.18

.15

.12

.08

.05

1.202

.98

.17

.13

.10

.07

1.203

1.200

.97

.93

.12

.08

.05

1.202

.98

.95

.92

.88

.07

1.203

1.200

.97

.93

.90

.87

.83

1.202

.98

.95

.92

.88

.85

.82

.78

.97

.93

.90

.87

.83

.80

.77

.73

.92

.88

.85

.82

.78

.75

.72

.68

.87

.83

.80

.77

.73

.70

.67

.63

.82

.78

.75

.72

.68

.65

.62

.58

.77

.73

.70

.67

.63

.60

.57

.53

.72

.68

.65

.62

.58

.55

.52

.48

1.167

1.163

1.160

1.157

1.153

1.150

1.147

1.143

•Cushing and Smith, Electric Vehicle Handbook.

be broken until the predetermined number of ampere hours have
been absorbed by the battery, the latter will remain connected to
the mains until fully charged, so that there is no danger of either
undercharging or overcharging, as may occur where the charge is
simply limited by the time considered necessary. The circuit of
this charge-stopping device is shown by the diagram, Fig. 60. The
circuit breaker also opens the exciting circuit, so that it carries the
current only for an instant.

Rated specific gravity for various stages of charge is based on
a temperature of 80° F. Corrections for temperatures above and
below this point may be made from Table III.

Testing Progress of Charge* Upon the completion of the charge,
the rheostat handle should always be turned back before opening

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the battery switch. It is essential that any voltage readings taken
as a guide of the battery's condition should be noted only while the
charging current is on. This applies likewise
to readings during the discharge of the bat-
tery, which should be taken while the vehicle
is running, as the voltage with the battery
standing idle is of no value as an indication
of its condition.

But the voltage alone must not be de-
pended upon. The specific gravity of the elec-
trolyte as well as the voltage will rise and
reach a maximum as the end of the charge
approaches. Specific gravity readings should
therefore be taken with the hydrometer syringe
provided for this purpose. This instrument
consists of a glass syringe in which there is a
hydrometer, Fig. 61. By inserting the point
of the syringe in the venthole of a battery,
it may be filled with the electrolyte, thus
causing the hydrometer to float. The specific
gravity of the solution may be noted and the
latter replaced in the cell without any neces-
sity for handling. Several cells in various ^ 62 Syringe Hydrom .
parts of the battery should thus be tested as eterSet

Fig. 61. Acid Testing Set in Separate Parts
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TABLE IV
Baume Scale of Specific Qravities

Baume

Specific Gravity

Baume

Specific Gravity

1.000

1.141

1.006

19-

1.150

1.014

1.160

1.021

1.169

1.028

1.178

1.035

1.188

1.043

1.198

1.050

1.208

1 • 8

1.058

1.218

1.066

1.228

1.074

1.239

1.082

1.250

1.090

1.260

1.098

1.271

1.106

1.283

1.115

1.294

1.124

1.306

1.132

1.318

a check of the voltage. Another form of testing set is shown in
Fig. 62. When fully charged, the specific gravity of the electrolyte
should be between 1.270 and 1.280. Because of the spraying
through the ventholes when the cells are gassing freely, and the
loss by sloppage and evaporation, there is a gradual lowering of
the specific gravity. It may be permitted to run as low as 1.250
when fully charged. It is not necessary to make both the voltage
and specific gravity tests every time the battery is charged, but
they should be carried out at least once a fortnight, when all the
cells should be tested to determine if they are in uniform condition.

Baumi Scale. Hydrometers are often graduated according to
the Baumfe scale. The Baume scale for liquids heavier than water
is based upon the following equation:

145
145 — BaumS degrees

Table IV gives the corresponding specific gravities and Baum6
degrees.

Should the specific gravity of some of the cells be lower than
the remainder of the battery, the low cells should first be charged
separately at a low rate. If the specific gravity increases, it is an
indication that the cell had been discharged to a lower point than the

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94 ELECTRIC AUTOMOBILES

others and simply needed additional charging. Should this not be
the case, and if neither the specific gravity increases nor the tem-
perature rises rapidly during the charge, it indicates that the gravity
of the electrolyte has been lowered by the addition of water to com-
pensate for loss due to leakage or similar cause. The cell should
accordingly be examined for the cause of the loss by sawing through
the connections or straps and removing the cell from the battery.
If the jar is found to be broken or cracked, a new one should be
substituted, new electrolyte of the same specific gravity as that of
the remaining cells put in, and the cell fully charged. The specific
gravity of the electrolyte should then correspond with that in the
other cells. If the loss of electrolyte has been due merely to slopping
over, electrolyte should be added and the whole tested for the right
specific gravity. The outside of the jar and the tray beneath it should
be thoroughly cleaned, and the cell put back and its connections
burned into place, care of course being taken to have positive and
negative plates connected as they were before removal.

As the electrolyte of the Edison cell does not vary with its
state of charge, the specific gravity test cannot be employed, the
voltmeter affording an accurate indication of the condition of the
cells. Electrolyte cannot be lost from the Edison cell as it is sealed
in, but there is a certain amount of loss by evaporation which must
be replaced with distilled water.

Electrolyte, Manufacturers of storage batteries usually recom-
mend that small users purchase their supplies of electrolyte from them
in order to be certain of its purity and specific gravity. Where this
is not convenient, the owner of the electric vehicle may mix his own
solution. This should consist of distilled water and pure sulphuric
acid in the proportion by volume of one part acid to four and three-
quarter parts of water for electrolyte of 1.200 specific gravity, or one
part acid to three of water for 1.275. A glass, porcelain, or earthen-
ware vessel must be employed for mixing the solution, and the acid
must be poured very slowly into the water. Never pour water into
acid, for while the effect of slowly adding acid to water is negligible,
the adding of water to concentrated acid is accompanied by violent
chemical action and an evolution of heat will usually break the
containing vessel and always cause a dangerous spattering of the
acid.

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The sulphuric acid should be chemically pure, and, wherever
possible, distilled water should be used. If this is not obtainable,
the use of clean rain water is recommended as being likely to contain
less impurities than any other. The keeping of the electrolyte free
from impurities is a matter of the utmost importance and one that
must ever be borne in mind. All dirt and foreign substances, both
liquid and solid, must be rigidly excluded. A piece of iron in the
shape of a stray tack, small nut, or wire may fall into a cell and ruin
it before its presence is discovered. The presence of iron will be
indicated by the electrolyte and the positive plate becoming a
dirty yellow color. Some other impurities also make their presence
readily known, for instance, chlorine will give off fumes that are
easily recognizable by their disagreeable odor.

Whenever such a condition is discovered, the only remedy is to
dismantle the cell immediately, regardless of the state of charge or
discharge it may be in. Discard the electrolyte and the wood separa-
tors, and thoroughly rinse in running water all parts of the cell,
such as the jar, rubber separators, and both of the elements; the
latter should be washed separately. Reassemble with new electro-
lyte of the same specific gravity as that discarded, and new wood
separators. Charge the cell and discharge fully several times.
After the last of these discharges and before recharging, take the
cell apart a second time, again discarding the electrolyte, rinsing
the parts of the cell in running water and soaking the wood separators
in several changes of water. The cell may now be reassembled
permanently with electrolyte of 1.200 specific gravity. It should
be given a long charge before being put into service again. Care
must be taken not to allow the negative elements to become dry
at any time during this operation, in fact, it is better to keep both
sets of plates under water until reassembled.

Dangers of Overcharging. To revert to the subject of charging
in general, too much cannot be said regarding the evils of giving an
excessive overcharge, an abuse which may occur in two ways: charg-
ing the battery for too long a time, and charging too frequently.
The commoner of these — that of charging too long a time — is easy
to avoid. The other is not so apparent, and is the result of a practice
which is apt to be indulged in by the uninitiated owner of an
electric car, being due to a desire to have it always ready to run

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96 ELECTRIC AUTOMOBILES

its available mileage. This is the custom of charging too frequently.
For instance, if the capacity of the battery will run the car 40 miles
on a charge, and but 5 miles are covered and a short charge given,
then 10 miles are covered, and a second charge, followed by a second
and third installment of 10 miles with a charge between each and
after the last, it is obvious that but 35 miles have been covered
altogether, but the battery has been charged four times. This is
three times more than was necessary under the circumstances,
besides which the available radius was not covered, so that the
battery would really not have been discharged had the entire dis-
tance in question been covered without recharging. The greatest
wear on the plates of a battery occurs during the final part of a
charge, so that the oftener the battery is charged the shorter its life
will be. As stated at the outset, the life of the very best cell made
is measured by a certain number of discharges, but this is on the
assumption that it is not recharged until actually discharged each
time. Where a vehicle is employed for short runs, such as those
mentioned, the capacity of the battery will not give as great a
mileage as if the entire distance were covered in one run. When
covering but a few miles in daily service, it is not advisable to
recharge until between 50 and 75 per cent of its capacity has been
exhausted.

Where it is desired to use the car within a comparatively short
time after the battery has been exhausted, it is permissible to hurry
the charge within certain limits by using a higher rate than normal.
This should not exceed 50 per cent increase under any circumstances
and should be employed only at the start of the charge. When the
"finishing" voltage has been reached, the charge should be reduced
to the normal starting charge, the remainder of the charge being
carried out as if the battery had been started on the latter. Great
injury may be done to the plates by "pounding" a nearly full battery
at a high rate of charge. The foregoing precautions do not apply
to the Edison cell.

Time Required to Charge. The time required for charging will
naturally depend upon the extent of the preceding discharge. If the
latter has been two-thirds of the rated capacity of the battery, the
usual pleasure car will require about three hours at the starting rate
and one and a half to two hours at the finishing rate. In other words,

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about 10 to 15 per cent in excess of the amount discharged is usual.
At least once a fortnight, a prolonged charge should be given by
continuing the charge for one hour after the specific gravity of the
electrolyte has ceased to rise. Where a vehicle is maintained by its
owner in a small private garage, and is used more or less during the
day, it will be found a great convenience to do most of the charging
during the night, and for this purpose the mercury arc rectifier,
described in the chapter on "Methods of Charging", will be found
a great help. Where direct-current service is available at 110, 220,
or 500 volts, such an adjunct will naturally not be necessary. In
over-night charging, precautions must be observed to prevent an
excessive overcharge. To do this, a careful estimate of the current
required to fully charge the battery must be made before putting it
on charge, and the rate adjusted accordingly. If 12 hours be avail-
able for charging and 84 ampere hours are necessary, the average
rate of charge must be 7 amperes. Should the time be only 9 hours,
as where a vehicle has been used in the evening and is wanted again
early in the morning, the average rate would be slightly more than
9 amperes. Where 72 ampere hours are required in 9 hours, the rate
would be 8 amperes, and so on. The rate, however, will also depend
to some extent on the voltage of the charging circuit, in charging
from a source with constant voltage, the rate into the battery
will fall as the charge progresses. This is also the case where the
charging is done with the aid of a mercury arc rectifier. After the
charge is ended, the voltage will drop immediately when the battery
is disconnected.

Charging an Edison Battery. The charging rates of Edison
cells are based on a voltage of 1.85 volts per cell, so that the potential
required to charge a battery of this type is as follows:

Number or Cells

Volts Across Cells

18.5

37.0

55.5

74.0

92.5

111.0

130.0

148.0

167.0

100

185.0

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These voltages are just sufficient to charge the number of cells
in question at the normal rate during the end of the charge, as the
alkaline cell increases its voltage during charge in the same manner
as the lead cell, there being also a similar drop in voltage when the
charging current is shut off. While a slight reduction in voltage
from the potentials given will not materially affect the charge,
allowance should be made for what is required in every case, if neces-
sary, by charging the battery in series multiple.

Owing to their construction the Edison cells are capable of being

boosted at high rates when it is necessary to charge quickly, but the

temperature must not be allowed to exceed 115° F. The following

are the boosting rates recommended by the makers as the result of

experience:

5 minutes at 5 times the normal rate
15 minutes at 4 times the normal rate
30 minutes at 3 times the normal rate
60 minutes at 2 times the normal rate

The sizes, capacities, charge and discharge rates of the Edison
cells are as follows:

Type A-4

A-5 1 A-6

A-8

A-10

A-12 j

Capacity 150 ampere hours .
Normal charge 1 ^
Normal discharge J

187.5

37.5

225
45

300
60

375
75

450
90

They are capable of discharge rates in excess of these figures in
the same proportion as the boosting rates.

BOOSTING

Advantages of Boosting. The term "boosting" as applied to
electric-vehicle batteries may be defined as "auxiliary charging", and
must not be confused with its use in connection with the charging of
large stationary batteries. As the lead-plate cell becomes com-
pletely charged, its voltage rises to 2.5 volts per cell, which for the
55 cells required to deliver current at 110 volts, would mean a poten-
tial of 137.5 volts, or an increase of more than 20 per cent over that
of the generator. The latter, not only being a constant potential
dynamo, but also being called upon to deliver current for other
service while charging the battery, it is necessary to raise the voltage

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of the charging current in order that it may exceed that of the bat-
tery without, at the same time, altering the output of the generator.
For this purpose, what is known as a "booster" is employed, i.e., a
motor-generator which imposes a higher voltage on the charging
current than that at which it is produced by the main generator.

In the case of a vehicle battery, it usually implies a partial
charge given in a comparatively short time and at current rates con-
siderably higher than normal, and
it represents a practice which has
had an important influence on the
use of the electric vehicle for con>
mercial purposes. For example,
many of New York's several
thousand electric trucks of three

to five tons' capacity are now

sent on trips that were consid-
ered beyond the range of the

electric only a few years ago, as

it is not unusual for five-ton

brewery trucks to make a fifty-to-
sixty-mile day's run'in one round

trip from the plant. How this

is accomplished with batteries

whose normal output only suffices

to run the car forty miles on a

charge will be apparent from a

consideration of the practice of

"boosting" the battery, which is

J ® Fig. 63. Anderson Charging Regulator

nOOIl hour. Courtesy of Economy Electric Company,

Economy, Pennsylvania

Regulation of Boosting
Charge. Stress has already been laid on the fact that overcharging
at high rates is injurious to the lead battery, and is the one
thing to be most carefully avoided. However, the improved forms
of vehicle batteries now in use have considerable ability to absorb
current at high rates under proper conditions. The only factors
which act injuriously in high-rate charging are gcutxing and heating,
and these appear only when the battery is receiving more cur-
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TABLE V
Potential Boosts at Different States of Discharge

Battery Chahue

20-MlNUTE

Boost
Increase

40-MlNUTE

Boost
Increase

60-Mikito:

Boost
Increase

Battery fully discharged

22% | 38% 50%
19% 33% 42% |

Battery three-quarters discharged

Battery one-half discharged

15% 26% ' 32%

Battery one-quarter discharged

10% 16^ 20<^ 1

rent than the plates can utilize. Therefore, any current rate
which the cells will absorb without gassing is not injurious, and
it is upon this principle that boosting is applied. As an auto-
matic check upon the harmful rise of the temperature in a bat-
tery, the Anderson regulator, Fig. 63, has been devised. This is
simply a thermostat designed to cut down the charging current by
automatically inserting more resistance in the field of the generator
when the temperature exceeds 100° F., the maximum temperature
which a storage battery should ever be allowed to reach being
110° F. The device is inserted through the venthole of one of the
cells, one of its terminals being connected to the battery and the
other to the field coils of the generator. As the temperature rises,
the circuit is closed and the field strength reduced until it drops
again. It also acts as a check on the height of the electrolyte, as
it will heat up in direct proportion as the solution is low.

Possible Safe Charging Rates. The more nearly discharged a
battery is the higher charging rate it can take, and by starting the
charge at a high rate and tapering to a low rate at the end, a large
proportion of the discharge can be replaced in a very short time.
Table V gives the additional battery capacity which can be ob-
tained by constant potential boosts with the battery in different
states of discharge.

Expressed in terms of mileage, this would mean that a car,

after having given forty miles on a complete discharge, could have

its battery boosted as follows:

In 20 minutes so as to give 9 miles additional
In 40 minutes so as to give 15 miles additional
In 60 minutes so as to give 20 miles additional

Thus, by charging during the noon hour, 140 per cent of the

battery capacity is obtained in one day, bad weather conditions

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ELECTRIC AUTOMOBILES . 101

particularly representing conditions under which it is advantageous
to be able to boost the battery. A battery may have sufficient
capacity to give the required mileage under normal conditions, but
not when the roads are heavy, as after a storm, because the current
consumption is then abnormally high.

Methods of Boosting. There are several methods by which
boosting can be practically carried out, and the method chosen
depends upon the available charging facilities.

Constant- Potential Method. The ordinary incandescent lighting
circuit is supplied by a constant-potential generator, i.e., the voltage
does not vary regardless of the current utilized within the limits of
the capacity of the generator. Where conditions permit, this is the
best method because it is entirely automatic and requires little
attention. It is applicable wherever there is available a voltage of
about 2.3 volts per cell of battery — say 110 volts for 48 cells — and
the charging equipment and wiring have sufficient capacity to carry
current up to four or five times the usual charging rate. A voltage
higher than 2.3 volts per cell can be reduced by having a set of coun-
ters, m.f. cells figured at 3 volts per cell, which are always put in
series with the battery when it is boosted. This is a special type of
cell designed for this purpose. Thus if the line voltage is 110 and
the battery consists of 40 cells, a reductioi of 18 volts will be neces-
sary, and six of the counter-e.m.f. cells will be required.

With the charging voltage thus fixed at 2.3 volts per cell, a
battery in any state of discharge can be put on charge and will
receive in a short time a large proportion of the discharge which has
been utilized. The current input will taper automatically from
a high rate at the start to a low rate at the finish, and no attention
or adjustment is required. The cells will not reach the free gassing
point or, under normal conditions, a high temperature and, there-
fore, no harm will result from their being inadvertently left on charge.
Approximate Constant-Potential Method. This is employed
with a fixed resistance in series with the battery; and when the time
available for boosting is one hour or less, the following method is
often the simplest. Connect a rheostat in series with the battery
and adjust the resistance so that the voltage across the battery
terminals corresponds to that given as follows for the approximate
number of cells.

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Number of Cells

Voltage at Battery
Terminals

48
44
42
40
38

110
98
92
86
80

Charging current (amperes) = ;

The circuit can then be left without attention for an hour or so,
and the current will taper off as the voltage of the battery rises. The

table is figured for a line voltage of r^, and the .voltages given are

to<) high for a boost of more than one hour's duration.

Constant-Current Method. In some cases it is more convenient
to boost at a constant rate of current, and, as there is usually a lim-
ited time available, it is desirable to know under any given condi-
tions what rate is safe. This may easily be determined as follows:

ampere hours already discharged
1 + (hours available for boosting)

This gives the maximum current which can be employed for the time
specified without the cells reaching the gassing point. The method
is most conveniently employed where the car is equipped with an
ampere-hour meter. For example, 100 ampere hours have been
discharged and there is one hour available for boosting. Then

Charging current = - — - = 50 amperes

In general, this method will not put in as much charge in a
given time as the constant-potential method, and the current must
not be continued beyond the time for which the rate is figured, as
injurious gassing and heating will result. When a considerable
period is available for boosting, and it is convenient to regulate
the current at intervals, a greater amount of charge is possible by
dividing the time into several periods and regulating the amount
of current for each period separately. It will usually be found
that one of the methods outlined will be available, but to obtain the
advantages of boosting without injury to the battery, gassing must
be avoided and the temperature of the cells kept below 110° F.

Table VI is based upon the above formula and saves the neces-
sity of making calculations.

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103

TABLE VI
Boosting Rates*

[

— —r-. : = — t

Time Available

. fob Boosting

Ampere

Houaa

yi hour

H hour

$4 hour

1 hour

\% hours

1 x /i hours 1 % hours

2 hours

Discharged

Amperes

100

110

120

130

104

140

112

150

120

100

160

128

106

170

136

113

180

144

120

103

190

152

127

108

200

160

133

114

100

210

168

140

120

105

220

176

147

126

110

230

184

153

131

115

102

240

192

160

137

120

106

250

200

167

143

125

111

100

♦Courtesy of Electric Storage Battery Company.

Explanation. In the left-hand column find the figure nearest to the
ampere hours discharged from the battery; follow across to the column headed
by the available time. The figure at this intersection is the current to be used.

Example. Ampere-hour meter reading, 103 ampere hours discharged;
time available for boosting, one hour. Start at 100 in the left-hand column;
follow across to the column headed 1 hour and find 50, which is the current to be
used.

CARE OF BATTERY

Importance of Careful Attention to Battery. While it would
appear that the remainder of the car calls for no little attention, the
amount, exclusive of that which must be given the battery, is very
slight as compared with that necessary to maintain either a gasoline
or steam automobile. The battery is naturally the chief factor in
any electric automobile and, as its initial cost is no small fraction of

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the total cost of the vehicle, its proper maintenance is a matter of
economy no less than of good service. More so than any other
piece of electrical apparatus, a storage battery has a definitely deter-
mined life. Regardless of the care given it, the active period of
service of which it is capable may be expressed as a certain number
of discharges. By properly looking after it, this number may be
realized, and a greater percentage of the energy put into it taken
advantage of. In other words, its life will not only be longer, but
its efficiency much higher during that period as the result of proper
care. It is difficult to impress upon the uninitiated owner the impor-
tance of paying strict attention to the letter of instructions con-
cerning the care of the storage battery in a vehicle, and this accounts
to a greater or less extent for those cases of dissatisfaction with the
electric vehicle which occasionally come up. For the particular
service for which it is designed, the electric vehicle has no superior,
but its advantages are only to be enjoyed to the greatest degree by
giving it regular and proper attention, and fully 90 per cent of this
attention must be devoted to the battery.

It must be borne in mind that the storage battery in an electric
vehicle must work under conditions which are diametrically opposed
to those which make for high efficiency in such a piece of apparatus,
for it is always subject to the destructive effects of vibration and
jolting. To secure that degree of conductivity which is essential
to high capacity, the active material should be loose and porous,
but in order to fit it for vehicle service the plates must be made rigid
and unyielding. For the same purpose, an ample quantity of elec-
trolyte, so disposed as to permit of rapid circulation, should be
employed, but the necessity of not only keeping the plates apart,
but also of preventing any movement whatever, compels the use of
separators which occupy space that should be given to the solution.
The need for compactness is also against the latter. These conflict-
ing requirements are pointed out here merely as an indication of the
difficulties that must be met. The aim of storage-battery manu-
facturers has been to meet vehicle conditions, without impairing
the electrical efficiency of the battery any more than has been
absolutely necessary.

Limits of Discharge. To obtain the best possible service from
a battery, it should never be discharged below 1.70 volts per cell,

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or 41 volts for a 24-cell battery, this being measured when the vehicle
is running at full speed on the level, all of the cells then being con-
nected in series. If the average discharge rate is for any reason
considerably more than the normal rate of the battery, the working
voltage will be correspondingly lowered, so that a slightly lower
limiting voltage is permissible. In general, however, it is safer not
to go below 1.70 volts per cell, except momentarily, as when starting
or on a grade. The battery should never be allowed to stand fully
discharged, as local action and sulphating rapidly take place.

Sulphating. ' It has been pointed out in the introductory sec-
tion of Part I that during each discharge both the positive and
negative plates become covered with lead sulphate, but in the
normal use of the battery the sulphate is converted during the
following charge to lead peroxide on the positive plate and spongy
metallic lead on the negative. Should the battery be allowed to
stand in a discharged state for any length of time, however, the lead
sulphate on the plates will harden, causing what is usually termed
"sulphating". When the battery is put into use again this will
result in loss of capacity, buckling, shedding of the active material
from the positives, and greater heating of the cells due to increased
internal resistance. Sulphating can be remedied by continuous
charging for a long period at a low rate, i. e., for 24 to 36 hours, or
longer, at a rate not exceeding 10 to 15 per cent of normal. This
loosens the sulphate and reconverts it as previously mentioned, thus
restoring the plates to their normal condition. The length of time
and the charging rate necessary to effect a complete restoration will
be governed by the extent to which sulphating has taken place, and
the loss of capacity will afford a fairly approximate indication of
this. The great loss of capacity, with the possible total ruin of the
battery if allowed to go on long enough, explains [the emphasis laid
on the instructions — never let the lead-plate battery stand discharged.

When it is not convenient to have the battery fully charged at
once, a partial charge should be given and completed as soon there-
after as possible, and before the battery is again discharged. When
the vehicle is out of service, the battery should be given a freshening
charge at least every month, and every two weeks would be pref-
erable. A cell standing idle tends to discharge itself, owing to the
unstable nature of the chemical compounds which represent the

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stored energy; and if left in a discharged condition for any length
of time, the cell will deteriorate far more than in the most active
service under proper conditions.

As an additional indication of the relative condition of the cells
in a battery, the voltage of each cell should be taken with a low-
reading voltmeter — i. e., one calibrated to read to 3 volts by tenths —
at least once every two weeks, and the specific gravity of the elec-
trolyte of each cell should also be tested at about the same interval.
The voltage readings in question should be taken just before the
end of the, prolonged charge mentioned, or just before the end of
a complete discharge, and always with the current flowing. Should
any of the cells read lower than the average, it is an indication of
trouble and they should be treated as explained later.

Condition of the Cells. Electrolyte. One of the cardinal points
to be observed in the care of the battery is to keep the plates covered
with electrolyte to the depth of at least half an inch, but no more.
Except where .the level has been lowered by slopping or leaking, any
loss should be replaced by the addition of distilled water. The water,
bdng the more volatile part of the solution, is subject to evapora-
tion, particularly on account of the increase in temperature due to
the charge. The loss by evaporation causes a rise in the specific
gravity, which would not be remedied by the addition of electrolyte.
The latter is only necessary where the loss has been that of the
solution itself, as from slopping or leakage. Water to replace
evaporation should always be added at the beginning of a charge.

, As it is not always convenient to obtain distilled water and as
neither rain water nor melted artificial ice is available when wanted,
a small gas-heated still has been placed on the market for this pur-
pose. This is known as the "Peerless" water still, and is made in
two or three sizes adapted to the use of private and public garages.
It consists of a Bunsen burner for gas, an evaporating chamber
directly over it in the form of a cowl, and a condensing tube which
is cooled by passing the cold feed water around it. The smallest size
has a capacity of one-half to one gallon )f distilled water per hour
and, once adjusted, will operate continuously without further atten-
tion. It is designed to be fastened to the wall in any convenient
location, and only requires connecting with the gas- and water-
supply pipes to put it in operation.

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Connections. Attention should be paid to keeping the con-
nections and terminals, the outside of the jars, the straps, batten-
trays, and the battery space in the vehicle dry and free from dirt
and acid. This is a far more important precaution than may appear
at first sight, for if not attended
to, corrosion and loss of capacity
will result. In storage batteries
for starting and lighting gasoline
cars, this difficulty has been ob-
viated to a considerable extent
by the use of a special form of
cover incorporating an expansion
chamber.

CLEANINO OR WASHING A
BATTERY

Methods of Avoiding Inju-
rious Effect of Sediment in Cells.

During the normal use of a bat-
tery, the gradual wear of the
plates results in a deposit of sedi-
ment which collects in the bot-
tom of the jar where a space is
provided to hold a considerable
quantity before it accumulates
sufficiently to touch the bottom
of the plates, Fig. 64. The rate
at which sediment accumulates
depends very largely upon
whether the battery is charged
properly or not. If the battery Fig M E iba on with Low Mud space

is Charged in SUch a Way as tO and Bolted Connections

cause excessive gassing, the gas coming out of the pores of the positive
plates tends to soften and dislodge the active material. This is the
reason the charging current must be reduced as soon as the cells
begin to gas freely. If a battery is constantly undercharged, the
sulphate which is thus allowed to accumulate in the negative plates
will eventually lose its cohesion and the surface will gradually wash

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away, falling to the bottom of the jar as a deposit of sediment. It
is neither necessary nor desirable that every charge be carried to com-
pletion, but in order to make certain that the plates do not become
sulphated, a weekly "equalizing" charge is given.

If a battery has been neglected so that cleaning is not undertaken
until the deposit of sediment has actually reached the plates, the

sediment is then deposited much
more rapidly. Permanent injury
and decreased life of the plates
result. The Elba cell, Fig. 65, is
designed with a mud space suffi-
ciently high to accommodate the
entire deposit of sediment occur-
ring during the life of the elements,
so that washing is not necessary
in this type of cell, the jars only
being cleaned out when the ele-
ments are renewed.

Since the conditions under
which batteries are operated vary
so widely, the best method of
determining when it will be nec-
essary to clean a battery is to
remove the element from one of
the cells after about 100 to 150
charges have been given it, to
determine the rate at which the
sediment is accumulating. From
the amount of sediment compared
with the depth of the space in the
bottom of the jar, it is possible
to estimate when cleaning will

Fig. 05. Elba Cell with High Mud Space . - . , ,

be required. Always clean a
battery before there is any possibility of the sediment reaching the
bottoms of the plates. To insure this, the entire depth of the space
should not be taken as a fixed quantity in estimating the rate of
sediment deposit, but a margin of safety of § to £ inch should be
allowed, since the jolting of the vehicle is apt to bring the sediment in

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contact with the plates and short-circuit them momentarily, if allowed
to rise any closer. At the expiration of the estimated time, cut out a
different cell and examine it to determine definitely if the time for
cleaning has arrived.

Various Conditions to be Found. The method of procedure in
cleaning will depend upon the condition of the battery, as follows:

1 . If the battery has not been allowed to become sulphated and the sediment
has not reached the bottoms of the plates, its cleaning is a comparatively simple
operation and the only preliminary treatment is to first bring the battery to a
state of full charge.

2. If the battery is in a sulphated condition due to improper charging,
but the sediment has not reached the bottoms of the plates, it should be given
the treatment detailed under "Restoring a Sulphated Battery", before cleaning.

3. If the sediment has been allowed to reach the bottoms -of the plates
because cleaning was not carried out soon enough, the battery will, as a matter
of course, be in a sulphated condition by reason of the short-circOits through the
sediment. Such a battery must first be cleaned as described below and after-
ward given the treatment referred to under "Restoring a Sulphated Battery".
This treatment cannot be given successfully in its short-circuited condition.

Materials to Have on Hand. Before starting the work of clean-
ing the battery, have on hand a set of new wood separators and suffi-
cient new acid of 1 .300 specific gravity with which to mix new elec-
trolyte. Many of the old rubber separators can be used again, but,
as is the case when renewing the entire element of the cell, about
twenty-five per cent of new rubber separators should be at hand for
replacements. Three or four extra jars and covers should also be at
hand, and the trays should be examined to note if their condition is
such that they may be depended upon to last the remaining life of the
cells. If new trays are necessary, see instructions under "Renewal".

In fact, as the process of cleaning is, to a large extent, the same as
that of renewing the elements, the instructions for dismantling the
battery are the same. All the connectors should be removed by
pulling or drilling. The jar covers should be lifted by running a hot
putty knife around their edges, and the covers should be washed in
hot water and then stacked one on top of the other with a heavy
weight on them to press them flat.

Treating the Plates. Lift all the jars out of the trays, leaving
their elements in the electrolyte. The trays can then be examined,
and, if usable, given the treatment described in connection with
renewals to neutralize any acid in the wood. Proceeding further,

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110 ELECTRIC AUTOMOBILES

one cell should be treated at a time. The element is pulled out with
the aid of pliers, meanwhile holding the jar with the feet; it is laid on
the bench and the plates spread slightly to permit of removing the
separators, taking care not to injure the rubber sheets, Fig. 66.
Separate the positive group from the negative. If the active material
of the negative be swollen beyond the surface of the grid, press it back
into position before it has a chance to dry by placing boards of suit-
able thickness between the plates and carefully squeezing the group
between heavy boards in a vise or press, as shown in Fig. 67. Boards
of sufficient size and thickness must be used between the plates or

Fig. 66. Removing Old Separators from

Elements Fig. 67. Pressing Negative Group

Courtesy of Electric Storage Battery Company, Philadelphia, Pennsyltania

breakage will result. Charged negative plates, when exposed to the
air, will become hot in a short time and in this event should be allowed
to cool before reassembling. Remove any loose particles adhering
to the positive plates by passing a smooth wooden paddle over the
surface, but do not wash the positive plates.

Washing or Renewing Separators and Assembling Cells. Wash
all the sediment out of the jar to have it ready for the element when
reassembled. Wash and save the rubber sheets, but throw away
the old wood separators. "Wash" in this connection means to place
under running water that is known not to contain any injurious
impurities, for fifteen minutes or more. Reassemble the positive

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and negative groups with the plates on edge in order to insert the
separators. Place a rubber separator against the grooved side of a
wood separator, Fig. 68, and insert a positive plate near the center of
the element. The rubber sheet must be against the positive plate
and the wood separator against the negative plate. In this manner,
insert separators in all the spaces, working in both directions from
the center, exactly the same as in renewing the element. An omitted
separator means a short-circuited cell.

The separators should be practically flush with the bottoms of
the plates to bring their tops against the hold-down below the strap,
and must extend to, or beyond, the
side edges of the plates. Grip the
element near the bottom to prevent
the plates from flaring out while
placing in the jar. Fill the cell to
within i inch of the top of the jar,
using electrolyte of a specific grav-
ity of 1.250, unless the battery is
in a sulphated condition, in which
case, use water. After all of the
cells have been given the same treat-
ment and reassembled, place them
in the trays in the proper position,
so that the positive of each will be
connected to the negative of the adjoin-
ing cell, and connect temporarily
by pressing the old connectors into

*^ ' Fig. 68. Wood and Rubber Separator

Charging Process after Wash-
ing Battery. Put the battery on charge at the regular finishing rate
and, after charging about fifteen minutes, note the voltage of each
cell, recording these readings as mentioned in connection with renew-
als. This is to insure the cells having been correctly connected with
regard to their polarity. If this is the case, each cell should read
above 2 volts; any cell with a lower reading is likely to have been con-
nected backward. When the cells begin to gas freely and uniformly,
take and record a hydrometer reading of each cell and the tempera-
ture of one cell. Reduce the current to one-half the normal finishing

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rate. Should the temperature reach 100° F., reduce the charge or
interrupt it temporarily so as to prevent the cells getting any hotter.
Both hydrometer and temperature readings must be taken at regular
intervals, say four to six hours apart, to determine if the specific
gravity is still rising or if it has reached its maximum. Continue
the charge and the readings until there has been no further rise in any
cell during a period of at least twelve hours. Maintain the height
of the electrolyte constant by adding water after each reading. (If
water were added just before taking the reading, it would not have
time to mix with the electrolyte, and the reading would be misleading.)
Should the specific gravity rise above 1.300 in any cell, draw off
its electrolyte down to the level of the top of the plates and refill with
as much water as possible without overflowing. Continue the charge,
and if the specific gravity again exceeds 1.300 all the electrolyte in

that cell should be dumped
out and replaced wnth
water, then continue the
charge. The charge can
be considered complete
only when there has been
no rise in the gravity of
any cell during a period
of at least twelve hours of
continuous charging.
Upon completion of the charge, the specific gravity should be
adjusted to its proper value (1.270 to 1.280), using water or 1.300
acid as may be necessary, and the electrolyte level adjusted to a
uniform height of J inch above the plates.

Discharge the battery at its normal discharge rate (see
"Renewal") to determine if there are any low cells caused by defective
assembly, which should immediately be corrected. Recharge and
then remove the temporary connectors. When the cells are arranged
in their trays, as shown in the sketch made before the battery was
taken apart, Fig. 69, put the rubber covers in place, wipe the inside
edges of the jars dry, and seal with the compound supplied for this
purpose. Heat the sealing compound, taking care that it is not
allowed to burn, and apply around the edges of the cover, smoothing
down with a hot putty knife.

Fig. 60. Diagram of Battery Connections Drawn
before Dismounting

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It is preferable to use new connectors, but if these have not been
provided, the old ones may be replaced if sufficient care has been taken
in removing them. Before putting the connectors in place, scrape
the posts clean and smooth. In using old connectors, clean out the
eyes with a knife blade. When the connectors have been put in place,
tap them down firmly to insure good contact. Before reburning the
connectors in place, test each cell with a low-reading voltmeter to
make certain that the cells have all been reconnected in the proper
direction, i.e., that their polarity has not been reversed. It is not
sufficient to note that the voltage of the cell is correct, i.e., 2 volts
or over; but care must be taken also to note that it is in the right
direction. With a voltmeter having a needle that can move in both
directions from zero, one polarity will be evidenced by the needle
moving over the scale to the right of the neutral line, while if the
polarity be reversed, the needle will move to the left, so that a cell
having the proper polarity should be tested, and then, to be correct,
all the remaining cells should cause the needle to move in the same
direction and read to approximately the same voltage when the
instrument leads are held to the cell terminals in the same way for
each. Where the voltmeter needle can move only in one direction,
i.e., to the right, a change of polarity will be indicated by the needle
of the instrument attempting to move to the left and, in so doing,
butting up against the stop provided to prevent this.

Complete the reassembly of the battery by burning the connec-
tors of all the cells together, detailed instructions for this being given
under "Lead Burning". The cleaning of a battery which has been
properly charged and in which the sediment has not been allowed to
reach the bottoms of the plates is a simple operation compared with
treatment necessary to clean and restore a battery which has been
neglected. The process of cleaning is also frequently referred to as
"washing the battery", which refers to the internal treatment
already outlined, and not to washing it outside.

// is of the utmost importance that the battery be cleaned before the
sediment is allowed to accumulate to a point where it reaches the plates.

Replacing a Defective Jar. When a cell requires the addition of
distilled water more frequently than the other cells in the same bat-
tery, or does not test to the same specific gravity as the others, it is
usually an indication that there is a leak in the jar. Failure to give

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114 ELECTRIC AUTOMOBILES

, Fig. 70. Drilling off Connectors
Coutiety of Electric Storage Battery Company, Philadelphia, Pennsylvania

Pig. 71. Lifting Cell out of Tray
Courtesy of Electric Storage Battery Company, Philadelphia, Pennsylvania

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ELECTRIC AUTOMOBILES 115

the same gravity reading is not always proof of this condition, as the

cell may be low from other causes, but the loss of electrolyte is certain

evidence of it. The only remedy

is to replace the jar at fault.

While the following directions

for doing this apply to the

Exide battery in particular, they

will be found equally applicable

to all other makes.

After locating the jar at fault,
first mark its connectors so that there
will be no mistake in replacing them
the same way. With a f -inch bit or
twist drill of the same size, drill the

connectors centrally in the top of the Fig. 72. Softening Sealing Compound on Cell
enlarged ends joined to the two cells

adjacent to the jar that is to be replaced, Fig. 70. Lift the complete cell out
of the tray, Fig. 71, and with an ordinary gasoline blow torch warm the sides
of the jar around the top to soften the
sealing compound that holds the cover,
Fig. 72. Grip the jar between the feet, take
hold of the two connectors, and pull the ele-
ment almost out of the jar, Fig. 73; then grip
the element near the bottom in order to keep
the plates from flaring out, Fig. 74, while trans-
ferring to the new jar, taking care not to let
the outside plates start down over the outside
of the jar, Fig. 75. After the element is in the
new jar, reseal the cell by pressing the sealing
compound into place with a hot knife. Fill
the cell with 1.250 electrolyte to the proper
point, the old electrolyte being discarded.

Before replacing the connector, clean
both the post and the inside of the eye of the
connector by scraping smooth with a knife.
When the connector has been placed in posi-
tion, tap it down firmly over the post to insure
good contact. To complete the connection,
melt the lead of the connector and the post at
the top so that they will run together, and,

while the lead is still molten, melt in more Fig. 73. Lifting Element out of Jar
lead until the eye of the connector is filled,

Fig. 76. This is termed lead burning and is described at greater length in :i
succeeding section. Where no special facilities are at hand for carrying it out,
it may be done with an ordinary soldering copper. The latter is brought to :v
red heat so that all the "tinning" is burned off and no flux of any kind is used.

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ELECTRIC AUTOMOBILES

Fig. 74. Gripping Element near Bottom Fig. 75. Installing Element in Jan

to Keep JPlatce from Flaring out

Courtesy of Electric Storage Battery Company, Philadelphia, Pennsylvania

The method of handling the iron and the lead-burning strip to supply the extra
metal required to fill the eye is shown in Fig. 77.

Put the battery no charge, and when the cells begin to gas freely, reduce
the current to half the "finishing" rate given on the battery name plate, and

Fig. 76. Reburning Cell with Carbon Arc
Courtesy of Electric Storage Battery Company, Philadelphia, Pennsylvania

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ELECTRIC AUTOMOBILES 117

<»harge at this rate as long as there is any rise in gravity in the electrolyte in this
or in any of the other cells. The maximum gravity has been reached when there
has been no rise for a period of three hours. If the gravity of the cell having
the new jar is then over 1.280, draw off some of the electrolyte and replace with

Fig. 77. Reburning Cell with Soldering Iron After Replacements Previously

Described Have Been Made

Courtesy of Electric Storage Battery Company, Philadelphia, Penntylvania

distilled water. If the gravity is below 1.270, draw off some of the electrolyte
and replace with 1.300 electrolyte. If necessary to put in 1.300 electrolyte, allow
the battery to continue charging for about one-half hour longer at a rate sufficient
to cause gassing, which will cause the stronger acid to become thoroughly mixed
with the rest of the electrolyte in the cell.

COMPLETE RENEWAL OF BATTERY

Materials Needed. In garages caring for a number of electric
vehicles, it is customary to carry out all the repair work demanded by
the batteries, including the complete renewal of the cells. The

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118 ELECTRIC AUTOMOBILES

material is ordered from the maker of the battery, and the form in
which it is sent for will depend upon the facilities at hand. The
following material is required for a complete renewal: positive
groups, i.e., plates already burned to straps, or positive plates and
positive straps, negative groups or negative plates and negative straps,
connectors, burning strip, wood separators, rubber separators, rubber
jars, rubber covers, rubber plugs, sealing compound, electrolyte,
trays, handles, and terminals.

Note the number of plates and their size and type, this informa-
tion usually being given on the plate on the tray. Unless facilities
are at hand for burning the plates into groups, it is better to order
groups. If the plates are ordered loose, positive and negative straps
must also be ordered, and, in any case, the following information must
be given : size and type of plate, number of plates per cell, length of
jar outside, width of jar outside, height of jar outside, height from top
of rib of jar. In ordering connectors, give the distance between the
center of the eyes, noting if more information than the size is
required. Two pounds of burning strip is sufficient for burning the
connectors of an ordinary battery; when loose plates are ordered,
provide one pound additional for each fifty plates. The clippings
from the plate lugs can be melted down and cast into strips for this
purpose, if desired.

Where the separator type cannot be identified by name or num-
ber, send samples of the old ones to the manufacturer. All new
wood separators will be necessary, and in ordering these it is advisable
to provide at least 10 per cent more than are actually required. Most
of the old rubber separators can be used again, but it is well to provide
about 25 per cent of new ones. Order three or four extra jars and
covers, giving the dimensions as already noted. A new set of rubber
plugs will usually be found advisable. The average pleasure-car
battery or that of a light truck requires about J pound of sealing
compound per cell; this compound is supplied in 5-, 10-, and 30-pound
tins. In dismantling the old battery, measure the amount of electro-
lyte necessary in one cell to bring its level \ inch over the plates, and
order sufficient 1.300 electrolyte to fill all the cells. Electrolyte is
usually longer in transit than any other material, so this must be
allowed for. In ordering new trays, make a sketch showing the
inside and outside length, width, and depth, and whether the sides

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are solid or slatted, also specify the size and type of handles and their
position. When obtained locally, trays should be well painted with an
acid-resisting paint. Upon receipt of the material, immediate atten-
tion must be given the wood separators to prevent their drying out.
Wood separators must always be kept wet.

Dismantling the Battery. To dismantle the old battery that is
to be renewed, first remove all the connectors by drilling centrally in
the top of the enlarged ends, as already explained in connection with
the replacement of a jar. Where
much of this work is done, a device
termed a "connector puller' ' may be
obtained from the battery maker.
After removing the connectors, lift
all the covers by running a hot
putty knife around the sealed edges
and, after they have been taken out,
clean all the compound off them and
place them in hot water. This will
clean the acid from the covers and
also soften them. In this condi-
tion, stack the covers and place a
weight on them to keep them flat.

Lift all of the cells out of the
trays. When making a complete
renewal, the old trays are seldom
worth saving, but if they are to be
used again, immerse them in a barrel
of water in which about 10 pounds

Of bicarbonate Of Soda (common Fig. 78. Lifting Element out of Jar

with Pliers ,

baking soda) has been dissolved,

to neutralize the acid in the wood. After drying, they will be
ready for use. Grip one jar firmly between the feet and lift out
the element with the aid of two pairs of pliers, Fig. 78. Spread
the plates slightly and remove the wood and rubber separators,
taking care not to injure the rubber sheets. Throw away the
old wood separators and scrap the old plates. Wash all sedi-
ment out of the jars to have them ready for assembling the new
elements.

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120 ELECTRIC AUTOMOBILES

Burning Groups. When new plates and straps have been
ordered separately and are to be burned into groups, first provide a

"burning box", as shown in
Fig. 79. Scrape the plate lugs
clean and bright and arrange the
plates as shown in the burning
box. The height of this box
should be J inch less than the dis-
tance from the top of the ribs of
the rubber jar to the top of the
jar. The burning iron, which
acts as a space between the plates
and as a support for the strap,
should be made of iron J inch
thick and slotted to fit the plate
lugs. This J inch in addition to
the height of the burning box

Fig. 79. Assembling Group in Burning Box wil j g j ye ^ r j ght he j ght fop ^

strap, the bottom of which should be f inch below the top of the jar.
^ Place the strap over the plate lugs to rest on the burning iron.

The plate lugs should be trimmed about flush with the top of the strap.

After burning, cut off the pro-
jecting ends of the negative
straps so that the elements may
enter the jars, Fig. 80. It is not
necessary to clip off the ends of
the positive straps.

Before dismantling the old
battery, a sketch of the position
and polarity of the cells in each
tray should be made, indicating
the position of the tray terminals
and their polarity, that is, wheth-
er the positive is to the right or

Ffc. SO. Clipping off End of Negative Strap left slde ° f the tr *V when fftcin g

the terminal end, Fig. 69.
Reassembling the Cells. Assemble the new positive and nega-
tive groups with the plates on edge in order to insert the separators.

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ELECTRIC AUTOMOBILES 121

Place a rubber separator against the grooved side of a wood separator,
Fig. 68, and insert between a positive and a negative plate near the
center of the element. The rubber sheet must be against the positive
and the smooth side of the wood separator against the negative,
Fig. 81. In like manner, insert separators in all the spaces, working
in both directions from the center. Leaving out a separator means a
short-circuited cell. The separators should be practically flush with
the bottom of the plates to bring their tops against the hold-down
below the strap and must extend to or beyond the side edges of the
plates. Grip the element near the bottom in order to prevent the
plates from flaring out when placing the (element in the jar.

Fill the cells to within J inch of the top of the jars, using electro-
lyte of a specific gravity of 1.300 and allow the cells to stand from

Fig. 81. Installing Separators
Courtesy of Electric Storage Battery Company, Philadelphia, Penntyltania

twelve to twenty-four hours before starting to charge. After all the
cells have been assembled, place them in trays in the proper position,
so that the positive of each will be connected to the negative of the
adjoining cell and connect temporarily by pressing the connectors into
position by hand, using the old ones if available.

Initial Charge. Give the initial charge by putting the battery
on the regular finishing charge rate. After charging about thirty
minutes, note the voltage of each cell, recording these readings as
shown in the first column of the form, Fig. 82.

This is to insure that all the cells have been properly connected
up, i.e., in the direction as to polarity. If they have been properly

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122 ELECTRIC AUTOMOBILES

connected, each cell will show in excess of 2 volts. Any cell showing
less than 2 volts is probably connected backward and should be
inspected. Then reduce the charging current to as near one-half of
the regular finishing rate as the charging apparatus will permit
Select one cell near the center of the battery, which will be the

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Pilot Cell No. /*< '^ v

Fig. 82. Specimen Battery Charging Record
Courtesy of Electric Storage Battery Company, Philadelphia, Pennsylvania

"pilot cell" throughout the charge. Record readings of time and
current and the specific gravity and temperature of this pilot cell, as
indicated in the lower form, Fig. 82, at intervals of from six to twelve
hours. Should the temperature at any time reach 100° F., reduce
the current or temporarily interrupt the charge so as not to exceed
this temperature.

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ELECTRIC AUTOMOBILES 123

Maintain the level of the electrolyte by adding water as neces-
sary. Never add water just before taking hydrometer readings
because it would not have time to mix with the electrolyte and would
give a misleading reading. Hydrometer readings should be corrected
for any substantial change in the temperature, as detailed in the
section on the Use of the Hydrometer, Part I. When the gravity of
the pilot cell has shown no further rise for a period of twenty-four
hours, record hydrometer readings of each cell in the column marked
"specific gravity", Fig. 82. In recording readings, start at the posi-
tive terminal of cell No. 1, and follow the direction of the electric
circuit. Individual cell readings should be recorded at intervals of
about tw r elve hours to insure that each reaches a maximum. Bear in
mind that the object of the initial charge is to remove all acid com-
bined in the plates.

Do not stop the initial charge just because a specific gravity of
1.270 or 1.280 may have been reached, because this may not be the
maximum. Continue to charge as long as the gravity continues to
rise. The charge can be considered complete only when there has
been no rise in the gravity of any cell during a period of twenty-four
hours of continuous charging. In case the gravity rises about 1.290
in any cell, draw off its electrolyte down to the top of the plates and
replace with water, saving this electrolyte for adjusting the specific
gravity of the cells as follows: Upon completion of the charge adjust
the specific gravity to its proper value (1.270 to 1.280), using water
or electrolyte as may be required, and bring the level of the electrolyte
to a uniform height of \ inch above the tops of the plates. Some
variation on the specific gravity among different cells is to be expected,
since the amount of water in the separators and difference in level
when filled affect this.

Importance of Initial Charge. The foregoing outline of procedure
is based on the assumption that the initial charge is continuous, since
this will require the shortest time. It is especially desirable that the
first twenty-four hours of the charge be given without interruption,
even if the entire charge cannot be made continuous. Where there
are interruptions, the twenty-four hours of maximum gravity must
be actual charging time and must not include any idle time. The
accuracy of the ammeter should be checked for the current readings
used.

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124 ELECTRIC AUTOMOBILES

A battery which has not received sufficient initial charge cannot
be expected to give satisfactory service and life. Therefore, in case
of any doubt, prolong the charge rather than run the chance of stop-
ping it too soon. As a further precaution, it is advisable to see that
the first few charges after the battery goes into service fire somewhat
prolonged.

Test Discharge. After giving the battery its initial charge,
it is customary to make a test discharge and, if necessary, recharge
and make a second test discharge, to avoid the possibility of the bat-
tery being put into service with any low cells in it caused by defective

[Fig. 83. Wiring Diagram for Battery Test Discharge, Using Rheostat

assembly. The test is also made to determine its capacity. Capacity,
however, does not necessarily indicate the completeness or incom-
pleteness of the initial charge. The only sure indication is the maxi-
mum specific gravity reached in each cell. This test discharge should
preferably be made at the normal discharge rate of the battery and
may be carried out with the aid of a rheostat, as shown in Fig. 83, or,
where one of this or similar type is not available, by constructing an
emergency water rheostat, as shown in Fig. 84. The container should
preferably be a wooden tub or an earthenware jar, as a metal container
naturally would not be suitable, since the current could then follow
a shorter path from the electrodes to the container instead of being
compelled to pass through the solution between the electrodes. The

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ELECTRIC AUTOMOBILES 125

solution employed is weak electrolyte, while the electrodes may be
either strips of metal or pieces of carbon. They should be mounted
on a piece of board so that the distance between them may be
ud justed, as the amount of current that flows will depend upon this
distance. Separating them further will decrease the amount of
current passing, while bringing them closer together will increase it,
the rate of discharge being shown by the ammeter. In case the rate
is too high at the maximum distance to which the electrodes can be
separated, weaken the electrolyte solution of the rheostat by adding
more water or, if necessary, make it plain water. If the rate of dis-

Fig. 84. Wiring Diagram for Battery Test Discharge, Using Water Rheostat

charge is insufficient even when the electrodes are brought close
together, strengthen the electrolyte slightly. A convenient form for
keeping the discharge record is shown by Fig. 85. Should a second
test discharge be made, the capacity will be less than the first, but,
after several discharges, the battery will not only recover but will
exceed its first capacity.

Recharging. The battery should then be fully charged, and the
specific gravity of the electrolyte adjusted to the proper point. On
this occasion, all the precautions mentioned in connection with the
initial charge and the polarity of the charging connections must be

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126 ELECTRIC AUTOMOBILES

observed. The battery should then be fully discharged. (Fig. 83
shows the method of connecting the battery to discharge through a
rheostat, while the water resistance described is illustrated by Fig. 84.)

t*xip~'1-'f/Y DISCHARGE »*___/

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REMARKS.

Fig. 85. Specimen Battery Discharge Record
Courtesy of Electric Storage Battery Company, Philadelphia, Pennsylvania

If a suitable resistance is not at hand for this purpose, a water resist-
ance may easily be made as follows:

Take a vessel of wood, or any other material except metal, and
fill it almost full of a diluted solution of sulphuric acid and water. Con-
nect the ammeter to one plate of metal and the battery to a second
plate of metal, both of which should be suspended in the solution, care

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ELECTRIC AUTOMOBILES 127

being taken to prevent the current from passing from one plate to the
other except through the solution. The remaining terminal of the
battery and of the ammeter should be connected together. There is
then a complete circuit through the improvised resistance, and the
strength of the current may be varied by placing the plates nearer
together or farther apart, or by adding acid to the solution, either of
which operations will decrease the resistance. This should be adjusted
until the ammeter shows that the battery is discharging through the
resistance at its normal rate. After cleaning, the capacity of a battery
may not be as great as it was previous to the operation until it has had
several charges and discharges. While dismantled, the wood trays
of the battery should be well rinsed with a strong solution of bicar-
bonate of soda and water in order to neutralize any acid on them.
After that, they should be well rinsed with water and, when dry,
painted with acid-resisting paint.

PUTTING BATTERY OUT OF COMMISSION

Methods of Storage. When a battery is not to be used for some
time, it must be specially prepared before being stored. There are
two general methods of preparing a battery for storage, one known as
"wet storage" and the other as "dry storage", the method adopted
depending upon the condition of the battery and the length of time
it is to be out of commission. The wet-storage method is usually
applied to any battery that is to be out of commission for less than a
year, provided its condition is such that it will not soon require repairs
necessitating dismantling it. The dry-storage method is used for any
battery that is to be out of commission for more than a year, Tegardless
of its condition, and it is also applied to any battery that will shortly
require repairs necessitating its dismantling.

Wet Storage. Examine the condition of the plates and separators
and also the amount of sediment in the bottom of the jars. If it is
found that there is very little sediment and the plates and separators
are in sufficiently good condition to give considerable additional
service, the battery may be put into wet storage by giving it an
equalizing charge and covering it to exclude dust. Replace evapora-
tion periodically by adding distilled water to maintain the level of the
electrolyte § inch above the top of the plates. At least once every
four months, charge the battery at one-half the normal finishing

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128 ELECTRIC AUTOMOBILES

rate until all the cells have gassed continuously for at least three hours.
Any cells not gassing should be examined and the trouble remedied.

Dry Storage. When the examination shows that the battery
will soon require repairs that necessitate dismantling, it should be put
into dry storage. Dismantle the battery in accordance with the
instructions given in a preceding section under this head, first making
the sketch of the layout and connections as there illustrated. If the
positive plates show much wear, they should be scrapped; if not,
remove any loose particles adhering to them by passing a smooth pad-
dle over the surface but do not wash the positive plates. Charged
negative plates will become hot in a short time when exposed to the
air; they should be allowed to stand in the air until cooled.

Empty the electrolyte out of all the jars into a glazed earthenware
jar or lead-lined tank and save it for giving the negative plates their
final treatment before storage. Wash all the sediment out of the
jars; wash the rubber separators carefully, dry them, and tie them in
bundles. Place the positive groups in pairs, put them into jars, and
store them away. Place the negative groups together in pairs, put
into the remaining half of the jars, cover them with the electrolyte
saved for the purpose, and allow them to stand in it for five hours at
least. Then pour off the electrolyte, which may now be discarded,
and store away the jars containing the negatives. If the negative
plates showed any bulging of the active material, they should be
subjected to the pressing treatment first, using boards and a vise
as described in connection with dismantling the battery. The jars
containing the positives, as well as those containing the negatives,
should be well covered to exclude all dust.

Make a memorandum of the amount of material required to
reassemble the battery and, when ordering this, provide for extra
jars and covers, extra rubber separators, and an entire lot of wood
separators, with a sufficient excess to take care of possible breakage in
handling. Unless the old connectors were very carefully removed,
order a new set. Include a supply of new electrolyte of 1.300 specific
gravity to fill all the jars. It is always well to advise the customer
when the battery is put in storage of the material that will be neces-
sary to reassemble it and request that at least a month's notice be
given in which to procure it. To reassemble the battery, proceed as
in making a complete renewal of the elements.

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129

MISCELLANEOUS OPERATIONS

Lead Burning. Type of Outfit. In the manufacture of storage
batteries and in garages where a large number of batteries are
maintained, a hydrogen-gas apparatus is employed for this purpose.
For the electric-car owner or the garage doing a comparatively small
amount of battery repair work, the Electric Storage Battery Com-
pany has placed an arc lead-burning outfit on the market. This
is low in first cost and, with a little practice, good results can be
obtained with it. As the battery itself supplies the power neces-

Fig. 86. Arc-Welding Outfit for Burning Connections

sary, the only material required is the lead in the form of a flexible
strip or heavy wire. The complete outfit is illustrated in Fig. 86.
At one end is the clamp for making electrical connection, while at
the other is a clamp of different form having an insulated handle
and holding a quarter-inch carbon rod. The two are electrically
connected by a flexible cable. This simple outfit can be employed
in two ways, the second being preferable for the beginner, at least
until a sufficient amount of skill has been acquired to use the arc
without danger of melting the straps.

First Method of Burning. In the first method, a potential of
from 28 to 30 volts (12 to 15 cells) is required. The clamp should,
therefore, be fastened to the positive pole of the twelfth to the
fifteenth cell away from the joint to be burned, counting toward the

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130 ELECTRIC AUTOMOBILES

negative terminal of the battery. The carbon then forms the negative
terminal of the circuit. Otherwise particles of carbon will be carried
into the joint, as the carbon rod quickly disintegrates when it forms
the positive pole. The carbon should project 3 or 4 inches from the
holder. The surfaces of the parts to be burned should be scraped
clean and bright and small pieces of clean lead about i to $ inch
square provided for filling the joint. The carbon is then touched to
the strap to be burned and immediately withdrawn, forming an
electric arc which melts the lead very rapidly. By moving the carbon
back and forth the arc is made to travel over the joint as desired, the
small pieces of lead being dropped in to fill the gap as required.
Owing to the high temperature generated, the work must be carried
out very quickly, otherwise the whole strap is liable to melt and run.

As this method is difficult and requires practice to secure good
results, the beginner should try his hand on some scrap pieces of
lead before attempting to operate on a cell. Its advantages are
that, when properly carried out, it takes but a short time to do the
work, and the result is a neat and workmanlike joint. It is extremely
hard on the eyes, however, and should never be attempted without
wearing smoked or colored glasses, and even with this protection
the eyes should be directed away from the work as much as possible.

Second Method of Burning. The second method, utilizing the
hot point of the carbon rod instead of the arc", is recommended for
general practice. Scrape the parts to be joined and connect the
clamp between the third and fourth cells from the joint. With this
method it is not necessary to determine the polarity of the carbon.
The latter is simply touched to the joint and held there; on account
of the heavy flow of current it rapidly becomes red- and then white-
hot. By moving it around and always keeping it in contact with
the metal, the joint can be puddled. To supply lead to fill the joint,
an ordinary lead-burning strip can be used, simply introducing the
end into the puddle of molten lead, touching the hot carbon. The
carbon projecting out of the holder should be only an inch, or even
less, in length. After the joint has been made, it can be smoothed
off by running the carbon over it a second time.

Use of Forms to Cover Joint. In joining a strap which has been
cut in the center, it is best to make a form around the strap by means
of a piece of asbestos sheeting soaked in water and fastened around

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ELECTRIC AUTOMOBILES 131

the strap in the shape of a cup, which will prevent the lead from
running down. It will be found that sheet asbestos paper is thick
enough, but it should be fairly wet when applied. By this means a
neat joint can be easily made. The asbestos will adhere very tightly
to the metal, due to the heat, but can be removed by wetting it
again. When burning a pillar post to a strap, a form may be made
around the end of the strap in the same manner, though this is not
necessary if reasonable care is used. Two or three pieces of j^-inch

Fig. 87. Lead-Burning Outfit for Use with Illuminating Gas
Courtety of Electric Storage Battery Company, Philadelphia, Penntylvania

strap iron about one inch wide and some iron nuts about one inch
square are also of service in making the joint, the strap iron to be
used under the joints and the nuts at the side or ends to con-
fine the molten lead. Clay can also be used in place of asbestos,
wetting it to a stiff paste. As the holder is liable to become so hot
from constant use as to damage the insulation, besides making it
uncomfortable to hold, a pail of water should be handy and the
carbon dipped into it from time to time. This will not affect its

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132 ELECTRIC AUTOMOBILES

operation in any way, as the carbon becomes hot again immediately
the current passes through it.

Illuminating Gas Outfit Heretofore it has not been possible to
do good work in lead burning with illuminating gas, but a special
type of burner has recently been perfected by the Electric Storage
Battery Company which permits of the use of illuminating gas with
satisfactory results. The outfit consists of a special burning tip and
mixing valve. Sufficient ^-inch rubber hose should be provided and
the rubber should be wired firmly to the connections A and B 9 Fig. 87,
as the air is used at a comparatively high pressure. A supply of com-
pressed air is necessary, the proper pressure ranging from 5 to 10
pounds, depending upon the length of hose and the size of the parts to
be burned. When air from a compressor used for pumping tires is
utilized for this purpose, a suitable reducing valve must be introduced
in the supply line. This outfit is designed for use with ordinary
illuminating gas and cannot be employed with natural gas.

Connect the air hose to cock A and the gas hose to cock B. The
leader hose, which should not be more than five or six feet long, is
connected to the pipe C and to the burning tip D. When the air
pressure at the source is properly adjusted, close the air cock A and
turn the gas cock B on full. Light the gas at the tip and turn on the
air. If the flame blows out, the air pressure is too high and should
be reduced, preferably at the source. With the gas turned on full,
the flame will have a ragged appearance and show a waist about
\ inch from the end of the tip, the flame converging there and spread-
ing out beyond. Such a flame is not for lead burning.

Slowly turn the gas off until the outer portion at the waist
breaks and spreads with an inner tongue of flame issuing through the
outer ring. The flame will now have a greenish color and is properly-
adjusted for burning. If the gas is turned off further or if too much
air is turned on, the flame assumes a blue color gradually becoming
invisible and is then deficient in heating power. When properly
adjusted, the hottest part of the flame is just past the end of the inner
point. Do not hold the flame too close to the work when burning,
as its heating effect is greatly reduced and the flame is spread so as to
make control difficult. The burning tip is provided with an outer
sleeve and lock nut E; this sleeve is removable and can be taken off
in case any of the holes in the tip become clogged. The position of

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ELECTRIC AUTOMOBILES 133

this sleeve is adjustable, the best position varying with the pressure
of the flame, and it should be determined by experiment.

Hydrogen-Gas Outfit, Hydrogen gas gives a hotter flame and
therefore permits of more rapid work, so that where burning is done
on a large scale, it is still preferred. The essentials of such an outfit
are: first, a hydrogen generator; second, a method of producing air
pressure at approximately 2 pounds to the square inch; and third,
the usual pipe and tips for burning. If hydrogen gas is purchased in a
tank and compressed air is available, only the blow pipe, tips, and a
reducing valve on the air line are necessary. This is an expensive
method to purchase hydrogen, however, so that it is usually generated,
and a water bottle is needed between the generator and the blow pipe
to wash the gas and to prevent the flame from traveling back to the
generator.

For this purpose hydrogen gas is generated by placing zinc in a
sulphuric-acid solution. The generator usually employed for vehicle-
battery burning requires 50 pounds of zinc, 2 gallons of sulphuric
acid, and 9 gallons of water for a charge. Where no compressed-air
supply is available, an air pump and an air tank for equalizing the
pressure must be used. An outfit of this kind is shown in Fig. 88.
In preparing the generator for use, connect up as shown in this cut,
taking care that the hose from the generator is connected to the
nipple of the water bottle L. Have the water bottle one-half to
two-thirds full and immerse it in a pail of cold water up to its neck.
Replace the water in the pail whenever it becomes warm. Have stop
cock N closed. Put the required amount of zinc, which has been
broken into pieces small enough to pass through the opening C,
into lower reservoir. Put on cap A" and screw down with clamp D,
being sure that the rubber drainage stopper II is well secured in
place. Pour the proper amount of water into reservoir A and then
pour in the acid, taking care to avoid splashing. Always pour the
water in first

In running the hose from A' to A T , arrange it so that there will be
no low points for the water of condensation to collect in; in other
words, this hose should drain back at every point to the water bottle.
If, however, water should collect in the hose to such an extent as to
interfere with the flame and it cannot readily be drained off, kink the
hose between T and U and detach it from A'; close the stop cock at

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ELECTRIC AUTOMOBILES

W and pump until a strong pressure is obtained in the tank; then close
the cock at I r , opening those at S and N and, finally, quickly open W ;
the pressure in the air tank will then force the water out of the hose.
The length of the hose from T to U should be such that the mixing
cocks at S and N are always within easy reach of the man handling
the flame.

In preparing the flame for burning, close the air cock at S and
open iV wide, hold a match to the gas until it lights, then add air
and adjust the gas cock slowly, turning toward the closed position

1 1

kfeq

Fig. 88. Diagram of Lead-Burning Outfit, Using Hydrogen Gas

until the flame, when tried on a piece of lead, melts the metal and
leaves a clean surface. The tip to be used depends on the work, but
most vehicle-battery work is done with the medium tip. Replenish
the zinc every few days, keeping it up to the required amount. When
a charge is exhausted or the generator is to be laid up for the night,
the old solution should be drawn off before making up a new charge
and the generator thoroughly flushed out by running water through A.
The new charge should not be put in until the generator is to be used
again. To empty the generator, first pull off the hose at the nipple
A', then at E, and finally the rubber plug at H. Take care not to

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allow the solution to splash on anything and not to dump the gener-
ator where the contents will damage cement, asphalt, or wood walks.
Freezing. In addition to taking care that the temperature of
the cells does not exceed 100° F. on charge, precautions are also
necessary to prevent the temperature of the battery falling too low,
as a drop in temperature causes a falling off in the efficiency. This
is particularly true of the alkaline battery, the output curve of
which drops off rapidly below 60° F., so that this type of battery is
usually installed in a manner which keeps it at an even tempera-
ture, making it possible to operate it successfully in zero weather.
Furthermore, in the case of the lead cell, freezing must be guarded
against. To avoid this, the battery should always be kept fully
charged in cold weather, as a charged cell will not freeze in the
temperatures ordinarily experienced. Electrolyte will freeze at
various temperatures, according to the state of charge as follows:

Sp. Gr. 1.120 battery fully discharged 20° F. above zero

Sp. Gr. 1.160 battery three-quarters discharged Zero F.

Sp. Gr. 1.210 battery half-discharged 20° F. below zero

Sp. Gr. 1.260 battery one-quarter discharged 60° F. below zero

When a battery is stored away for the winter, care should be
taken not to let the temperature of the place in which it is kept fall
below 20° F., or else the battery should be kept fully charged.

Putting New Battery in Commission. One of the things that
the garage man caring for electric vehicles will be called upon to do
at intervals will be the ordering and installation of a new battery in a
car. As received from the manufacturer, the battery is in a charged
condition, that is, it was fully charged just previous to being shipped,
but it must be inspected and tested before being placed in the car.

Inspection of Battery. To avoid spilling the electrolyte from the
cells, care must be taken in unpacking the trays. After cleaning off
the excelsior and other packing from the tops of the cells, the soft
rubber plugs should be removed from all the latter to note if they
all contain the proper amount of electrolyte. This should be \ inch
over the tops of the plates. If the electrolyte is uniformly below the
proper level in all the cells, this is evidently due to evaporation; add
enough distilled or rain w r ater to bring the level to the proper height.
But if the level of the electrolyte is found to be low in some cells only,
this is due to loss of electrolyte. If this has resulted from the trag-
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136 ELECTRIC AUTOMOBILES

having been turned over in shipment, the excelsior around the top of
the tray will be wet (the acid does not evaporate), and some acid
would be spilled from all the cells in that tray. In this case, replace
the amount lost by filling the low cells to the proper height with chemi-
cally pure electrolyte of 1 .250 specific gravity (seven parts of water
to two pure sulphuric acid, by volume).

Replacements. If the electrolyte in a cell is low, due to a broken
jar, the bottom of the tray will be wet, though the excelsior around the
the top may be dry. Replace the broken jar as detailed in the instruc-
tions given under that heading and add sufficient electrolyte of 1.250
specific gravity to make up for that lost. Should it be found, after
replacing the broken jar and giving the battery an equalizing charge,
that the gravity does not reach approximately 1.275, it is due to
not having replaced the same amount of acid as was spilled. To
adjust this, draw off with a syringe some of the electrolyte from the
top of the cell and add water or 1.300 acid to bring the specific gravity
to between 1.270 and 1.280.

Charging. Put the battery on charge at the low rate given on the
name plate on each tray. Charge at about this rate until all the
cells gas uniformly. Reduce the current to one-half that rate and
continue the charge for three hours longer, when the battery will be
ready to put into service. It is advisable, however, before putting
the battery into service, to take and record the specific gravity of the
electrolyte of each cell and the temperature of one or more of the cells.

Packing a Battery. It is sometimes necessary to ship a battery
back to the manufacturer for repairs, and the amount of damage
occasioned in transit by improper packing has led the makers to issue
special instructions for doing this. A box at least 2 inches larger in
each direction than the overall size of the battery tray should be made
of strong 1-inch or 1^-inch planks. It should be made with an A-
shaped top to prevent placing it any other way than upright. Where
more than one tray is shipped in a box, 2 inches must be allowed
between the trays. The maximum permissible weight, however, is
200 pounds. Cover the bottom of the box with a layer of sawdust,
excelsior, or coarse shavings to a depth of 2 inches, and on this place
the tray of cells. Over the top of the cells place paraffined paper and
then cover the whole tray with stout wrapping paper, folding it down
over the sides of the tray to keep packing material and dust out of

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the cells. Fill the space around the sides with sawdust or excelsior,
or even with w r aste paper twisted into balls and wads, ramming the
whole down tightly so that the tray cannot move. Xail slats on the
box for a cover (never make a solid cover), and nail a stout strip on
each side extending beyond the ends, for handles. The slatted cover
enables the freight handlers to see the contents and makes for more
careful handling. Label the box "handle with care" and "do not
drop". Put your own name and address on the package as well as
that of the battery manufacturer, and notify the latter of the ship-
ment. Complete batteries should be shipped as "electric storage
batteries assembled". No railroad caution labels are required as the
electrolyte in the cells is so dilute that acid in this form is exempted
from the rules applying to its shipment in other forms. Boxes of good
elements, or plates, should be shipped as "Lead Battery Plates",
while worn-out plates may be shipped as "Scrap Lead", boxes of jars
as "Rubber Battery Jars", covers and separators as "Rubber Goods",
and empty trays as "Empty Wood Crates". By properly designating
the material as above in the bill of lading, the most favorable freight
rate may be obtained.

Causes of Low Battery Power. A decrease in the speed or mileage

of a car does not necessarily mean a lack of capacity in the battery.

If the current consumption is greater than normal, it may be due to

trouble with the transmission, motor, or running gear — the car

"runs hard" — or it may be due to poor connections. When other

causes fail, then it is probably the battery, and its lack of capacity

may always be traced to some definite cause. There may be a dry

cell, due to a leaky jar; some or all of the cells may be in a state of

incomplete charge, due to the battery having been run too low and

not sufficiently charged. The plates may be short-circuited by

excessive deposit of sediment, or by something falling into the jar.

If the trouble cannot be located upon examination, connect the

battery in series and discharge it at the normal rate through a suitable

resistance, as already explained. As the discharge progresses the

voltage will gradually decrease, and it should be frequently read at

the battery terminals. As soon as it shows a sudden drop, the voltage

of each cell should be taken with a low-reading voltmeter. While

the readings are being taken, the discharge rate should be maintained

constant, and the discharge continued until the majority of the cells

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138 ELECTRIC AUTOMOBILES

read 1.70 volts. Those reading less than this should be noted. The
discharge should then be followed by a charge until the cells which
show 1.70 volts are up. Then the low cells should be cut out and
examined and the trouble remedied. Assuming that there are no
short-circuits, low specific gravity of the electrolyte in such a cell
will indicate sloppage or a leak, the loss from which has been replen-
ished with water alone. Or it will be a sign of insufficient charge,
over-discharge, standing in a discharged condition, or a combination
of these abuses. Any one of these indicates that there is acid in
combination with the active material of the plates, and it should be
brought out by a long charge at one-quarter the normal discharge
rate. Continue charging until the specific gravity of the electrolyte
stops rising; then adjust to normal (1.270 to 1.280) by drawing off
some of the electrolyte and adding water if it be above normal, and
by adding acid if it be below normal. The low cells should be
grouped by themselves and charged as a separate battery.

STANDARD INSTRUCTIONS FOR STORAGE BATTERIES
As Issued by the Society of Automobile Engineers

1. Batteries must be properly installed.

Keep battery securely fastened in place.

Battery must be accessible to facilitate regular adding of water to, and
occasional testing of, solution. Battery compartment must be ventilated and
drained, must keep out water, oil, and dirt and must not afford opportunity for
anything to be laid on top of battery. Battery should have free air space on all
sides, should rest on cleats rather than on a solid bottom and holding devices
should grip case or case handles. A cover, cleat, or bar pressing down on the
cells or terminals must not be used.

2. Keep battery and interior of battery compartment wiped clean
and dry.

Do not permit an open flame near the battery.

Keep all small articles, especially of metal, out of, and away from, the bat-
tery. Keep terminals and connections coated with vaseline or grease. If
solution has slopped or spilled, wipe off with waste wet with ammonia water.

3. Pure water must be added to all cells regularly and at suffi-
ciently frequent intervals to keep the solution at the proper height.

The proper height for the solution is usually given on the instruction' or name-
plate on the battery. In ail cases the solution must cover the battery plates.

The frequency with which water must be added depends largely upon the
battery, the system with which it is used, and the condition of operation. Once
every two weeks is recommended as good practice in cool weather; once every
week in hot weather.

Plugs must be removed to add water; then replaced and screwed home after
filling.

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Do not use acid or electrolyte, only pure water.

Do not use any water known to contain even small quantities of salts of any
kind. Distilled water, melted artificial ice, or fresh rain water arc recommended.

Use only a clean non-metallic vessel.

Add water regularly, although the battery may seem to work all right
without it.

4. The best way to ascertain the condition of the battery is to
test the specific gravity (density) of the solution in each cell with a
hydrometer.

This should be done regularly.

A convenient time is when adding water, bid the reading should be token before,
rather than after, adding the water.

A reliable specific gravity test cannot be made after adding water and before it
has been mixed by charging the battery or by running the car.

To take a reading, insert the end of the rubber tube in the cell. Squeeze
and then slowly release the rubber bulb, drawing up electrolyte from the cell
until the hydrometer floats. The reading on the graduated stem of the hydrome-
ter at the point where it emerges from the solution is the specific gravity of
the electrolyte. After testing, the electrolyte must always be returned to the cell
from which it was drawn.

The gravity reading is expressed in "points", thus the difference between
1250 and 1275 is 25 points.

5. When all cells are in good order the gravity will test about the
same (within 25 points) in all.

Gravity above 1200 indicates battery more than half charged.

Gravity below 1200 but above 1150 indicates battery less than half charged.

When battery is found to be half discharged, use lamps sparingly until, by
charging the battery, the gravity is restored to at least 1200. See Section 8.

Gravity below 1150 indicates battery completely discharged or "run down" .

A run-down battery should be given a full charge at once. See Sections
7 and 8.

A run-down battery is always the result of lack of charge or waste of cur-
rent. If, after having been fully charged, the battery soon runs down again,
there is trouble somewhere else in the system, which should be located and
corrected.

Putting acid or electrolyte into the cells to bring up specific gravity can do
no good and may do great harm. Acid or electrolyte should never be put into
the battery except by an experienced battery man.

6. Gravity in one cell markedly lower than in the others, especially
if successive readings show the difference to be increasing, indicates that
the cell is not in good order.

// the cell also regularly requires more water than the others, a leaky far is
indicated.

Even a slow leak will rob a cell of all its electrolyte in time, and a leaky jar
should be immediately replaced with a good one.

// there is no leak and if the gravity is, or becomes, 50 to 75 points below that
in the other cells, a partial short-circuit or other trouble within the cell is indicated.

A partial short-circuit may, if neglected, seriously injure the battery and
should receive the prompt attention of a good battery repair man.

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7. A battery charge is complete when, with charging current flow-
ing at the rate given on the instruction-plate on the battery, all cells
are gassing (bubbling) freely and evenly and the gravity of all cells has
shown no further rise during one hour.

The gravity of the solution in cells fully charged as above is 1,275 to 1,300.

8. The best results in both starting and in lighting service will be
obtained when the system is so designed and adjusted that the battery
is normally kept well charged, but without excessive overcharging.

//, for any reason, an extra charge to maximum specific gravity is needed, it
may be accomplished by running the engine idle, or by using direct current from an
outside source.

In charging from an outside source use direct current only. Limit the
current to the proper rate in amperes by connecting a suitable resistance in series
with the battery. Incandescent lamps are convenient for this purpose.

Connect the positive battery terminal (painted red, or marked POS or
P or +) to the positive charging wire and negative to negative. If reversed,
serious injury may result. Test charging wires for positive and negative with a
voltmeter or by dipping the ends in a glass of water containing a few drops of
electrolyte, when bubbles will form on the negative wire.

9. A battery which is to stand idle should first be fully charged.
See Sections 7 and 8.

A battery not in active service may be kept in condition for use by giving it a
freshening charge at least once every two months, but should preferably also be given
a thorough charge, after an idle period, before it is replaced in service.

A battery which has stood idle for more than two months should be charged at
one-half normal rate to maximum gravity before being replaced in service.

It is not wnse to permit a battery to stand for more than six months without
charging.

Disconnect the leads from a battery that is not in service so that it may not
lose through any slight leak in car wiring.

SOME SOURCES OF POWER LOSS

As the power of the electric vehicle is closely limited by the
capacity of the battery it carries, it is absolutely essential that every
part of the mechanism be kept in good running order so that none
of the power may be wasted. Whether the machine is considered
as a w r hole, or each component is treated separately, the electric
vehicle is about as simple as it possibly could be. But the number
of places at which power losses may occur will greatly surprise the
uninitiated owner when he comes to look into the subject. It is
nothing unusual for the purchaser of an electric vehicle to write the
maker a year or so after he has bought it that while the car ran per-
fectly satisfactorily at first, its mileage has now been very much
reduced. He has followed instructions implicitly, the battery has been
well looked after, and, according to all indications, it is in as good

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condition as ever it was, but it is impossible to obtain anything like
the rated mileage from a full charge of the battery. A little investi-
gation will show that, in the majority of cases, the owner, who has
not had the advantage of a mechanical training, has become so
impressed with the great importance of properly maintaining the
electrical end of the car that he has disregarded its mechanical
efficiency entirely.

Non-Alignment of Steering Wheels. One of the most prolific
sources of power losses, and one of the last to be suspected, is non-
alignment of the wheels. A chance blow in drawing up along-
side a curb is sometimes sufficient to make one of the front wheels
"toe in" slightly. The fault is not noticed and may be aggravated
by subsequent blows at the same spot, or on the other wheel. This
may cause the bearings to bind to a certain degree and also to impose
a heavy load on the motor by the new angle which the tires make
with the road surface. It is difficult for the average layman to
appreciate how great an increase in the load such a seemingly trivial
fault as this may create, and it can only be realized to a certainty by
keeping a record of the ammeter readings at all of the speeds under
normal conditions. Just how much current is required to start and
to mount various grades should be noted. As the service of an
electric vehicle is chiefly confined to urban travel and covers prac-
tically the same routes day after day, it is possible to keep a close
check on current consumption by noting how far the ammeter
needle travels over the dial in running on the level and in mounting
grades that have to be climbed frequently. Small increases in the
current required to do the same work at different times would then
be readily apparent, and as the malady is imposing an extra drain
on the battery, which is simply a waste of energy, its cause should
be looked for and remedied.

The electric vehicle is a power-measuring machine without an
equal, and' the driver who has familiarized himself with the per-
formance of his car under favorable conditions should be able readily
to detect the presence of trouble by the increased current consump-
tion and the correspondingly decreased mileage per charge. The
causes may be electrical as well as mechanical, and w r here a car has
not been properly looked after, it is more than likely that the falling
off in the available radius on a single charge will be traceable to an

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accumulation of causes small in themselves, but of considerable
importance in the aggregate. Disalignment of the front wheels
may sometimes be due to the steering gear — that is, the connecting
rod which serves to keep these wheels parallel — working out of
adjustment. Unless they are perfectly aligned, they not only make
more current necessary to propel the vehicle, but they also serve to
wear out the front tires more rapidly than would otherwise be the
case. Sagging of the rear axle, which was not an uncommon fault
in earlier years, but which is now rare, will produce similar conditions
at the rear wheels and, as the entire power of the car is utilized at
this point, the result is just that much worse.

Worn Chains and Sprockets. Next in the order of importance
to badly aligned driving or steering wheels from a mechanical point
of view, comes a worn driving chain. This naturally applies to the
chains employed for either of the reductions in motor speed. It is
likewise equally true of the sprockets, but a worn sprocket is prac-
tically always the result of the continued use of an old chain. The
latter is allowed to wear to a point where its pitch is greater than that
of the teeth of the sprocket, and, in consequence, the chain shows a
constant tendency to ride the teeth of the sprocket instead of fitting
snugly between them, as should be the case. This tightens the chain
and imposes a greatly added load upon it and the sprocket, with the
result that the teeth of the latter are also soon worn out of pitch.
When this occurs, the only remedy lies in the replacement of both
chains and sprockets, as the fitting of a new chain on a worn sprocket
aggravates the evil and causes the new chain to wear to a point of
uselessness in a very short time. The best preventive is to watch
the driving chains for such conditions and to replace a chain as soon
as it gives any indication of mounting the teeth instead of running
smoothly.

These instructions apply only to pleasure models antedating
1913-14, as practically all models are now made with the shaft drive
using a bevel gear or worm; but there are thousands of the older
chain-driven cars in service, the electric having a much longer
effective life than the gasoline car.

Non-Alignment of Axles. On all electric cars, whether chain- or
shaft-driven — the former being greatly in the majority, of course —
means are provided for aligning the rear axle. These take the form

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of distance or radius rods, attached through the medium of a hinge
joint to the axle and some form of pivot joint at the countershaft, this
construction having been referred to in connection with the descrip-
tion of the tFansmission of a double chain-driven car. Although
effective means of locking these rods are provided, they are sub-
jected to constant vibration and jolting and sooner or later will
require attention. It will be apparent that if one is adjusted so as
to be somewhat shorter than the other, an excessive fraction of the
load will be imposed on the driving chain on the short side. This
will also place a very heavy strain on the differential or balance gear,
and a greatly added amount of power will be required to drive the
car. The importance of accurately adjusting the distance rods so
that the rear axle will be at right angles with the frame and of main-
taining it in that condition may accordingly be appreciated.

Dry Bearings. It would appear almost superfluous to mention
lack of oil as a mechanical source of power loss, but many electric
vehicle owners seldom attach sufficient importance to the necessity
for oiling the moving parts. It is a popular fallacy, quite generally
indulged in, that the anti-friction bearing is a mechanical device that
requires no lubrication. Ball bearings do call for less attention
in this direction than any other. They need very little oil, and at
much longer intervals than a plain bearing, but they cannot render
efficient service without some lubricant. In fact, it is this very abil-
ity to stand an uncommon amount of abuse that seems to have earned
for the ball bearing its popular reputation for ability to run quite as
well whether it is dry or oiled. The lubricant not only serves the
same end that it does in any bearing — that of reducing friction, but
it also acts as a preventive of rust — the greatest enemy of the ball
bearing; and as these bearings are very expensive replacements, it
pays to avoid this by regular oiling at least once a month. Only the
best grade of light machine oil should be employed, or a thin-bodied
and highly-refined vaseline with which the bearing may be packed.
It is quite essential that the lubricant should be entirely free from
acid, which would attack the highly polished surfaces of the balls
and races and destroy the efficiency of the bearing. The electric-
vehicle user's chief safeguard against this is to confine his purchases
to brands recommended by the manufacturer of the car. Where
the presence of acid is suspected, a simple test may be made by

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dipping a small piece of cotton waste in the lubricant and then
wrapping it around a piece of polished steel. This should be plactd
in the sun and examined at the end of a Keek or more. If the lub-
ricant contains acid, there will be traces of its etching effect on the
polished surfaces and it is useless. Oil that is entirely free from acid
will not affect the most highly polished surface.

Wheels and axles out of alignment, worn chains and sprockets,
improperly adjusted brakes, which may be dragging, and neglected
bearings sum up the chief mechanical sources of power loss.

It is quite as important, however, that losses of electric power
be guarded against, as they interfere with the efficient utilization of
the energy stored in the batteries and decrease the available mileage
on a charge, regardless of the condition of the mechanism. Vibra-
tion will prove the undoing of almost anything in the course of time,
and, w r hile every precaution is taken by the manufacturer to provide
durable and permanent connections, it seems practically impos-
sible to provide a form of terminal that will be absolutely proof
against this influence and still permit of being disconnected con-
veniently when required. Air interposes a very high resistance
in a circuit, and but a slight amount of looseness in a connection
creates an air gap that must be bridged by the current in order to
complete the circuit. This causes arcing, or a flashing of the current
across the gap, which is destructive of the terminals and is not in-
frequently responsible for the ignition of adjacent material. As will
be apparent from the wiring diagram given, there are quite a number
of such connections, and going over them systematically at regular in-
tervals is the only way to guard against current losses from this source.

Brushes and Commutator. The brushes and commutator are
the only parts of the electric motor that are subject to wear, and
the life of the commutator is naturally equivalent to that of several
sets of brushes, so that the latter constitute practically the sole item
to be looked after in connection w r ith the motor. They are either
plain blocks of carbon, or carbon with fine copper wire embedded
in it, and are held against the commutator by springs. To examine
their condition closely., the housing should be removed, the rear axle
jacked up, and the motor run on the first speed. No attempt should
be made to run it on any of the other speeds when in this condition,
nor should it be run any longer than necessary. This 4oes not

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exactly simulate actual driving conditions as, with the wheels off
the ground, practically no load is imposed on the motor and, while
the latter may spark badly under load, it will frequently give little
indication of this form of trouble when running light.

If the brushes have been sparking badly in actual service there
will be certain signs of this in the shape of the blackened commutator
bars. They should be wiped clean and, if any oil has leaked on to
them from the bearing, all traces of it should be removed. If this
does not suffice to remove the blackened appearance, the sparking
has been such as to burn the copper, and this blackened surface
should be removed with the aid of a piece of very fine sandpaper
held against the commutator while it is turning slowly. Never use
emery cloth for this purpose, as the abrasive material employed in
its manufacture is of a metallic nature, and not only tends to embed
itself in the insulation between the bars, but, once there, serves as a
conductor and may short-circuit some of the armature coils, result-
ing in serious damage to the motor. If the brushes merely appear
to be glazed but still make good contact all over the bearing surface,
the latter may be rubbed with the sandpaper as well. If they have
worn to a point where the contact is not good, new brushes should
be substituted, and it would be well for the owner of the electric
vehicle who is not familiar with the motor, to have an experienced
person put them in for him the first time — every time, in fact, unless
he is perfectly sure of his own ability in this line. A set of brushes
will seldom, if ever, need replacement more than once during an
entire season.

For instructions covering seating of brushes, testing springs,
and the like, refer to sections on these faults in the article on
Starting Motors and Lighting Generators.

Armature Troubles. When the housing is off, the brush con-
nections and other motor connections should be inspected for loose-
ness or other faults. Instructions for locating grounds, short-
circuits, or open circuits in the armature and field windings are
given in connection with the articles on Starting and Lighting
Systems.

The armature is supported on annular ball bearings in the major-
ity of cases, and while these bearings require periodical oiling as much
as the remaining ones of their kind on the car f pains must be taken

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146 ELECTRIC AUTOMOBILES

to use the oil sparingly in order to prevent it reaching the commu-
tator at one end or the armature windings at the other.

Miscellaneous. In speaking of connections, those at the battery
are included and they should be inspected as well. The connections
between the different cells are usually made by burning the lead-
strap terminals together, though some have bolted connections, and
these may jar loose; but the various groups are connected to one
another and to the remaining apparatus, and these terminals are
probably more apt to give trouble than some of the others, as it is
nothing unusual to remove the battery at times and sufficient care
is not always exercised to have the connections solidly fast.

The loss of electrical energy, due to undercharged and short-
circuited cells in the battery, has been treated in detail in connection
with the care of the battery.

Tires are, without doubt, one of the greatest sources of power
loss on the electric vehicle, and it is one that mystifies the uninitiated
exceedingly. This matter is gone into at length in connection with
tire equipment.

TIRES AND MILEAGE

Relation of Tires to Mileage. It will appear odd and some-
what inexplicable at first sight that these two headings should be
included in the same chapter, for the average man thinks that the
only thing which has any direct influence on the mileage of the car
is the amount of energy the battery is capable of giving forth. As
is pointed out under "Sources of Power Loss", there are many other
factors that affect the available radius of the car more or less indi-
rectly. Tires are not included among these indirect sources, as the tire
equipment has a most direct and, therefore, a most important bearing
on the distance the electric car is capable of traveling on a single
charge of the battery. The gasoline machine is endowed with such
a liberal surplus of driving power that the loss occasioned by tires
represents but an insignificant fraction of the whole; in other words,
is a totally negligible factor. Had it not been for extensive experi-
ments carried out in connection with the electric automobile, the
importance of these losses would not have been definitely known.

When all the points which contribute to both the electrical and
mechanical efficiency of the car have been carefully maintained in

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proper working order, and still both the speed and total capacity
of the battery fail to respond, the cause of the trouble may be summed
up in a single word — "tires". For tires constitute the most impor-
tant element in the determination of mileage and, though that fact
is seldom, if ever, mentioned in connection with accounts of phenome-
nal mileages made on a single charge, they are the chief controlling
factor. The tires usually employed for such "stunts" are specially
made for the purpose and are not adapted to ordinary service. They
have extremely thin walls, with the thread of the fabric reinforcement
running continuously round the tread of the tire in the same direc-
tion, and are not only very likely to puncture on slight provocation,
but are far from durable. The expense of employing such tires
regularly would be prohibitive, particularly as they are very difficult
to repair when punctured.

Kinds of Tires. Pneumatic. For the usual pleasure-car service,
electric-vehicle manufacturers fit tires that experience has shown
not alone to be best adapted to the peculiar needs of this type of
automobile, but likewise sufficiently durable for the purpose. Pneu-
matic tires are a luxury and will always be a source of considerable
expense, so that tire life is a factor to be taken quite as much into
consideration as battery mileage. On the gasoline car, in view of
the great weights and high speeds, it is solely a question of being
able to make the pneumatic tire sufficiently strong to stand the
unusually severe stresses to which it is subjected. To accomplish
this end, the fabric structure forming the foundation of the shoe, or
outer envelope of the tire, is made of various layers of heavy canvas
placed at angles to one another and solidly vulcanized together.
This construction makes an extremely stiff wall, as is evidenced by the
difficulty in forcing"a clincher type of tire on to the rim. Such a tire
will yield to the minimum degree under the weight of the car or road
obstacles when inflated to the proper pressure. In consequence, it
absorbs an enormous amount of power. This loss is still further
increased by the use of chains, studs, or similar anti-skid devices.
Tests made on the recording dynamometer of the Automobile Club
of America in New York City have shown that some forms of non-
skid treads, particularly those employing heavy steel studs embedded
in thick leather, absorbed as much as 5 horsepower per wheel to
drive them. Tests showing 2 to 2 \ horsepower per wheel were not

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148 ELECTRIC AUTOMOBILES

uncommon, and in but few instances did the loss drop below 1 horse-
power per driving wheel, regardless of the type of tire employed.

It would be manifestly out of the question to expect much in
the way of mileage from an electric vehicle if handicapped in this
manner. Non-skid devices of any kind are rarely seen on electric
automobiles for this reason, about the only occasion when they are
in evidence being in winter, when they are actually required on ice
or slushy pavements to afford sufficient traction. For electric
service a structure is required in which the fabric foundation is so
constituted as to be able to adapt itself most readily to the distortion
caused by being pressed out flat on its contact area w T ith the road.
A tire constructed wholly of rubber, such as an inner tube, would be
ideal, but wholly impracticable. The conditions to be met represent
but another instance of the conflicting requirements found on every
hand in automobile design. In other words, it is axiomatic that the
ease with which a tire punctures is in direct proportion to the ease
with which it runs.

Next to a pure rubber tire comes one in which threads or cords
are individually embedded in the rubber. It will be apparent that
such a tire is far more frail than those in which stiff canvas is
employed as a foundation, and that the individual threads do not
present any effective resistance to puncture. To be efficient from
the point of service, it has been found essential to make a tire in two
parts, i. e., a tube of pure rubber as an air container, and a shoe or
outer protective cover to take the strain. Experiments with the
single-tube tire or "hose-pipe" type, — that is, one in which the air
container and the shoe are one — demonstrated that it was utterly
unfitted for gasoline-car w r ork. But the addition of the tube is
another item that serves to cut dowTi the power of an electric car.

Solid. Viewed from one aspect, the electric has an advantage
over the gasoline car. Owing to its greatly reduced speed, the
owner of an electric finds the solid-rubber tire a practical option.
Naturally, there can be no comparison between the riding qualities
of a solid and a pneumatic tire, b t as most electric-vehicle work is
over smoothly paved streets, and the reasonable driver should never
take obstructions except at a greatly reduced speed, the solid tire
provides an amount of comfort out of proportion to its greatly
reduced cost as compared with the pneumatic. The mileage radius

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ELECTRIC AUTOMOBILES 149

possible with a good solid tire is about the same as that possible with
the standard fabric type of pneumatic usually referred to by the
electric-vehicle manufacturer as a "gasoline" type of tire, with the
advantage in favor of the former in that it is free from puncture.

Test Curves. An extensive investigation has been made of the
subject of tires in the past few years and considerable data compiled.
Herewith is given a series of curves prepared by the builders of the
Itauch and Lang electrics which will suffice to reveal the great dif-
ferences in tires where the question of mileage is concerned, Fig. 89.
The curves show that of the solid types experimented with the

Fig. 89. Curves Showing Tests of Various Tires Made by Ranch and Lang Carriage Company

Motz tire rendered the best performance. On referring to the chart,
it will be apparent that the showing of the tire in question is some-
what more uniform than the Diamond pneumatic type. At the
high limit of the range is to be found the Palmer cord tire, which
is a single-tube type of pneumatic with thread fabric. Bearing in
mind the fact that increasing speed means a corresponding reduction
in the mileage, the application of the chart is simple. Taking the
Palmer tire just referred to as an example, select in the vertical
column at the left marked "miles per hour", the rate at which the
car is to travel. Trace this along the horizontal line representing
the speed, to the right, until it intersects the characteristic curve of
the tire in question. At that point, rise perpendicularly to the point

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where the vertical line meets the top of the chart, which is divided
into sections giving total mileage, by increments of 10 miles. For
instance, suppose it be desired to run a car at 15 miles an hour on
Palmer cord tires. Tracing the 15-mile line to the right, it will be
found to intersect the Palmer-tire curve at the vertical line corre-
sponding to 100 miles. A striking example of the manner in which
mileage increases with reduced speed may be seen by tracing the
125-mile line to the right until it intersects the Palmer curve. It
gives a total mileage of 123, or an increase of 23 per cent in the
distance covered for a decrease of but 2\ miles per hour in the speed.
By making a further reduction to 10 miles an hour, 130 miles could
be covered on a charge. This, of course, is not due to any charac-
teristic of the tire, but to the fact that the lower the discharge rate
the greater the capacity of the battery, the phenomenal mileages
given being the result of employing a tire that presents the minimum
of resistance to bending.

Such a tire, however, is not only high as to initial cost but it is
also most susceptible to puncture and difficult of repair, and for these
reasons is not available for the average user of an electric. The
expense would be practically prohibitive. The chart shows the
Morgan and Wright thread-fabric Dunlop to be capable of a very
excellent speed and mileage performance, and for those who are
desirous of combining these qualities in an electric, even at an
increased cost for tire equipment, the vehicle makers recommend
it. Its liability to puncture is less, and it will give reasonably
good service, commensurate, of course, with the care given it. The
solid tire at a 10-mile-an-hour speed is seen to be superior to the
gasoline type of pneumatic, the latter falling below it in point of
total distance by fully 12 miles.

New Tire Equipment. A little study of the foregoing will serve
to reveal one of the most prolific causes of complaint on the part of
uninitiated owners of electric vehicles. After wearing out one or two
tires in service, they instruct the garagemen to put "new ones" in
their place, or they renew the old ones by purchasing in the open
market themselves. Unless informed as to the purpose for which
the tires are needed, both the garagemen and the tire salesman are
more than apt to supply a gasoline type of tire. A distinct falling
off in the mileage radius of the car is at once noticeable, particularly

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if the owner has been in the habit of making use of the
higher speeds. The cause is apparently inexplicable, and the result
is a complaint to the manufacturer that something has gone wrong
or that the car is not fulfilling the promises made for it, when, as a
matter of fact, greater care should have been taken to maintain the
tire equipment the same throughout. "A chain is as strong as its
weakest link/' and an electric is only as fast as its slowest tire.
Every electric driver should learn the name of the tire which the
manufacturer has tested out and proved to give satisfaction and stick
to this make. Something "just as good" will not do.

Improper Inflation. Tires have been previously mentioned as
one of the sources of power loss, and the foregoing serves to explain
to a great degree why this is so. An item of considerable importance
in the treatment of tires, which has not been referred to, is improper
inflation. A soft tire naturally consumes more power to drive it
because of the increased friction due to the greater area of the tire
in contact with the ground. Such a condition is detrimental to the
tire itself as it increases the amount of wear and the danger of rim
cuts. As a means of guarding against this, air-pressure gages are
most frequently recommended, but their use merely affords an arbi-
trary standard of pressure that it is not always adaptable to the condi-
tions. As an ideal condition, a tire should only be pumped sufficiently
hard to properly carry the load imposed upon it, and with a little
practice one can readily determine by the eye whether this point
has been reached.

If the tire be too soft, the weight of the car will cause it to spread
unduly at the point of contact with the road and this condition will be
immediately noticeable. On the other hand, when the tire is pumped
up too hard, the tire will stand just as if it were bearing no load. Such
a condition obviously places too great a strain on both the fabric and
the rubber, and is frequently the cause of tire failures that are usually
assigned to a totally different reason. With its ordinary load of pas-
sengers, the electric should only cause a slight flattening of the tires
at the tread, experiment showing that the best results are obtained
when the increase in the width of the tire is about 20 to 25 per cent,
that is, a 3-inch tire when properly inflated should measure approxi-
mately 3f inches across its horizontal diameter at the part in contact
with the road.

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Fig. 90. General Electric Volt-Ammeter

Fig. 91. Volt- Ammeter with Cushion Base

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ELECTRIC INDICATING INSTRUMENTS AND THEIR USES
Volt-Ammeter. With an electric, it is important to watch the
volt-ammeter. An example of this type of combined instrument is
shown by the accompanying illustration, Fig. 90. It will be noted
that the indicating needle of the ammeter does not go to the end of
its scale, but reads both ways, the scale to the left hand being for
the charging current, and that to the right for the discharging cur-
rent. These instruments are manufactured in various forms, one
type very much in use having the voltmeter and ammeter scales
parallel in a vertical plane. Some also have the voltmeter scale so
divided that the reading of the individual cells may be taken. To
be accurate, the armature of such instruments must be very care-
fully adjusted on jeweled bearings almost as delicate as those of a
watch, and as the vibration and jolting of the vehicle are naturally
detrimental to the maintenance of its accuracy, volt-ammeters are
now being built with a cushion base, as shown in Fig. 91.

By becoming familiar with the readings of the instrument and
by realizing their significance, the driver of an electric automobile
"is in a position not only to judge whether the battery is giving the
proper service, but he also has an accurate gage on the con-
dition of the running gear and transmission of the vehicle itself.
The instrument is capable, therefore, of giving ample warning
by its deflections of any weakness, whether electrical or me-
chanical.

Ampere-Hour Meter. While the volt-ammeter affords a con-
stant indication of the working of the battery, as well as the efficiency
of the transmission, and is accordingly indispensable, it does not
permit of the direct reading of the state of charge nor indicate off-
hand how much of the energy has been utilized and how much
remains available at any given time. For this purpose the Sangamo
ampere-hour meter has been developed and generally adopted by
the builders of both pleasure and commercial electric cars. Fara-
day's law shows a definite relation between the mass of material
transferred from the plates to the electrolyte of a storage cell and
the ampere hours. That is, if the number of ampere hours absorbed
by the battery is known, there is a direct measure of its state of
charge, and consequently an ampere-hour meter may be used as a
charge indicator.

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ELECTRIC AUTOMOBILES

Method of Use. To keep the battery plates in good working con-
dition, it is necessary to give the battery a certain amount of charge,
so that under normal conditions more ampere hours must be put into
the battery than can be taken out of it. (See Fig. 11, Part 1, page
27.) This difference is the overcharge, and it must be taken into
account in figuring the number of ampere hours in a battery avail-
able for useful work. Since the only information desired by the
driver is how much energy can be taken from the battery, the San-
gamo ampere-hour meter is designed to compensate for the over-
charge, and indicates at all
times the current available
without the necessity of re-
setting the pointer every time
the battery is charged. This
is accomplished by means of
a differential shunt, as shown
by the diagram, Fig. 92.
Two shunts are employed,
and the relative value of
their resistance is adjustable
by means of the sliding con-
nection G, so that the meter
can be made to run slow on
charge or fast on discharge,
as desired. The usual method

Fig. 92. Circuit Diagram of Differential Shunt is to allow the meter to
Type Sangamo Ampere-Hour Meter .111

register less than the true
amount on charge and the exact amount on discharge, the difference
representing the loss in the battery, or overcharge. Thus the bat-
tery and the meter will keep in step for considerable periods with-
out readjustment.

Readjusting the Meter. However, over long periods of use
under varying conditions, the battery losses will vary and in time
the meter and battery will get out of step. Therefore, it is good
practice to give the battery an extra overcharge at stated intervals
and reset the meter, a simple device being provided for this purpose.
Moreover, in vehicle work the batteries are frequently subjected to
excessively high discharge rates and, under such conditions, the

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ELECTRIC AUTOMOBILES

155

battery suffers an actual loss of capacity, which requires further
compensation, as otherwise the meter will give a false indication of

Fig. 03. Variation of Useful Ampere-Hour Capacity of Lead Battery with Discharge Rate

the number of ampere hours available. The variation in the capacity

of the battery with its discharge rate is shown by the curves, Fig. 99.

To make clear the method of compensating for this loss, a brief

description of the meter itself is given.

Description of Construction Features. This meter is known as

the "mercury-flotation" type, and consists essentially of a copper disk

floated in mercury between the
poles of a magnet, and provided

CUKfCNT

Fig. 94. Electric and Magnetic Circuits of
Sangamo Ampere-Hour Meters

Fig. 9& Relative Directions of Currents,

Magnetic Flux and Motion of Disk,

Sangamo Meters

with connections to and from the mercury at opposite points. The
theoretical relations of the various parts are shown in the sketch,
Fig. 94. The current enters the contact C, passes through the

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156 ELECTRIC AUTOMOBILES

comparatively high-resistance mercury H to the edge of the low-
resistance copper disk D, across through the disk to the mercury H
and out at the contact C%. The magnetic flux cuts across the disk
on each side from N to S, making a complete circuit through if i,
and 3/2. The relative directions of the magnetic flux and the cur-
rent, as well as the resulting motion, are shown diagrammatically by
Fig. 95. According to the laws of electromagnetic induction, if a
current-carrying conductor cuts a magnetic field at right angles, a

Fig. 96. Section of Sangamo Mercury Motor Ampere-Hour Meter with Magnets
and Recording Mechanism Removed

force is exerted on the conductor, tending to push it at right angles
to both the current and the magnetic flux. When connected to an
eddy-current damper or generator which requires a driving force
directly proportional to the speed of rotation, the mercury motor-
generator becomes a meter. The speed of such a meter is a measure
of the current or rate of flow through the motor element, and each
motor revolution corresponds to a given quantity of electricity.
Then by connecting a revolution counter to this motor-gener-
ator, a means is provided of recording the total amount of electricity
in ampere hours that is passed through the meter. The method of

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ELECTRIC AUTOMOBILES 157

applying these principles in the construction of the Sangamo ampere-
hour meter is shown by the sectional view, Fig. 96, in which the
damping magnets and recording mechanism have been removed,
though the upper part of the motor magnet, which is a laminated
iron ring embedded in molded insulation — just above the copper
disk — is shown plainly. In addition to making the bearing pressure
independent of the weight of the moving elements, the armature
disk being also immersed in mercury acts as a buffer and prevents
injury to the bearings from shock.

The compensator for loss of battery capacity consists of an
electromagnet shunted magnetically across the poles of the motor
field magnet, its winding being in series with the discharge circuit.

fig. 07. Ampere-Hour Meter Compensation for Discharge Ratea Above Normal

Current through the exciting winding increases the magnetic flux
through the motor element, thus speeding up the meter with an
increase in current according to a definite and predetermined char-
acteristic. Therefore, under very high discharge rates, the meter
will register not only the ampere hours used but also those lost
through excessive current or high discharge rate. The discharge
curve characteristic, of such a meter is shown in Fig. 97.

In the Edison battery, the transfer of active material does not
take place between the electrolyte and the plates, but from one
plate to the other, as in the ordinary electrolytic cell, commonly
known as a primary battery. Therefore, the specific gravity of the
electrolyte does not change with the state of charge and, conse-
quently, the only direct way to measure the state of charge is with an

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158

ampere-hc
of capacit;

alkaline c
does not i

the drop i
such that,
same as w

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ELECTRIC AUTOMOBILES 159

Types of Instruments. The most widely used type of ampere-
hour meter for electric vehicle service is equipped with a simple
circular dial, as shown by Fig. 98, the dial being calibrated to read
to any desired number of ampere hours per revolution. It is custom-
ary to have one revolution of the pointer represent the total avail-
able energy of the battery. Where it is desired to keep a record of
the total amount of electricity either used or furnished by a battery
in order to keep a check on operating economy, totalizing dials, such

Fig. 100. Sangamo Ampere-Hour Meter and Weston Ammeter in Same Case

as are used on the ordinary watt-hour meter in residence and power
service, are fitted in addition. In cases where it is desired to keep
a record of both charge and discharge ampere hours, two sets or
duplex recording dials are fitted. With such a meter the cost of
energy input in kilowatt hours is reckoned from the charge dials,
while the ampere-hour output is read directly from the discharge
dials.

On pleasure cars, where the presence of a large meter on the
dash is not desirable for appearance's sake, an extension-dial type

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of meter is employed, only the small dial face, Fig. 99, appearing.
This illustration shows the direct reading pointer and the totalizing
dials described above. These meters may also be fitted with the
zero contact or automatic charge-stopping device, as mentioned in
the article on "Charging"; but in this case the usual resetting device
is not incorporated, the hand being reset simply by removing the cup
and turning it with the finger against the pull of the friction drive
to any desired position, where, upon release, it will be picked up
again by the driving mechanism.

But in order to bring the operation of the battery under the
strictest conditions of economy the single ampere-hour meter is not
sufficient, a combination instrument being employed. This consists of
a new type of Weston ammeter mounted in the same case as the distant
dial of a Sangamo ampere-hour meter, Fig. 100. The latter shows
the state of charge of the battery, while the ammeter indicates the
instantaneous current value or the rate of flow into or out of the
battery. A small hooded light is arranged on the dash of the
machine over the instruments to illuminate the dials at night.

SUMMARY OF ELECTRIC VEHICLE INSTRUCTIONS

While the material comprising the article in Electric Automobiles
is complete in itself, a series of brief questions clearly answered often
forms a most valuable summary of a work and makes the article
doubly useful. It is with this idea in mind that these questions
and answers have been supplied. They are collected under separate
heads so that desired questions and answers can easily be found.

BATTERY
Life
Q. What is the normal limiting factor of the life of a storage
battery?

A. The number of discharges.

Q. What are the factors that tend to shorten the useful life
of a storage battery?

A. Charging at unnecessarily short intervals; overcharging;
charging at excessive rates; discharging too low; allowing to stand
discharged; discharging at excessive rate; short-circuiting of indi-
vidual cells or entire battery; sulphating of plates; lack of electrolyte
due to failure to replenish distilled w r ater; and corrosion.

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Charging

Q. What is meant by charging at unnecessarily short inter-
vals?

A. Recharging when only a part of the previous charge has
been utilized. For example, if the vehicle has a working radius
of sixty miles on a single charge of the battery, the latter should
not be recharged before 40 to 50 miles have been run. It should
not be put on charge again after having run only 10 to 20 miles.

Q. What is overcharging?

A. Charging for too long a time or at too high a rate.

Q. What is apt to be the result?

A. The temperature of the cells is apt to exceed the safe
maximum of 110° F.

Q. Why must so much care be taken to prevent the cells
from reaching or exceeding this temperature?

A. Because the heat expands the active material of the plates
and, if carried beyond this point, the material will be forced out
of the grids, ruining the battery.

Q. How can this be avoided?

A. By reducing the charging rate, or, if the temperature is
already too close to the danger point, by cutting off the current and
allowing the cells to cool before resuming the charge. If the ther-
mometer is not handy, test with the hand; the cells should not
feel uncomfortably warm.

Q. How can the length of charge necessary be determined?

A. By noting the point to which the battery has been dis-
charged and computing the number of hours necessary to return
that much energy to the battery at the normal charging rate.

Q. What is the normal charging rate of a battery?

A. This differs with the capacity and type of cell and a
plate or card giving it usually will be found on the car.

Q. Is this charging rate uniform throughout?

A. If there is ample time in which to charge at a uniform low
rate it is preferable, but for ordinary charging, when it is desired
to have the car ready for service again quickly, there is a starting
charge rate and a finishing rate.

Q. How can the proper rate be computed for a uniform
charge?

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A. An estimate of the amount of current necessary to charge
the battery fully must be made and this quantity divided by the
number of hours available. For example, if 84 ampere hours are
necessary and the time available is 12 hours, as overnight, the
average rate will be 7 amperes.

Q. What other factors influence a uniform charge?

A. If the charging circuit has a constant potential, or a mercury
arc rectifier is employed, the charging rate will automatically decrease
as the charge progresses, owing to the rising voltage of the cells.

Q. How high can the average starting rate be for an electric-
vehicle battery?

A. If the battery is fully discharged or down to at least 75
per cent of its capacity, it may be anything up to 35 amperes which
is about the maximum capacity of the average garage charging
apparatus. The battery may be put on charge with this starting
rate even if only half discharged, but the rate will have to be lowered
much sooner.

Q. Is it good practice to charge a battery when less than
half discharged?

A. No. At least 50 per cent and preferably 75 per cent of
its capacity should be utilized before recharging.

Q. What determines the end of the starting period of the
charge?.

A. The cells begin to gas freely.

Q. What is meant by "gassing", and is it injurious to the
battery?

A. In the conversion of lead from one form to another by
the passage of the charging current, hydrogen gas is evolved. When
charged at too high a rate or for too long a time the gas is generated
so rapidly that it bubbles out as if the electrolyte were boiling.
This is termed "gassing freely t \ Gassing in itself is not injurious
to the battery but it is an indication that conditions which will
cause injury, i.e., excessive charging and overheating, are present.

Q. When on charge at the starting rate, what should be done
when the cells begin to gas freely?

A. Reduce the charging rate to the finishing rate.

Q. How low should the finishing rate be?

A. Generally speaking, it should never exceed 10 amperes.

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ELECTRIC AUTOMOBILES 163

It is good practice to make it as much lower than this as possible,
consistent with completing the charge in the time available.

Q. Does the use of a high starting rate tend to injure the
battery?

A. Not if the rate is lowered to the finishing limit as soon as
the cells gas freely.

Q. Which is preferable, the employment of a low average
rate over a long period, ox a high starting and low finishing rate?

A. Other things being equal, the lower the charging rate used,
the longer will the life of the battery be. The adoption of starting
and finishing rates is simply to cut down the time of charging.
Q. How can the charge be hurried safely?
A. Start the charge at the maximum capacity of the charging
apparatus and as soon as the gassing point is reached, reduce it by
successive steps down to the normal finishing rate, bearing in mind
that the gassing point voltage must not be exceeded at a current
rate higher than 10 amperes.

Q. What should the charging rate be for overnight or unat-
tended charging?

A. The starting rate should be such that as it falls due to
the rise of the battery voltage, it will reach a minimum of 6 to 10
amperes when the charge approaches completion. With a mereury
arc rectifier or the usual incandescent lighting circuit (constant
potential) the proper starting rate ordinarily will be 18 to 20 amperes.
With some small motor-generators it may be as high as 35 amperes.
Q. Is it ever permissible to overcharge the battery?
A. It is beneficial to overcharge the battery at regular inter-
vals. Once a month the regular charge should be followed by an
overcharge at the finishing rate until the specific gravity of every
cell has stopped rising. (See Hydrometer Readings.)

Q. When a battery is to remain idle for some time, how should
it be treated?

A. Give it an overcharge before putting out of service and
after this charge flush .the cells right up to the covers with distilled
water to allow for evaporation and absorption of the acid by the
plates. Give it a freshening charge at the finishing rate once a
month. Before putting in service again discharge the battery and
then overcharge it.

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164 ELECTRIC AUTOMOBILES

Q. Will a battery give its usual capacity upon being put back
in service after a period of idleness?

A. No. It may not reach its usual maximum until it has had
several charges and discharges.

Q. What precautions should be taken before putting a battery
on charge?

A. Lock the control lever in the off position, open the battery
vents, and lift the hoods to give as much ventilation as possible;
see that there is no possibility of any loose pieces of metal, such as
tools, falling on the cells and that no naked flame or spark is brought
near it. Do not turn on the lamps or ring the bell with the charging
current on, as the increased voltage may burn them out.

Boosting

Q. What is meant by "boosting" the battery?

A. Giving it a short charge at a very high rate to increase
the daily mileage radius of the vehicle.

Q. What are the possible safe charging rates that may be
employed in boosting?

A. Any current rate that the cells can absorb without gassing
is not injurious. See Table VI, page 103.

Q. Can the Edison battery be boosted the same as a lead^ell
battery?

A. This is permissible at even higher rates, as the safe tem-
perature limit is 115° F. See the table on page 98.

Q. What are the limitations on charging generally?

A. The cells must never be allowed to gas freely or to become
too warm without reducing, or if necessary, stopping the charge
to allow them to cool.

Methods of Charging

Q. What methods of charging electric vehicles are usually
employed?

A. In garages that maintain more than one or two electrics,
a charging panel capable of charging several cars at once is employed.
This is either connected with the lighting mains where direct-current
service is available, or is fed by a motor-generator where the service
is alternating. For taking care of but one or two cars a mercury
arc rectifier for the alternating current is sometimes used.

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Q. Is the chemical type of rectifier ever employed for this
purpose?

A. Its efficiency is too low to make it practical for anything
but the small batteries of the lighting-and-starting systems of gaso-
line cars.

Q. In an emergency, can a vehicle battery be charged from
direct-current mains without the use of special charging apparatus?
A. This may be done by employing a bank of lamps in series-
multiple with an ammeter and a double-pole fused switch on the
mains. One wire is led directly from the switch to the charging
connection on the car; the other is connected first to one side of
the ammeter; from the other side of the ammeter a connection is
made to one side of the multiple lamp circuit. A wire from the
other side of the lamps completes the charging circuit. As all cars
are provided with a charging socket which will take only a special
plug, it may be necessary to connect the wires directly to the bat-
tery terminals. Sufficient 32-c-p. carbon-filament lamps must be
employed to give the proper amount of current; a smaller size may
be used just as well but more of them will be required. At least
ten of the larger size will be necessary as they consume approxi-
mately 1 ampere each, thus giving a charging current of 10 amperes.
For the higher rate permissible for starting the charge, twenty to
thirty of these lamps may be necessary. When the battery begins
to gas on this rate, some of the lamps must be removed, to cut
down the current. If a rheostat is available, it will be found much
more convenient; it should be connected in series with the ammeter
in place of the bank of lamps.

Q. What precautions must be observed in emergency charg-
ing?

A. Only direct current can be used; its polarity must be
determined so that the positive side of the circuit is connected to
the positive terminal of the battery. This can be done by inserting
the bared ends of two wires connected to the mains in a glass of
water, keeping the wires separated as much as possible. The wire
from which the greatest amount of gas rises is the negative. As
the charging plug probably will not be available, care must be taken
to see that the wires are connected to the battery terminals so that
all of the cells are in series. To do this it will be necessary to trace

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166 ELECTRIC AUTOMOBILES

the connections between the two sections of the battery under
the front and the rear hoods of the car. Thirty-ampere fuses should
be provided at the switch.

The hoods must be lifted and the vent plugs of all the cells
v>pened. Unless a hydrometer or a voltmeter is available for testing
the state of charge, charging must be discontinued when the cells
begin to gas freely after the current has been reduced to the finishing
rate, which should not exceed 10 amperes. In case the car is pro-
vided with an ampere-hour meter, this maybe relied upon to indi-
cate when the battery is sufficiently charged. The instructions
regarding direct current and its polarity naturally apply to charging
under any conditions, but when the regular charging panel and
the charging-plug connection are available, no special precautions
are necessary, as the charging plug can only be inserted in its socket
the right way.

Discharge

Q. How far can a storage battery be discharged safely?

A. Its voltage should never be allowed to drop below 1.170
volts per cell.

Q. Has the rate of discharge any effect on the capacity of
the battery?

A. The capacity of the battery will fall off as the discharge
rate increases. For example, a 100-ampere-hour battery will give
5 amperes for 20 hours but it will not give 50 amperes for 2 hours.

Q. How far should the battery be discharged before recharg-
ing?

A. At least 50 per cent of its capacity, and preferably 75 to
90 per cent, provided it is to be recharged as soon as this point is
reach ed.

Q. Why is a discharge at a very high rate such as is caused
by a short circuit injurious?

A. The chemical reconversion of the active material of the
plates in producing the current takes place so quickly that their
temperature rises abnormally, causing them to "buckle".

Q. Is it ever necessary to discharge the battery down to zero?

A. Its condition will be improved if discharged to this point
at intervals of about a month.

Q. How can this be done?

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ELECTRIC AUTOMOBILES 167

A. Connect the battery terminals through a rheostat so that
the discharge will be limited to the normal slow rate. This is usually
done after the battery has been discharged in service down to 80
to 90 per cent of its capacity. Immediately after reaching 1.170
volts per cell on discharge, it must be recharged.

Q. Why must a battery never be allowed to stand discharged?

A. In this condition what is known as "local action" between
the plates takes place and they become sulphated.

Q. What is sulphating?

A. The lead sulphate evolved during the discharge will harden
on the plates if the battery is allowed to stand discharged.

Q. How can a sulphated battery be brought back to good
condition?

A. By continuous charging for a long period at a low rate,
but at a higher voltage than usual, as the latter tends to break down
the coating of sulphate on the plates.

Q. What indication is there of sulphating, and how can it
be determined to what extent it has taken place?

A. The cell otherwise being in good condition, it will be
indicated by loss of capacity, and the degree to which the latter
has fallen off will afford a measure of the extent of the sulphating.

Q. How long must the charge be continued to remedy this
condition?

A. Depending on the extent to which the plates are covered
with the hard coating of white lead sulphate, it may require any-
where from 24 hours to a week or more.

Q. Why cannot a battery be allowed to stand idle without
being recharged at regular intervals?

A. Because the cells tend to discharge when standing idle,
owing to the unstable nature of the chemical compounds which
represent the stored energy.

Electrolyte
Q. Of what does the electrolyte of a storage battery con-
sist?

A. A solution of distilled water and chemically pure sulphuric
acid.

Q. How is it mixed?

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168 ELECTRIC AUTOMOBILES

A. By using a porcelain, glass, earthenware, or wooden vessel
and pouring the acid into the distilled water very slowly, as the
chemical combination of the acid and water evolves a great amount
of heat.

Q. Why should water never be poured into the acid?

A. It will spatter about with explosive force and the acid
is extremely corrosive, causing serious burns wherever it touches.

Q. How is the proper proportion of acid to water to form
electrolyte determined?

A. With the aid of the hydrometer. The proportions of
acid to water are 1 :4f for 1.200 sp. gr. and 1 :3 for 1.275 sp. gr. See
Hydrometer Readings.

Q. Is it ever necessary to add electrolyte to the cells?

A. Very rarely. A battery should go from one washing to
another without any necessity of adding electrolyte.

Q. How should losses by evaporation be. made up?
* A. By the addition of distilled water, rain water, or melted
artificial ice.

Q. How often should distilled water be added?

A. The height of the electrolyte over the plates should be
noted every time the battery is charged. It should always be kept
1 to i inch over the plates.

Q. Does the temperature of the electrolyte have any effect on
the battery action.

A. It might have. Extremes of temperature affect the specific
gravity of the electrolyte and should be avoided.

Q. Why should ordinary water or ordinary commercial acid
not be used for electrolyte?

A. Owing to the impurities they contain which will affect
the active material of the plates.

Q. How can the presence of impurities in the electrolyte be
determined?

A. By the odor noticeable on charging and by the discolora-
tion of the positive plates. Hydrogen gas has a distinctive odor
which will be recognized readily after a few times.

Q. Is the electrolyte of the Edison cell the same as that of
the lead cell?

A. No. It is an alkaline solution of potash and water.

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ELECTRIC AUTOMOBILES 169

Q. Is it ever necessary to add new electrolyte to an Edison
cell?

A. Nothing but distilled water should be added.

Voltage

Q. Why is it necessary that the charging-current voltage
should exceed that of the battery?

A. Because the voltage of each cell increases as the charge
progresses and unless the charging current were at a higher voltage
it could not overcome that of the battery. The battery would
then "reverse" until its voltage equalized that of the charging
current.

Q. How much should the charging voltage exceed that of
the battery?

A. See Table II, page 85.

Q. Is the voltage of the Edison battery the same as that of
the lead type?

A. No. For charging voltages, see the table on page 97.
Q. Is the voltage a good indication of the condition of the
cell, and how does it vary?

A. Next to the specific-gravity reading, the voltage affords

the best test of condition. The voltage varies from 1.170, when

completely discharged, to 2.55 volts per cell, when fully charged.

Q. How must voltage readings be taken?

A. Only when the battery is either charging or discharging.

Readings with the battery idle are valueless.

Q. Does the voltage vary with conditions other than that of
the state of charge?

A. Temperature and the age of the cell will cause a variation.
' The higher the temperature and the older the cell, the lower the
voltage will be for the same state of charge.

Q. Which affords the better indication of the state of charge,
the voltage or the specific gravity of the electrolyte.

A. The specific gravity of the electrolyte. See Hydrometer
Readings.

Hydrometer Readings

Q. What is a hydrometer, and how is it used?

A. It is an instrument for determining the specific gravity of

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170 ELECTRIC AUTOMOBILES

a liquid. For storage-battery use, it is combined with a syringe
so that some of the electrolyte may be drawn off for a test.

Q. What is the specific gravity of a liquid?

A. Its density as compared with distilled water which is
unity in the specific-gravity scale.

Q. Are hydrometers ever calibrated in any other standard?

A. Yes, the BaumS scale. See Table IV, page 93, for com-
parative readings.

Q. Why is the hydrometer test employed for the storage battery?

A. Because it affords the best test of the condition of the cell.

Q. What should the electrolyte test when the cell is fully
charged?

A. 1.270 to 1.280.

Q. How low may it be permitted to run?

A. As low as 1.250 in a fully charged cell.

Q. How should the test be made and how often?

A. By withdrawing sufficient of the electrolyte in the syringe
to float the hydrometer. Note the reading and return the elec-
trolyte to the same cell; test each cell the same way and never
put the electrolyte from one into another cell. The test should
be made once every two weeks.

Q. How close should the readings of the different cells be
to be considered uniform?

A. Within 25 points on the scale; i.e., no cell in a battery
should be below 1.250 or above 1.275 when it is fully charged.

Q. What do the various readings indicate?

A. A specific gravity of 1.150 indicates that the battery is
practically discharged; below 1.150, completely discharged or
"run down"; above 1.200, more than half charged.

Q. Is it ever permissible to< bring up the specific gravity of
a cell by adding electrolyte?

A. No. It will do no good and is apt to cause great harm.
The only way it should be raised is by charging the cell.

Q. When some cells have a much lower reading than others,
what should be done?

A. Such cells first should be charged separately at a low r rate.
If its specific gravity increases on charge, it simply indicates that
the cell has been discharged lower than the others and needed

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ELECTRIC AUTOMOBILES 171

additional charging. When it has been brought up to the others,
the whole battery may be charged.

Q. In case the electrolyte of such a cell does not increase
on charge and the cell does not increase in temperature, what is
the trouble?

A. The gravity of the electrolyte has been lowered by excessive
additions of water to compensate for leakage or similar cause.

Q. When putting new electrolyte in cells after washing them
out, what precaution must be observed?

A. The new electrolyte must be of the same specific gravity
as the old.

Q. Can the specific-gravity test be employed with the Edison cell?

A. No. As its electrolyte does not vary in this respect with
state of charge, the voltage test must be employed.

Q. Does the temperature affect the hydrometer reading?

A. It will be lower at low temperatures, and should be watched
rather carefully. Note the variation between 30° F. and 100° F.
in Table III, and study its temperature effect in Part I.

Battery Jars

Q. Of what are the battery jars composed?

A. Usually hard rubber in the case of the lead cell, and stamped
steel for the Edison cell.

Q. To what faults are lead-cell jars usually subject?

A. Leakage caused by not having the battery firmly clamped
in place. This permits movement of the cells and one or more of
them is apt to become cracked.

Q. How can a leaky jar be recognized?

A. Leakage due to cracks in the jar usually is very gradual,
but it will be noted that a leaky cell requires refilling oftener than
the others. After a short period its specific gravity will differ
from that of the others, owing to loss of electrolyte.

Connectors

Q. How can the lead straps and piHars forming the connectors
be kept in good condition?

A. By wiping them and the tops of the jars dry with a clean
rag after charging. If the battery has "gassed" strongly, dip the
rag in a solution of ammonia and water as the gas carries with it

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172 ELECTRIC AUTOMOBILES

a fine spray of electrolyte and the acid will cause corrosion unless
counteracted. A good preventive of this corrosion is to smear the
entire tops of the jars and the connectors with a light coating of
vaseline.

Q. When a cell has to be disconnected for any reason, how
is it reconnected to the remaining cells?

A. By burning the lead strap together if it has been cut, or
burning it to the pillar.

Q. In case the lead strap cannot be burned at the time, is
it ever permissible to use any other connector?

A. Heavy copper wire or a strip of copper or brass may be
soldered or bound on, but it should be removed as soon as possible.

Washing the Battery

Q. What is meant by "washing" the battery, and why is it
necessary?

A. Washing a battery involves cutting the cells apart, washing
the elements and the jars, and reassembling with new separators
and new electrolyte. It is necessary to prevent the accumulation
of sediment in the mud space of the battery from reaching the
bottoms of the plates; this sediment is the active material shaken
from the plates and, , as it is a good conductor, it would cause a
short circuit and probably ruin the battery.

Q. What are the elements of a battery?

A. The positive and negative groups of plates. The positive
is a dull red and the negative a grayish color.

Q. How often is it necessary to wash a battery?

A. This will depend on the type of jar and the age of the
elements. With the modern style jar having an extra deep mud
space, it will probably not be necessary to wash the battery until
it has seen two or three seasons' service. With the older form in
which the space allowed for sediment is much less, washing may be
necessary once a season. As the battery ages it will be necessary
to wash it oftener.

Q. What other causes besides the type of jar and age influence
the frequency of washing?

A. The treatment the battery has received. If it has been
abused, active material is forced out of the plates much sooner.

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ELECTRIC AUTOMOBILES 173

Q. How can the necessity for washing be determine4?

A. The presence of a short circuit in one of the cells. Cut
out the cell and open it. If the short circuit has been caused by
an accumulation of sediment, the others are in practically the same
condition and will soon become shorted also.

Q. How is a battery washed?

A. By cutting the cells apart, unsealing them, and lifting out
the elements, which immediately should be immersed in a wooden
tub of clean pure water. The separators are then lifted out and
the positive and negative groups of plates separated and marked so
that they may be put back in the same cells. Before disposing
of the old electrolyte, its specific gravity should be noted. The
plates should be washed in copious running water for several
hours, never allowing their surfaces to become exposed to the air.
Reassemble with new separators, fill jars with fresh electrolyte of
the same specific gravity as that discarded and keep elements under
water until ready to place in jars, which should then be sealed and
the lead connectors burned together again. Give a long slow charge
after reassembling.

Q. Why should lead connectors be employed, and why is
it necessary to burn them together?

A. Any other metal will quickly corrode. Burning is neces-
sary to make good electrical connection, except where bolted con-
nectors are fitted.

Q. Is it ever necessary to wash out an Edison battery?

A. No. The cells are permanently sealed as the active material
cannot escape from the containers.

Efficiency

Q. What is the efficiency of the storage battery?

A. About 80 per cent under favorable operating conditions.
See Fig. 11, page 27.

Q. What affects the efficiency of the battery?

A. Sulphating; very low temperatures; loss of electrolyte;
dropping of active matter from the plates; partial internal short
circuit between the plates; use of impure water; failure to keep
properly charged and to discharge fully at regular intervals; and
undercharging and overcharging.

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Q. Is the efficiency of the battery affected by temperature
changes?

A. When the weather is very cold, the efficiency of the battery
is cut down substantially, and this will be very perceptible by the
reduced mileage available on a charge on the coldest days of winter.

Q. What instruments should be kept handy for testing the
battery?

A. A hydrometer syringe, a good thermometer, and a low-
reading voltmeter.

Q. What other causes will tend to reduce the efficiency of
the battery?

A. The presence of impurities in the electrolyte caused by
using ordinary water or commercial sulphuric acid.

POWER USAGE
Motor Commutator

Q. What attention is necessary to keep the motor of an
electric vehicle in good running condition?

A. The commutator and brushes should be inspected at
regular intervals. If the commutator is discolored and dirty, it
should be wiped off with a clean rag moistened in good lubricating
oil but very little of it.

Q. If this does not remove the discoloration, what should be
done?

A. Take a strip of No. 00 sandpaper, the width of the com-
mutator, jack up one rear wheel, run motor slowly on first speed,
and hold sandpaper to commutator. If this does not smooth
commutator off to a uniformly clean surface, it will be necessary
to remove armature and take a light cut off the commutator in
the lathe to remove any depressions or ridges. Smooth down with
sandpaper after turning off.

Q. Is the commutator discolored when it shows a bluish
metallic tinge?

A. No. It is then in the best running condition and should
not be touched with sandpaper. Discoloration is black and usually
consists of an accumulation of dirt and oil, or it may be caused by
sparking at the brushes.

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Q. Does a commutator need oiling?

A. No more than can be applied by wiping with a clean
oiled rag.

Q. When a commutator is worn down, what should be done
with it?

A. Turn down in a lathe and smooth with sandpaper, as above.

Brushes

Q. What is the cause of sparking at the brushes?

A. Uneven contact on the commutator; weak brush-holder
springs; an accumulation of carbon dust and oil on the commu-
tator; running the motor under excessive overload; or a short-
circuited or grounded armature coil.

Q. What is the usual remedy?

A. "Sand in" the brushes, by placing a strip of No. 00 sand-
paper on the commutator, face up. Jack up a rear wheel and have
an assistant turn it by hand to turn the motor over. The brush
should be sanded down to a close and uniform fit over its entire
surface at the point of contact with the commutator. Proceed
in the same way with each brush. If, with a clean and smooth
commutator, this does not remedy the trouble, see if the brush-
holder springs are holding the brush firmly against the commutator.
Never use coarse sandpaper or emery.

Q. What does excessive sparking at adjacent commutator
bars indicate?

A. A short-circuited or open armature coil.

Q. How often should brushes be replaced?

A. When they have worn dowTi to a point where the spring
can no longer press them against the commutator properly; this
rarely will be oftener than once in a season.

Q. Is it permissible to replace worn brushes with any standard
carbon brushes that will fit the holders?

A. The motor will operate with such brushes but this should
not be done if it can be avoided, and then only temporarily — new
brushes supplied by the maker of the car being inserted as soon as
they can be obtained.

Q. Is a "carbon brush" a fixed quantity, or do they differ
particularly?

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176 ELECTRIC AUTOMOBILES

A. There are hundreds of different carbon brushes and prob-
ably no two are exactly alike; their resistance and their hardness
both differ and they are made in a great variety of shapes to fit
different holders, so that no brushes except those supplied by the
maker of the car should be used as replacements. Trouble is bound
to follow, otherwise.

Controller

Q. What is the function of the controller?

A. To vary the amount of current supplied to the motor and
thus vary the speed of the car.

Q. How many types of controllers are there in use on electric
cars?

A. Two general classes: one in which the operation is manual,
i.e., the actual closing of the various switches representing the
different steps in the control is carried out by moving a lever by
hand; while in the other, known as a magnetic controller, shunt
circuits operated by push buttons are utilized to energize electro-
magnets which in turn close the actual switches.

Q. What faults are to be looked for in the manually operated
controller?

A. Poor contact of the switch fingers, due to loosening of the
holding screws or weakening of the springs; burned contact fingers
or segments, usually due to the same causes.

Q. How can they be corrected?

A. By cleaning with fine sandpaper and if the finger does not
make uniform contact over its entire surface, bending slightly to
make it do so. These fingers usually have curved up ends which
cause them to engage the segments of the drum and stay in the
position to which they are moved. Care must be taken in bending
them, not to bend down too far, as the finger is then apt to catch on
the segment or contact plate instead of riding over it. If the finger
is making good contact all over its surface, it will not be possible
to insert a thin piece of paper between it and the segment; nor, if
inserted by lifting the finger, can the paper be pulled out. It
should hold fast and tear when an attempt is made to draw it out
from under the finger. There is danger of short-circuiting if the
adjustment of the fingers is not carried out properly.

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Q. What should be done before attempting to do any work on
the controller?

A. Disconnect the battery and wrap the terminals of the
cables with friction tape so that they cannot make electrical contact
with any metal parts.

Q. What faults are apt to occur with the magnetic type of
controller?

A. Broken or loose connections either at the push-button end
of the control or at the electromagnets. The switches actuated by
the magnets are usually fitted with carbon contact blocks which will
give service for a long while without any attention. In time, how-
ever, the faces of the blocks are likely to become burned or pitted
and will need squaring up.

Q. When the car refuses to run, the battery being in good
condition, is the controller necessarily at fault?

A. This does not always follow, as there may be a broken
connection between the battery and the controller or between the
latter and the motor; or the motor brushes may not be making con-
tact with the commutator.

Q. In case the car will run on certain speeds but not on others,
what is the cause?

A. Either the contact finger representing the speed in question,
or some of the contact fingers below it, i.e., in the order of closing
the circuit, may not be making contact. Each contact finger is not
an independent unit but often depends upon those below it in the
order of closing the circuits. For example, if a car having five
speeds will run on speeds 1, 2, and 3, but not on speeds 4 and 5, the
trouble may be due to poor contact of fingers 2 or 3.

Q. When the car will run forward but not backward, what is
the cause?

A. Usually failure of the reverse switch to operate, and this
naturally is the case also where it will run backward but will not
run forward.

Q. What is a reverse switch, and how does it operate?
A. It is a double-pole double-throw switch with cross-connec-
tions; i.e., if the connections at one side of the switch are positive-
negative, they will be negative-positive on the other side. By
shifting the switch from one set of contacts to the other, the polarity

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of the battery with relation to the motor is altered and the direction
in which the current passes through the motor is reversed. This
will cause it to start in the opposite direction to which it would run
with the switch in the other pair of contacts. Once started, the
operation of the motor is the same, regardless of the direction in
which it is running.

Q. Does the controller provide as many speeds backward as
forward?

A. Not as a rule; it is neither necessary nor safe to run the car
backward at high speed, so that fewer reverse speeds are provided.

Q. Where is the reverse switch usually located?

A. In some cases, it is combined with the controller and this
is particularly the case with the magnetic type; in others, it is
entirely separate. For example, on the Ohio, the reverse is in the
contactor box of the controller; on the Anderson, it is located at the
foot of the control mast and is accessible from the outside by the
removal of a small plate.

Q. Is it necessary to lubricate the controller?

A. The bearings should be oiled at regular intervals the same
as any other moving parts, but owing to their limited and slow
movement but little oil is required. The contact fingers should also
be lubricated; in some cases, as on the Anderson, special provision
is made for this in the form of oil pads which should be saturated
with oil once in six months.

Instruments

Q. What are the functions of the ammeter and voltmeter on
the electric vehicle?

A. The ammeter has a double reading scale, the needle moving
to the left to show the amount of current going into the battery on
charge, and to the right to indicate the amount of current used by
the motor in driving the car. The voltmeter indicates the total
voltage of the battery and shows the condition of charge, as the
voltage accurately checks the amount of energy in the battery.

Q. When should such readings be taken?

A. Only when the battery is being charged or discharged, as in
running the car. Instrument readings with the battery idle are of
no value.

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Q. What does an erratic jerky movement of the voltmeter
needle indicate?

A. The presence of a loose connection which is making contact
at times and at others is being shaken loose.

Q. What is the trouble when the voltmeter gives no reading?
A. A break in the circuit between the battery and the instru-
ment.

Q. What should the voltmeter read when the battery is fully
charged?

A. The equivalent of 2.55 volts per cell while the battery is

charging. The moment the charging circuit is opened, the voltage

will drop off somewhat. For a 40-cell battery this reading should

be 100 volts or a little over at the completion of the charge and before

the charging circuit is broken. When the needle indicates only 68

volts, the battery is exhausted; the reading should not be allowed

to go below 76 volts for a battery of this number of cells, and in the

same proportion for a greater or lesser number, i.e., the equivalent

of 1.9 volts per cell.

Q. Are the instruments liable to defection in service?
A. The vibration and pounding due to running over uneven
pavements are extremely severe on a delicate instrument. If the
ammeter fails to register when the vehicle is started, examine the
connections; see that the needle has not become bent so as to bind
it, or see whether it appears to have been shaken out of its bearings,
though this rarely will happen. To make certain that the instru-
ments are correct, they should be checked at least once a season by
comparing with a standard instrument and any variation found
allowed for in making subsequent readings. This is particularly
important with the voltmeter on which a slight variation would
give a misleading indication of the state of the battery, as a differ-
ence of two or three volts would make it appear that it was fully
charged before this was actually the case, or nearer exhaustion than
in reality.

Q. When the voltmeter needle drops to zero and the car will
not run, what is the cause?

A. Trouble in the battery such as a short circuit, or a break in
the battery wiring such as would be caused by a broken connection.
See that the battery is properly connected and all connections in the

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circuit are clean and tight. Examine the level of the electrolyte in
all the cells and replenish with distilled water, if necessary. Look
for cracked or broken jars where electrolyte is very low in a cell.

Q. When the voltmeter reads normally, but the ammeter does
not register and the car will not run, what is the trouble?

A. Most of the late-model electrics are provided with a cut-
out operated by the brake; see that the brake is released all the way
and that the cut-out is operating to close the circuit. Examine the
contacts of the latter and all the contacts and connections of the
controller. Do the same for the reverse switch. Note whether
brushes are making good contact with the commutator.

Q. When the ammeter reading is very high, but the car will
not start, what is apt to be the cause?

A. The brakes may be binding or something may have gone
wrong with the universal joint or with the gears or bearings of the
differential. Jack up one wheel and see if it can be turned freely
by hand. If it cannot be turned and the brakes are free, remove
the rear axle and examine the universal joint, gears, and bearings.

Q. If the car runs, but the ammeter reading is unusually high,
what is the trouble?

A. The brakes may be dragging; see that they release fully
when the pedal is all the way back. See that the front wheels are
properly lined up; they are usually given a camber of J to f inch, i.e.,
when viewed from the front they apparently "toe-in". A plumb
line held at the top of the tire should strike the floor that distance
away from the tire. The front wheels may not be in line with the
rear wheels; this usually is caused by running against a curb or
, dropping into a bad hole, which bends the steering connections. If
the wheels do not line up properly, adjust the steering connections;
it may be necessary to bend a part back to bring the wheels into
line, and this should be done cold. Examine the differential and all
bearings and driving connections to see that they are properly lubri-
cated. See that the tires are properly inflated and that only "elec-
tric" tires are fitted. (See Tires.)

Q. When the reading of the ammeter is normal, but the speed
and mileage are low, what is the trouble?

A. The battery or the motor may be at fault. (See Low
Mileage.)

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Q. What is considered a normal ammeter reading?

A. On smooth hard pavements and in good weather, a car
provided with a40-or42-cell battery should draw about 30 amperes
on its highest regular speed after it has finished accelerating and is
running easily. With a battery of a smaller number of cells, this
will be higher. It will also be much higher on the accelerated speed
which is only designed for employment in emergencies.

Q. Are any instruments other than the voltameter ever
employed?

A. Many cars are fitted with ampere-hour meters which show

how many ampere-hours have been put into the battery on charge

and how much has been taken out in running. They give a direct

reading of the amount of energy available in the battery at all times.

Q. To what faults are such instruments liable?

A. Broken connections, loose or dirty connections, or a broken

wire are the only causes of failure that can be remedied in the garage.

If the instrument is not working properly, due to any other cause,

it will be necessary to return it to the makers.

Wiring

Q. Is trouble often experienced with the wiring of an electric
vehicle?

A. Very rarely; the cables are usually of ample size to carry
the loads for which they are designed, i.e., the lamps or the motor,
and they are protected by steel armor in the majority of instances.
On older cars on which adequate protection to the wiring was not *
always the rule they may be found to have suffered at times from
mechanical injury.

Q. What faults are most apt to occur in the wiring?

A. Loose or broken connections at the terminals, whether at
the motor, battery, controller, or* reverse switch. This is due simply
to the vibration and jolting, and when trouble is experienced in the
running of the machine on the different speeds, the various connec-
tions should all be examined, first, however, disconnecting the
battery as mentioned for inspection of the controller.

Q. Are there any grounded connections on the electric vehicle,
as in the case of lighting-and-starting systems on the gasoline car?

A. No. All circuits are of the two-wire type and considerable

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182 ELECTRIC AUTOMOBILES

care is taken to insulate all cables and wires from the chassis of the
machine. Frayed ends of stranded cables may sometimes cause a
ground which will announce its presence by blowing the fuse on
that particular circuit.

Q. Is there any way of detecting the presence of loose con-
nections except by inspection?

A. A jerky movement of the voltmeter needle indicates that
the circuit is being made and broken at intervals, as would be caused
by the vibration at a loose connection.

Fuses

Q. Where are the fuses located, and what circuits on the
electric car are protected by fuses?

A. Usually on a small panel board or junction box on the
forward face of the dash under the hood; sometimes under the floor
boards (consult the wiring diagram). Only the lamp circuits are
protected by fuses, as the load imposed on the motor in starting
the car in heavy snow or similar bad conditions w T ill often cause the
ammeter needle to go the limit of its travel, so that fuses on the
power circuit would not be practical.

Q. When a fuse blows, what does it indicate?

A. Usually that a lamp has burned out and in doing so has
caused a temporary short circuit on that line. This may also be
caused by a ground or short circuit in the wiring, generally at the
lamp socket, as the wires themselves are usually well protected from
injury. Before replacing a burned-out lamp, inspect the terminals
and connections.

Q. If the same fuse blows repeatedly, where should the cause
be sought?

A. Should inspection show that none of the connections at
the lamp or the junction box are at fault and the wiring is intact,
see if the battery connections are properly made, if the battery has
been overhauled. See that the proper type of lamp is being used
for replacement and that it is of the proper voltage.

Lamps
Q. What is the voltage of the lamps usually supplied on the
electric car?

A. Generally that of the total nominal voltage of the battery,

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i.e., on a car having a 40-cell battery, 80-volt lamps would be used.
On cars having what is termed a double- voltage system (Ohio), the
battery being coupled in two units of 20 cells each connected in
parallel to give certain speeds, instead of employing a resistance,
40-volt bulbs are used.

Q. Why should the lamps never be lighted while the battery
is on charge?

A. The excess voltage may burn them out or blow the fuses.
Q. What causes one lamp to burn much brighter than the other?
A. A bulb of higher voltage may have been used as a replace-
ment in one socket, or one of the bulbs may be much older than the
other. The filament increases in resistance with age so that it takes
less current and gives correspondingly less light.
Q. If a lamp fails to light, what is the cause?
A. The fuse on its circuit may have been blown out, or the
lamp itself may not be making good contact in the socket; the
wiring may have become grounded or short-circuited, usually at the
lamp socket. The bulb may be burned out, or its filament broken.

Low Speed and Mileage

Q. What are the chief causes of low mileage per charge?

A. (Battery) The battery may not have been fully charged
before starting out; the level of the electrolyte in the cells may be
too low, or there may be a leaky jar. The battery may have lost
a considerable percentage of its efficiency through abuse or age, or
it may be new. Full mileage is never obtained on the first run or
two with a brand new battery or a battery that has just been over-
hauled; it will not give its normal output until it has been charged
and discharged four or five times. The battery may not be connected
up properly; check with the wiring diagram.

(Motor) See that the commutator is clean and bright, that
the brushes are making good contact with it over their entire sur-
face, that they have not been worn down too far and that the springs
have sufficient tension to keep them firmly pressed against the com-
mutator. See that all connections are clean and tight. Examine
the armature connections and see that none have become broken or
short-circuited; this will usually be indicated by the condition of the
commutator and is at best a rare cause of trouble.

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184 ELECTRIC AUTOMOBILES

(Brakes) See that the brakes are properly adjusted and are
not rubbing against the drums at any point when fully released.
This will usually be indicated by a high ammeter reading.

(Lubrication) Neglect to keep the differential housing filled
to the proper level with the right kind of oil (worm drive), or with
the proper grease (bevel gear drive), and failure to lubricate the
motor and wheel bearings will increase the draft on the battery and
cut down the mileage. The use of grease in the differential of the
worm drive or the employment of a heavier grease than that recom-
mended by the maker for a bevel drive will do likewise.

(Controller) Note whether all the contact fingers of the con-
troller bear firmly against the segments and whether there is any
arcing at the contacts when they are operated. Clean and adjust
as explained under "Controller". Examine reverse switch or
switches (duplex drive) for the same causes of trouble.

( Tires) Underinflated tires or the use of a "gasoline" type of
tire, even on but one of the wheels, will cut down the mileage very
perceptibly. Nothing but electric-car tires should ever be employed,
and if tires intended for a gasoline car have been fitted, replace them.

(Driving) Low mileage is due as frequently to improper
handling of the car as to any other cause. Excessive use of the
accelerator speed causes an abnormally heavy draft on the battery
and the mileage will be considerably reduced. Failure to take advan-
tage of grades to coast, or to shut off the power sufficiently in advance
of a stopping place to permit the car to come to a halt without more
than a gentle pressure on the brake pedal, will do likewise. Attempt-
ing to start before fully releasing the brakes will also waste a great
deal of power, if it does not result in badly burning the commutator
or burning out the armature windings. Making an unusual number
of stops and short runs in a day's use will cut down the mileage.

(Weather Conditions) The normal mileage per charge is based
on favorable road conditions and, as the latter are affected by bad
weather, the car will not run as far on a charge in rain or snow as in
dry weather. Wet pavements cause the driving wheels to slip in
starting, thus causing a loss of power, while the presence of snow or
mud on the streets will call for a greatly increased amount of power
to cover the same distance.

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STEAM AUTOMOBILES

INTRODUCTION

Development of Steam Engines. That steam could be employed
to produce mechanical motion was first noted in history about 130
B. C, but it was not until the seventeenth century that it found
practical application in the industries. The developments were com-
paratively slow, however, until James Watt (1769) developed his
engines to a point where they employed practically all the principles
of the modern double-acting, condensing steam engine.

With these rapid inprovements came the idea of using the steam
engine as a means of road locomotion, and in the opening years of the

Fig. 1. Early Steam Carriage Built by Cugnot (France) in 1770

nineteenth century such machines were actually built and known as
"road locomotives", Fig. 1. These machines might be called the
forerunners of the steam automobile, although structurally they
more nearly resembled the later traction engines. Bad roads, great
weight, public opinion, and the development of railroads caused road
locomotives to drop out of sight until the real coming of the automo-
bile almost a hundred years later.

In the meantime the steam engine — both stationary and loco-
motive types— had reached a high state of development and hence
many of the early automobiles carried this type of power plant.

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Later improvements were made and are still being made along lines
peculiar to steam automobile construction. Although during the
last few years the steam car has not kept pace in numbers with
other types of automobiles, it has certain characteristics, such as
strong pulling powers at low speeds, capacity for big overloads, and
ease in driving on the road, which make it especially useful under
some conditions, the success of the London steam omnibuses being a
good example.

CHARACTERISTIC FEATURES OF STEAM CARS

In the modern steam automobile the power plant is made up of
the same general units as make up the stationary power plant, the
only difference being the extreme compactness necessary and the
development of the great flexibility required to meet the sudden
changes in load conditions. With both plants there must be a supply
of fuel, a means of burning it, a boiler or steam generator, a supply of
water, an engine, and various means of controlling the amounts of
fuel, water, and steam.

Location of Engine* With steam automobiles there is no uni-
formity of practice as to the placing of the different units in the

Fig. 2. Plan View of Stanley Steam-Car Chassis
Courtesy of Stanley Motor Carriage Company, Newton, M as$achusett*

running gear or chassis. For instance in the Stanley, Fig. 2, the
boiler is under a hood in front of the driver and the engine is geared
directly to the rear axle. In the case of the White cars, Fig. 3, which
were built in comparatively large quantities from 1904 to 1910, the
engine was placed under the hood in front with a shaft running back
* to the rear axle. In the White car, a set of gears was also used in the

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STEAM AUTOMOBILES y 3

drive, by which the relation of engine to wheel speed could be reduced
to one-half the usual amount, thus doubling the driving effort, or
"torque". The White boiler was under the front seat. The new
Doble, Fig. 4, uses the same general arrangement as the Stanley. In

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the Leyland steam truck, Fig. 5, and the National busses, both of
England, the boilers are in front, the engines are under the floor
boards, with a countershaft and final chain drive, as in Fig. 5, or a
shaft drive direct to the rear axle.

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Boiler and Engine Types. Almost equal variation is found in
the types of boilers and engines. The difference between fire-tube,

Fig. 4. Side View of Doblc Steam-Car Chassis
Courtesy of General Engineering Company, Detroit, Michigan

water-tube, and flash generators is taken up in the section devoted to
boilers, while the engine types are taken up in their respective section.

Fig. o. Lcyland Steam Truck with Chain Drive to Rear Wheels
Courtesy of Lcyland Motors Company, Ltd., Englaiid

Some of the cars use the water over several times by condensing the
steam in coolers, or "condensers", placed at the front of the car. The

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STEAM AUTOMOBILES 5

White and Lane did this, and it is now done by the Stanley, Doble,
and most of the English steam cars and trucks. The Stanley, up to
1915, had no condensers, allowing the steam to escape into the air
after it had passed through the feed-water heater.

Simplicity of Control. As a general rule, the steam cars do not
employ a transmission for giving various forward-gear ratios and
a reverse. The extra heavy loads, as in starting, are taken care of
V>y lengthening the cut-off and by "simpling", terms w T hich will be
more fully explained later. Instead of running the engine always in
one direction and using a gearset for reversing the car, as is done on
gasoline automobiles, the engine is itself reversed by means of chang-
ing the timing of the valves through the aid of the valve gear, or
linkage.

This change of the valve-timing is used only at starting, reversing,
or under very heavy load conditions, all ordinary running being
accomplished with the cut-off in one position. The control of the
speed of the car, therefore, is accomplished under normal conditions
by changing the amount of steam going to the engine. The steam is
turned on or shut off by a hand-operated valve, known as the "throttle
valve", and this valve is turned by a lever, or second small wheel,
just above or below the steering wheel. Thus the actual driving of a
steam car consists of steering and operating the throttle. There are,
however, numerous gages, valves, etc., which have to be worked upon
when firing up, and which have to be given occasional attention on
the road; these w r ill be considered in detail in the following pages.

Having treated in a general way the different types of steam cars
and their parts, the theory underlying the behavior of steam will be
touched upon before taking up the details of construction and the
operation of the various units.

HEAT AND WORK
HEAT TRANSMISSION

All forms of energy, such a^; light, sound, electricity, and heat,
are believed to be different forms of vibration either of the molecules
of material substances or of the ether which is believed to pervade
all space.

Energy is indestructible, but any form of energy may be con-
verted into any other form. Steam engines are classed as heat

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6 STEAM AUTOMOBILES

engines since they are employed to transform heat energy into me-
chanical work. Heat may be transmitted from one body to another
in three ways, namely, by radiation and absorption, by conduction,
and by convection.

Radiation and Absorption. Radiation is the transfer of heat
from one body to another body not in contact with it. It takes place
equally well in air or in vacuo. The rate of heat transferred depends
partly on the distance separating the two bodies, and partly on the
nature of their surfaces. In general, light-colored and polished
metal surfaces radiate heat more slowly than rough and dark-colored
surfaces. The laws governing absorption are the same as those
governing radiation.

Conduction. Conductioh is the transfer of heat through the
substance of a body — solid or liquid — to other portions of the same
body, or to another body in physical contact therewith. Metals arc
the best conductors of heat, but some metals, such as copper, are
better conductors than others. Other solids, such as stone, wood, etc. ,
rank after the metals. Liquids are very poor, and gases still poorer,
conductors of heat. A vacuum is perfectly non-conducting, though
radiation may still take place through it.

Convection. Convection is the term applied to the absorption
of heat by moving liquids or gases in contact with heated surfaces.
If a blast of air be directed on a piece of hot iron, the iron cools far
more rapidly than it would in still air. The reason is that, as the air
is a poor conductor, its molecules do not transmit heat readily from one
to the next, but if each molecule on becoming heated is immediately
replaced, heat is rapidly transferred. This property of air of taking
up heat rapidly when blown over a hot surface is employed in
gasoline automobiles to cool the so-called "radiators". In reality, the
heat radiated cuts a small figure compared with that dispersed by
convection.

What has just been said regarding air is equally true of other
gases. It is also true of most liquids.

Relative Conductivity. Heat conducting qualities vary for
different substances. Silver, copper, and aluminum conduct heat
very rapidly, while asbestos is a poor heat conductor and is therefore
used around the outside of automobile boilers.

Expansion. Another heat property which has to be con-

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2/2 9

sidered in the selection of material for steam cars is that of expansion.
Some metals expand much more than others for each degree of rise
in temperature. Since brass and copper both expand under heat
much more than iron they are used in preference to iron in the con-
struction of expansion tubes, which are fully described later.

Temperature Measurement Scales. Temperature, which is the
measure of the intensity of heat, is expressed by means of divisions
called degrees on some thermometer scales. The
two thermometers in most general use are the
Fahrenheit and Centigrade; the former being the
more common in America and England for both
engineering and household use, while the latter
is used exclusively on the Continent.

Freezing of water occurs at 32° F. (Fahren-
heit) and boiling of water at 212° F. The scale
between these two points is divided into 180 equal
parts. On the Centigrade scale, the points of
freezing and boiling occur, respectively, at 0° C.
and 100° C, and there are, therefore, 100 equal
divisions between the two points, Fig. 6. Thus
it is seen that every 5 degrees Centigrade equal 9
degrees Fahrenheit.

Conversion of Scales. To convert readings in
one scale to readings in the other, the reading
given is substituted in the following equation:

-17.8*- =

°F-32
180

100

Fig. 6. Centigrade and
Fahrenheit Thermome-
ters, Showing Com-
parison

Thus, if a temperature is given as —5° C. it is
equal to 23° F.; 23° C. equals 73.4° F. Conver-
sion tables over large ranges are given in engineering handbooks,
such as Kent.

Absolute Zero. In engineering calculations the absolute zero and
the absolute scale are sometimes spoken of. This absolute zero, which
will be mentioned again, is taken as —270° on the Centigrade scale
and -460.6° on the Fahrenheit scale. Thus -5° C. equals +265° on
the C.-absolute scale and +483.6° on the F.-aboslute scale.

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LAWS OF QASES

Almost all substances expand with rise of temperature. Solids
expand least, and in some the expansion is imperceptible. Liquids
expand about as much as solids, sometimes slightly more. Gases
and vapors expand a great deal if free to do so.

Boyle's Law. Before considering the expansion of gases under
changes in temperature, let us see how they act when the temperature
is unchanged. A gas is perfectly elastic, that is, if not confined in any
way it would expand indefinitely. The attraction of gravity is all that
prevents the atmosphere surrounding the globe from dispersing into
infinite space. When air is partly exhausted from a closed vessel,
the remainder, no matter how small, expands so as to distribute itself
equally throughout the vessel.

If a cubic foot of air at atmospheric pressure be compressed
into one-half cubic foot without change in temperature, its pressure
will be precisely twice what it was before. In speaking of gas pres-
sures in this manner, it is customary to deal with absolute pressures,
that is, pressures above a perfect vacuum. Thus atmospheric pressure
at sea level is approximately 14.7 pounds per square inch, and a cubic
foot of air reduced one-half in volume will have an absolute pressure
of 29.4 pounds.

This relation of pressure and volume is expressed in "Boyle's
Law", which states that, so long as the temperature is unchanged,
the product of the pressure and volume of a given weight of gas is
constant. That is

PV = C

This is the most important of all the laws of gases.

Curve Expressing Boyle's Law Relation. Fig. 7 expresses the
relation between volume and pressure of a given weight of air starting
at atmospheric pressure and compressed to a pressure of 500 pounds
without change in temperature; also expanded to a pressure of
one pound absolute. Horizontal distances represent volumes, the
volume at atmospheric pressure being unity; and vertical distances
represent absolute pressures. To find the pressure of the air for any
volume greater or less than one, locate the given volume on the
base line, then, from this point, read up to the curve and find the
desired pressure by moving horizontally from the curve to the
scale at the left.

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Behavior of Gases with Changes of Temperature. As heat is a
mode of motion, it follows that when all heat is withdrawn motion
ceases, and the molecules, even of a gas, become fixed. From experi-
ments and theoretical considerations the absolute zero, representing
the absence of all heat, is believed to be —273° C, or approximately
— 460° F. In most theo-
retical studies of the
behavior of gases, tem-
peratures are reckoned
from absolute zero in-
stead of from the arbi-
trary zeroes of the con-
ventional thermometer.
When a gas of given
weight at an absolute
temperature of 273 de-
grees — that is, 0° C. on
the customary scale — is
raised in temperature one
degree without change
in pressure, its volume
is increased si *• A sec-
ond degree of added tern- votum*

perature increases its Vol- Fig. 7. Curve Showing Relation between Volume

* and Pressure of Air

ume the same amount,

and so on. In other w T ords, for each degree Centigrade of added tem-
perature its volume is increased y\j of its volume at 273° A.

If degrees Fahrenheit are taken instead of Centigrade, the
expansion is ? J ? of the volume at 32° F. for each degree of rise in
temperature. Five degrees C. equal nine degrees F.

If the gas thus heated is so confined that it cannot expand, it
will suffer an increase in pressure in the same proportion, that is, *4 y
of its pressure at 0° C. for each degree Centigrade. If the gas, instead
of being heated, is cooled, its shrinkage in the one case or its loss
of pressure in the other will follow the same rule as above. Theoret-
ically it follows that at —237° C. — absolute zero — the gas would
have no volume at all. Of course that is impossible, but at ordinary
temperatures the gases behave as if the assumption were true.

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HEAT TRANSFORMATION

Specific Heat. The temperature of a body and the heat it con-
tains are two different things. A gallon of water at 100° F. contains
twice as much heat as half a gallon at the same temperature. That
is to say, twice as much heat was imparted to it in raising it to that
temperature.

Like quantities of different substances at the same temperature
do not always contain the same quantity of heat. A pound of water
contains more heat than a pound of oil or alcohol at the same tem-
perature. It requires 7.7 times as much heat to raise a pound of
water one degree in temperature as a pound of cast iron.

The quantity of heat required to change the temperature of a
given weight of a substance one degree, compared with that required
to change the temperature of the same w r eight of water a like amount,
is called the "specific heat" of that substance.

Specific heat varies considerably for different substances, and for
different temperatures and states of the same substance. Thus the
specific heat of steam is much less than for water and varies slightly
as the temperature and pressure of the steam is varied.

British Thermal Unit. The quantity of heat required to raise
the temperature of one pound of water one degree F. is known as the
"British thermal unit" (B.t.u.). Another unit is the "calorie", which is
the quantity of heat required to raise the temperature of one kilo-
gram (2.2046 lb.) of water one degree Centigrade. One calorie equals
3.968 B.t.u. The B.t.u. is the unit generally used in this country
for engineering calculations. The latest investigations lead to
slightly different and more complicated definitions of the B.t.u.
from the one given above, but this is near enough for practical
calculations.

Heat Value of Fuels. The number of heat units liberated by
burning a pound of fuel varies for different fuels. The heat value for
fuels is determined by experiment, and by calculation when the
chemical composition is known. Due to the variation in the com-
position of commercial gasoline, different samples will give different
results, but for most calculations the figure of 19,000 B.t.u. Kerosene
has a slightly higher value.

Force. Force is defined as that w T hich produces, or tends to
produce, motion, and in practical work is usually expressed in units

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STEAM AUTOMOBILES 11

of weight, for example, pounds, kilograms, or tons. A force may
exist without any resulting motion, and therefore without work being
done. For example, the weight of any object represents the force of
gravity attraction between the earth and that body. The atmos-
phere exerts a pressure or force of approximately 14.7 pounds per
square inch at sea level.

Work. Work is done when force is exerted by or on a moving
body, and is measured by the product of the force into the distance
through which it is exerted. A convenient unit of work is the "foot-
pound", which is the work done in lifting a weight of one pound
against the force of gravitation a vertical distance of one foot, or
exerting a force of one pound in any direction through a distance of
one foot.

Power. Power expresses the rate at which work is done. If a
foot-pound of work is performed in a minute, the power is small.
If it is done in a second, the power is 60 times as great. The cus-
tomary unit of power is the horsepower, which is 33,000 foot-pounds
per minute. Whether a force of 33,000 pounds be exerted through
one foot of distance, or one pound be exerted through 33,000 feet in
the same time, the power is the same.

Mechanical Equivalent of Heat. Heat may be converted into
work or work into heat. Experiments have been made in which water
was agitated ia a closed vessel by means of paddles run by falling
weights and the resulting rise in temperature of the water carefully
determined. From these and other experiments, it has been ascer-
tained that one British thermal unit is the equivalent of 778 foot-
pounds of work. That is, a weight of one pound falling 778 feet, or
778 pounds falling one foot, develops sufficient energy to raise one
pound of water one degree F. in temperature. A horsepower, there-
fore, equals 42.416 B.t.u. per minute. The combustion of one pound
of either gasoline or kerosene liberates approximately 19,900 B.t.u.,
but the kerosene is heavier for equal bulk. One U. S. gallon of
gasoline weighs about 5.6 pounds; of kerosene, about 6.25 pounds.
The combustion of a gallon of kerosene per hour develops theoret-
ically about 49 horsepower but the actual amount of energy obtained
falls far short of this. Owing to heat losses in the boiler and exhaust,
and to radiation, etc., only a small fraction of this energy can be
converted into useful work.

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THERMODYNAMICS OF STEAM
Latent Heat. If water be heated in an open vessel it will reach
a temperature of approximately 212° F. (100° C.) and will then boil
away without further rise in temperature. The added heat is
absorbed in converting the water into steam.

It takes far more heat to convert water into steam than to raise
its temperature. A pound of water heated to boiling from 32° F.
absorbs only 180 B.t.u., but in boiling away at 212° F. it absorbs
966 B.t.u. additional. At atmospheric pressure the vol-
ume of the steam is 1645 times the volume of the water
whence it came. This bulk of steam must displace an
equal bulk of air, and part of the heat energy represented
by the steam has been spent in pushing back the air to
give it room. This will be made clearer from the sketch,
Fig. 8, showing a long tube open at the top and containing
a little water at the bottom. On top of the water is a
piston, supposed to be air-tight and without weight or
friction. If the water be boiled into steam, the piston
will be pushed upward against the atmospheric pressure
a distance equal to 1645 times the original depth of the
water. The work in foot-pounds thus done will be 14.7
times the area of the piston in square inches times the
distance in feet through which it has moved. Approxi-
mately 7.45 per cent of the heat imparted to the steam
represents work done against the atmosphere; the remain-
der is spent in overcoming the mutual attraction of the
molecules of water. The heat which has been absorbed
by the" change in state from w T ater to steam without
change in temperature is called the ' 'latent heat of vapor-
ization".

If a vessel containing water at 212° F., which is the
atmospheric boiling point, be put under the receiver of
an air pump and the air partly exhausted, boiling will
take place spontaneously without further addition of heat. At the
same time the temperature of the water will decrease, because part
of the heat contained in it has been absorbed by the conversion of
water into vapor. If the air pump keeps on working, the water will
boil continuously while its temperature steadily descends. If the

Fig. 8. Expan-
sion of Water
into Steam

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STEAM AUTOMOBILES 13

experiment be carried far enough, with the vessel so supported that
it can absorb little or no heat from adjacent objects, and if the
vapor given off be rapidly absorbed, for example, by placing a tray
of quick-lime or sulphuric acid adjacent, the water may actually be
frozen by its own evaporation.

This experiment shows that the boiling point of water — and
this includes other liquids also — is not a fixed temperature but
depends on the pressure. All volatile liquids when exposed to partial
or complete vacuum give off vapor; on the contrary, this vapor when
subjected to pressure partly re-condenses and a higher temperature
is needed to produce boiling. Under an absolute pressure of 147
pounds or 10 "atmospheres", the boiling point is 356.6° F. At 500
pounds absolute pressure the boiling point is 467.4° F. (242° C).

The "total" heat of steam at the boiling point corresponding
to a given pressure is the sum of its latent heat of vaporization and
the heat contained at the same temperature in the water from which
the steam was formed. The total heat of steam increases slowly, but
the latent heat diminishes nearly in proportion as the boiling point
rises. The space occupied by a given weight of steam diminishes
approximately in proportion to the increase in pressure. In this
respect the steam resembles a perfect gas without change of tempera-
ture in accordance with Boyle's Law. Tables showing the pressures,
temperatures, latent heat, etc., of steam are given in Kent and other
handbooks.

The experiment just cited of producing spontaneous boiling
in water by exhausting the air above it, may be duplicated with hot
water at any temperature and pressure. For example, the boiling
point of water under 100 pounds absolute pressure is 327.6° F.
If, in a boiler containing water at that temperature and pressure,
the pressure be reduced to 50 pounds by the withdrawal of steam, the
water will boil spontaneously, absorbing its own heat in doing so,
until it reaches a temperature of 280.9° F., which is the boiling point
for 50 pounds absolute pressure.

Cause of Boiler Explosions. Owing to the property of giving
off steam under reduction of pressure, every steam boiler constitutes
a reservoir of energy which may be drawn upon to carry the engine
through a temporary period of overload. In other words, the boiler
will give out steam faster than the fire generates steam, the difference

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14 STEAM AUTOMOBILES

being supplied from the heat stored in the water itself. This is an
exceedingly useful feature of the ordinary steam boiler. At the
same time, and for the same reason, it is a source of danger in case of
rupture of the boiler shell. If a boiler explosion involved simply
the release of the steam already formed it would not be so serious a
matter; but when a seam starts to "go" the adjacent portions are
unable to carry the abnormal strain put upon them, and the result
is a rent of such proportions as to release almost instantly the entire
contents of the boiler. The hot water thus suddenly liberated at
high temperature bursts into steam until the whole mass drops to a
temperature of 212 degrees, and this steam is many hundred times
the volume of the water from which it came. It is to this fact that the
violence of boiler explosions is due.

To take an extreme case, if a boiler bursts under 500 pounds
pressure, approximately thirty-seven per cent of the water it contains
will pass instantly into steam, and at atmospheric pressure the volume
of che steam will be over 600 times the volume of the entire original
liquid contents of the boiler.

Automobile boilers and steam generators are so designed as
to minimize the danger of explosion, and only ordinary care is needed
to insure entire safety.

Superheating. The foregoing paragraphs have dealt exclusively
with steam at the boiling temperature due to its pressure. Such
steam is called "saturated" fcteam. Steam will not suffer a reduction
of temperature below this point; if heat be absorbed from it a portion
will condense. On the other hand, steam isolated from the water
whence it came may be raised in temperature indefinitely. It is then
called "superheated" steam. The more it is superheated the more
nearly does it act like a perfect gas.

Superheated steam is preferred for power purposes to saturated
steam, for the reason that the latter condenses more or less, both in
the pipes on its way to the engine and in the engine itself. Steam
which condenses thus is a total loss, and it is more economical to add
sufficient heat- to it before it reaches the engine to replaces radiation
losses, etc., without cooling the steam to the saturation point. To
accomplish this in automobiles, the steam from the boiler is led
through one or more pipes exposed to the maximum temperature of
the fire. These pipes are called superheaters, or superheating pipes.

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STEAM AUTOMOBILES 15

MECHANICAL ELEMENTS OF THE STEAM ENGINE

General Details of Steam Engine Parts. In Fig. 9 a plan view
of a stationary steam engine is given, with the cylinder and valve
chest shown in cross section, and with the various parts marked by
letters. A view of a stationary engine is used because it is not so
condensed as an automobile engine, and the parts are therefore
easier to mark and pick out. The relations and names of parts are
the same in an automobile engine.

Fig. 9. Plan View of Typical Stationary Engino

A, Cylinder. B, Outer cylinder head. C, Piston rod. D, Crosshead. E, Connecting rod.
F , Crankpin. Q, Crank. H, Crankshaft. J, Eccentric. J, Eccentric rod. A", Eccentric
crosshead. L, Valve stem. 3f, Steam chest. N, Steam pipe connection. PP % Flywheels.
Q, Crosshead guides. R, Valve stem guide. 5, Engine frame. T, Stuffing box. U, Piston.
V, Wristpin. WW, Steam ports. X t Slide valve. Y, Eccentric strap. Z, Clearance space
between piston and cylinder head at end of stroke.

A is the cylinder to which steam is admitted through the pas-
sages, or ports, W W, which connect it with the steam chest M. The
opening and closing of these ports is accomplished by the movement
of the valve X. Because of its shape, the valve here shown is called
a D-slide valve. Other types of valves are piston valves and poppet
valves, names which explain themselves. The valve is attached to
the valve stem L and is guided by the valve-stem guide R. Motion
back and forth is given the valve by the eccentric /, which is a circu-
lar disk on the crankshaft, with its center offset from the center of
crankshaft H.

Returning to the cylinder, U is the piston, which is driven back
and forth by the steam. Connected to the piston is the piston rod C,

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which passes through the gland, or stuffing box T. This gland is for
the purpose of holding the packing which prevents the escape of
steam around the piston rod. The end of the rod, or crosshead D
slides back and forth in the crosshead guides Q Q. To the crosshead
is attached the connecting rod E, by means of the wristpin V. In
the lower end of the connecting rod is the crankpin F .

In steam automobile engines the flywheels P P are usually not
needed and are consequently omitted. The rim of the gear wheel,
when the engine is geared directly to the rear axle, has a slight fly-
wheel action.

SLIDE VALVE

The leading mechanical elements of the steam engine have been
briefly described. It remains now to show the precise manner in
which the steam is used.

Elementary Slide Valve. Fig. 10 represents an elementary slide
valve. In order to indicate the movements of the crankpin and the
valve eccentric on one drawing, the crankshaft center is located at

A . B represents the

Fig. 10. Elementary Slide Valve — Valve in Mid-Position

Fig. 11. Elementary Slide Valve — Inlet and Exhaust Ports
Partly Uncovered

Fig. J 2. Elementary Slide Valve — Inlet and -Exhaust Porta
Fully Opened — Piston in Mid-Position

crankpin center with
the piston C at the
inner end of its
stroke. The larger
dotted circle is the
crankpin circle, and
the small circle is that
in which the center
D of the eccentric
moves. With the
crankpin traveling as
the arrow shows, the
valve is in mid-posi-
tion when the piston
starts to move, and
the first effect of its
movement is to un-
cover the steam port
E, at the same time
establishing com-

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STEAM AUT0M0BILE3

munication between port E' and exhaust port-F, Fig. 11. At half-
piston stroke the ports are wide open and the valve starts to return,
Fig. 12. When the crankpin reaches the outer dead center G the
ports are again closed.

Use of Steam Cut-Off. A steam engine with valve arranged as
above would take steam through the entire stroke, and would exhaust
at boiler pressure. It would develop the maximum power of which it
was capable at that pressure, but no use would have been made of

fO LBS.

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Fi«. 13. Theoretical Indicator Diagram for One-Half Cut-Off

the expansion force of the steam. For this reason, all practical steam
engines are made to admit steam only for the first portion of the
stroke, that is, about one-half stroke or less, the remainder of the
stroke being devoted to expansion. In Fig. 13, suppose A represents
the position of a piston moving from left to right. The horizontal
distance B C represents the stroke, and vertical distances represent
steam pressures. D E is the line of zero pressure, and F C that of
atmospheric pressure. Suppose steam is admitted at 50 pounds gage
pressure during the first half of the stroke from G to //; the steam
port then closes and the steam expands with diminishing pressure
along the curve H I. Since work is the product of force into distance
traveled, it follows that for each fraction, such as B J of the piston
travel, the included area BG KJ will represent the work done
during that portion of the stroke, and the area of the entire card
BG H I C will represent the work done during the whole stroke.

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Fig. 14. Theoretical Indicator Diagram for One-
Quarter Cut-Off

In the case under consideration, the area of the whole diagram is
84.4 per cent of that which would have been produced if the steam
had entered during the entire stroke, yet only half as much steam
is used.

Indicator Diagrams. A diagram such as Fig. 13 is called the
"indicator diagram" or "indicator card", and is employed to study

the internal action of
the engine. The expan-
sion curve of steam fol-
lows Boyle's Law with
sufficient closeness for
practical purposes. Fig.
14 is similar to Fig. 13
except that the steam is cut off at one-quarter stroke, point H.
In the foregoing, no mention has been made of the contents of
the steam passages between the slide valve and the cylinder, or of the
clearance volume between the piston and the cylinder head when the
crank is on dead center. These clearance spaces cannot wholly be
avoided, but it is desirable to reduce them as much as possible. It
is customary in indicator cards to represent the clearance space
by an area to the left of the actual indicator card. This area is
F LG B in Fig. 13 and Fig. 14. Its volume averages about 5 per
cent of the volume swept by the piston. Owing to the necessity

of taking the steam in
the clearance space into
account, the actual steam
consumption in Fig. 14 is
a trifle more than half
that in Fig. 13.

Effect of Compres-
sion on Indicator Card.
The objectionable influ-
ence of the clearance
may be neutralized by
closing the exhaust port
before the piston has finished its return stroke, thereby trapping
the remaining steam at atmospheric pressure and compressing it to
boiler pressure. If this is done, none of the entering steam is wasted

Fig. 15. Actual Indicator Card, Showing Compression

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merely in filling the clearance space. Fig. 15 shows the effect of
compression on an actual indicator card. It is not carried to boiler
pressure, but only to point A.

Another reason for using compression is to cushion the recipro-
cating parts at the end of their stroke and prevent the shock which
may otherwise occur on suddenly admitting live steam.

Effect of High Pressure and Early Cut-Off. As Fig. 14 shows,
no great advantage is gained when working with steam at 50 pounds

by cutting off earlier
than one-third stroke. If
higher pressure is used,
however, the cut-off can
be considerably short-
ened. Fig 16 is a theo-
retical indicator diagram
for 200 pounds gage
pressure (214.7 absolute).
The clearance is 5 per
cent of the piston dis-
placement, and cut-off
occurs at one-tenth
stroke. The weight of
steam per stroke is about
the same as in Fig. 14,
but the work done by the
higher pressure is nearly two-thirds greater. This shows strikingly
the economic advantage of using high pressure, provided the cut-
off is shortened to correspond.

Effect of Adding Steam Lap, To produce a short cut-off, what
is known as outside lap or steam lap is added to the edges of the slide
valve A A, Fig. 17. To produce
compression inside exhaust lap
B B is also added. Figs. 18 and 19
show how the valve mechanism
is affected by these changes. In
Fig. 18 the piston is about to begin its stroke, but the valve is no
longer in mid-position. Instead, the eccentric has had to be ad-
vanced through an angle, known as the "angle of advance", in order

Fig. 16. Theoretical Indicator Card for One-Tenth
Cut-Off

Fig. 17

Section of Slide Valve, Showing
Steam and Exhaust Laps

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Fig. 18.

Elementary Slide Valve, Showing Effect of
Adding Laps

Fig. 19. Elementary Slide Valve, Showing Adjustment
of Lead

to open the port as the piston starts to move. The necessary travel
is also increased in order to accomplish the idle movement when all
ports are closed. As the diagrams show, the valve reaches the end

of its movement, re-
turns, and closes the
steam port while the
piston is in the first
quarter of its move-
ment. It then con-
tinues to move, but
with only the exhaust
open.

It is customary,
as Fig. 19 shows, to
open the steam port
a trifle before the
piston begins its
stroke in order to
avoid wire drawing of the steam before the port goes fairly open. If
this were not done, there would be an appreciable drop in pressure
at the beginning of the stroke. The amount of this premature open-
ing of the valve is called its "lead".

SUPERHEATED STEAM AND COMPOUND EXPANSION

Superheating to Avoid Cylinder Condensation. When steam
expands its temperature drops by reason of expansion, causing the
cylinder walls to assume an average temperature which slightly
increases from contact with the hot steam and slightly diminishes at
the end of every stroke. The hot entering steam condenses on the
walls, and re-evaporates near the end of the stroke. This is very
undesirable, and is avoided by superheating the steam sufficiently
to compensate for the initial loss of heat to the walls. In addition,
heat loss by radiation is minimized by lagging the cylinder w r alls and
heads with asbestos, magnesia, or other non-conducting coverings.

When steam is used at pressures above 100 pounds, compound
engines are preferable, although not always used.

Compound Engines. In a compound engine the work done by
expansion is divided as nearly equal as practicable between two

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cylinders, called respectively the high-pressure and the low-pressure
cylinder. The high-pressure cylinder is the smaller in diameter,
and it exhausts into the low-pressure cylinder instead of into the
atmosphere. In the diagram, Fig. 20, showing the elements of
a compound engine, the
steam is being transferred
from the high-pressure
cylinder to the low-pres-
sure cylinder. The steam
expands by reason of the
difference in the areas of
the two pistons.

A compound engine
may be considered as
though the steam were
expanded wholly in the
low-pressure cylinder, and
the indicator diagrams of
the two cylinders may be
combined to show the total
work done, by shortening
the horizontal distances of
the high-pressure card in proportion to its smaller piston area.
Comparison of Indicator Diagrams for Stationary and Automobile
Engines. Fig. 21 is a combined diagram from the high- and low-
pressure cylinders of a stationary compound engine. Both cards are
drawn to the same scale as regards stroke, but the low-pressure card

reads from right to left.
F is the point of admis-
sion to the high-pressure
cylinder. The slight peak
at A is due to the inertia
of the in-rushing steam.
At B the admission valve
closes. At C the steam is
released and goes into
the receiver between the

Indicator Diagram of a Stationary Compound i* i t\ r< • j_i

steam Engine cylinders. D L is the

Fig. 20. Elements of a Compound Steam Engine

Fig. 21.

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exhaust line, and E F the compression line. From DtoE steam passes
from the high- to the low-pressure cylinder, the difference between
the two lines being due to frictional resistance of the passages. At G
the exhaust valve opens. HI is the compression line of the low-
pressure cylinder.

Use of Condensers. In the foregoing paragraphs steam is
supposed to be exhausted at atmospheric pressure. In other words,
the steam in the working end of the cylinder must overcome a back
pressure of 14.7 pounds per square inch in the exhaust end. If the
exhaust steam were discharged into a closed vessel and condensed,
a vacuum would be formed containing only water vapor at a pressure

Fig. 22. Stanley Radiator Fig. 23. Doble Radiator

proportionate to its temperature. This would mean the addition of
5, 10, or even 12 pounds to the height of the indicator card without
having to increase the heat units put into the steam. To do this
requires considerable apparatus — condenser, vacuum pump, etc., all
of which it has been found inadvisable to install on an automobile.

Condensers on steam cars are not for the purpose of increasing
the total expansion by dropping below atmospheric pressure, but to
condense the water at atmospheric pressure so as to be able to use it
again and avoid having to fill the water tank so often.

As shown in Figs. 22 and 23, both the Stanley and the Doble
use condensers of the same general construction and appearance as

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STEAM AUTOMOBILES 23

the radiators used on the ordinary gasoline car. The exhaust steam
from the engine enters at the top of the radiator and is forced down-
ward by the steam which is following. As it passes down the radi-
ator, the air going through the spaces between the water passages
cools it, until, by the time it reaches the bottom, it has been con-
densed into water.

VALVE GEARS

Throttling and Reversing. Steam engines are regulated partly
by the cut-off and partly by throttling. As has been pointed out
above, it is impracticable to use a cut-off so short as to expand the
steam to, or below, exhaust pressure. Beyond this point reduction
of power must be had by throttling the steam on its way to the engine.
The shortening of the cut-off, and the complete throwing over of the
valve timing to the other side of the dead center to reverse
the engine, may be accomplished by shifting the angular position
of the eccentric on the crankshaft or by the use of one of several
valve gears or linkages.

Types of Gears. Up to the last few years the most common
gear was the "Stephenson Link", developed by Robert Stephenson
and Company, in 1842. In locomotive work the Stephenson gear
has been largely displaced by the Walschaert gear. Practically all
the earlier steam automobiles used the Stephenson, but later some
changed to the "Joy Gear", which is one of a number of radial gears
employing linkages without the use of eccentrics.

Stephenson Link. The Stephenson link is shown in Fig. 24. It
consists of two eccentrics A on the crankshaft — one for the for-
ward motion and the other for the reverse. The two eccentric rods
are pinned to the link B, in which there is a curved slot. In the
slot is carried the block C, which is a sliding fit and is pinned to
the valve stem.

By means of the hanger rod D and the reverse lever arm E f
the link is moved up and down, so that the slide is in different posi-
tions from the center of the slot. When the block is on one side of the
link center it partakes of the motion of one of the eccentrics, and
when on the other side of the motion of the other eccentric. Thus
the valve timing is changed from the forward running position to the
reverse by changing the position of the block in the curved slot.

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It is a feature of the Stephenson link motion that by rocking
the link toward (but not to) its mid-position the valve travel and
cut-off are shortened, and this feature is utilized to improve economy .
At the same time the lead is increased, that is, steam is admitted
before the piston begins its new stroke. This is not a disadvantage

Fig. 24. Stephenson Link Motion Used on Stanley Steam Cars

at high speeds, as the fresh steam has a cushion effect on the recip-
rocating parts. At low speeds, however, the engine runs jerkily, and
consequently the cut-off is shortened only at medium to high speeds.
Joy Gear. The Joy gear is a well known English development,
which is used on a number of steam automobiles. Its operation may

Fig. 25. Diagram of Joy Valve-Gear Mechanism

be understood by referring to Fig. 25. A link is pinned at one end to
the engine at H and at the other end to a link, which in turn is pinned
to the connecting rod at C. To this second link is pinned the link

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STEAM AUTOMOBILES 25

D E, to the upper end of which is attached the rod E G, which moves
the valve. At A on D E is pivoted the block A, which slides in the
slotted guide, the guide being slightly concave on the side toward
the valve. This guide is pinned to the engine frame at its center
point P. In the position of the guide, as shown, the valve is in full
gear for forward running, but if the guide is swung about the point P,
by means of a connection at F, until it is in the position B F, the
engine will then be in full reverse.

As with the Stephenson, the moving of the Joy toward the half-
way point shortens the cut-off. This gear has an advantage over the
Stephenson in that the lead is not increased and the distribution of
steam to the two ends of the cylinder on short cut-off is more nearly
equal. The Joy gear also gives a rapid opening and closing to the
valve.

ENGINE TYPES AND DETAILS

Although makers have their individual preferences in engine
types as regards the placing of the cylinders, compounding, and
other features, the practice of using two cylinders has become almost
universal.

Stanley. An example of the two-cylinder type is the Stanley
engine, which, in the present models, is made in three sizes of the
following bore and stroke: 3£ by 4 \, 4 by 5, and 4| by 6£ inches.
This engine is geared directly to the rear axle by a spur gear mounted
on the crankshaft, as shown in Fig. 26, and the frame rods are
attached radially from the axle housing. The cylinder end is attached
to the frame of the car. The rear-axle gear ratio in the small light
runabout model is 30 to 56, and in the heavy delivery car is 40 to 80.
With a gear ratio of 40 to 60 in one of the touring cars the engine
turns over at 447 r.p.m. when the car is running 30 miles per hour.

Both cylinders take high-pressure steam at both ends, the engine
being of the double-acting, simple type. The steam chest, Fig. 27,
lies between the two cylinders, with the D-slide valves driven by the
eccentrics lying next to the drive-shaft gear. In Fig. 26 is shown
the Stephenson link by which the cut-off is hooked up and the reversing
of the engine accomplished. This valve gear has been described in
detail on page 23. The cross shaft, working the link, and the hook, for
holding it in the normal position, are shown just to the left of A.

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26 STEAM AUTOMOBILES

The hooking up is done by the left pedal, which can be released by a

pedal beside it called the clutch pedal.

Roller and ball bearings are used extensively in the Stanley

motor. The crosshead bears on a plain crosshead guide, and the

connecting-rod and eccentric-
strap bearings are of the ball
type. The counterweights are
also shown in Fig. 26.

Lubrication of the outside
parts is effected by enclosing the
gears, crankshaft, and other parts
in a sheet-metal case, which is
kept about half full of moderately
thin mineral oil. The lubrication
of the cylinder walls is accom-
plished by feeding the oil into the
steam line, and the special super-
heated steam-cylinder oil recom-
mended is given fully in a later
section.

The Stanley power pumps
for water, fuel, and oil, shown in

Fig. 20. Stanley Two-Cylinder Steam Engine, Fig. 46, are driven from the rear

Showing Link Motion and Balanced Shaft

axle.
Doble. The Doble engine, shown in full length section in Fig.
28, is made up of two cylinders of the same size. It is of the simple-
expansion double-acting type, and the interesting feature is that the

uni-flow principle is employed. The
cylinder bore is 5 inches and the
stroke is 4 inches.

On top of the cylinders are the
valve chests. Each valve is made
up in two pieces so that it may lift
when the compression pressure ex-
ceeds the steam pressure, as some-
times happens in slow running. This

Fig. 27. Cylinder Construction of Stanley Construction alk)WS the USe of high
Steam Kngino, Showing Steam . 1 • i • i • i ^ u.i_

chest in center compression, w r hich is desired at the

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STEAM AUTOMOBILES 27

higher speeds. The gear used to control the valve motion is a
modification and simplification of the Joy gear, Fig. 25. In the

Doble gear the connecting
and anchor links are done
away with, and a straight
rocker guide is employed.
In starting, the cut-off is
five-eighths stroke, and this
same position is used for
heavy pulling. For ordinary
running, one-fifth stroke cut- .
off is used, while for econ-
omy and high speed it is
•| reduced to one-eighth
§ stroke.
g i By the uni-flow prin-

j|5 ciple is meant that the
3 | steam moves in but one
2 J direction within the cylin-
g | der. It enters through the
I .g inlet passage at the extreme
. c5 end of the cylinder, expands
^ | against the piston head, and
fo 2, passes out of the exhaust
J ports, which are uncovered
§ by the piston a little before
it reaches the end of the
stroke. It is claimed for
this system that the thermal
conditions are so good that
the use of superheated
steam, with its attendant
troubles, is unnecessary.

Aluminum is employed
for the crankcase, with large
cover plates, top and bot-
tom, for easy access to the
moving parts. The accessibility of the valve gear is very well

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28 STEAM AUTOMOBILES

shown in Fig. 29. The case, which has its cover removed, con-
tains all the moving parts of the engine with the exception of the
valves and pistons; and, since the case and the axle tubes, which
are bolted to it, are oil-tight, all these parts are "kept in a bath of

Fig. 30. Piston and Crosshead Guide of Doble Engine

oil. This oil keeps comparatively cool and as there is no combus-
tion, it does not deteriorate as in the gasoline car.

A special design of long cast-iron gland is used for the piston
rod at the cylinder, and there is a stuffing box where the rod passes
into the crankcase. The crosshead guide is part of a cylinder, as

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STEAM AUTOMOBILES 29

slown in Fig. 30, giving a large bearing surface. Annular roller
bearings are used for the big end of the connecting rod, for the
crankshaft, and for the differen-
cial. Hardened steel, running in
hardened steel bushings, is used

for all the other bearings.

Being geared at practically a

1 to 1 ratio to the axle shafts, the

engine always runs at compara-
tively slow speed. A 47-tooth

pinion is carried on the engine

crankshaft and to this is fastened

the counterbalance. This gear

. . , p , Fig. 31. Top View of National Power Plant

meshes With One OI 49 teeth On bfor London Steam Omnibuses

.i j./« ,. i .j mi ].* Courtesy of Society of Automobile Engineers,

the differential spider. Ine dif- New Yorkaty

Fig. 32. Separate Engine and Dynamo for Lighting National Busses
Courtesy of Society of Automobile Engineers, New York City

ferential is of the three-pinion bevel-gear type. Meshing with the
axle gear is an idler, and then a gear on the electric generator, which
furnishes current for the combustion system and the lights.

National. In the National steam omnibuses of London, Eng-
land, the engines are placed under the floor boards, Fig. 31, and,

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unlike any of the American engines, the two cylinders lie across the
chassis. The drive is taken by a shaft to worm gearing at the rear
axle. These engines have a Joy gear, and the pumps for the water
and kerosene are driven from a cross shaft, which in turn is driven
by a worm gear off the extension of the crankshaft, as is shown in the
illustration. An interesting feature of the National chassis is the use
of an entirely separate steam engine for driving the electric-lighting
generator, which supplies the large number of lights used inside the
busses. This auxiliary engine is shown in Fig. 32.

From what has been said it must not be supposed that all auto-
mobile steam engines use two-cylinder engines with either D or piston
valves. The Pearson-Cox steam truck of England has a three-
cylinder vertical engine with poppet valves in chambers at each side
of the cylinders, and the whole engine looks very much like a vertical
poppet-valve gasoline motor.

A number of very heavy English trucks, or "lorries" as they call
them, are driven by steam, and are very popular in England. These
carry from 3 to 10 tons, and the boilers and parts of some of them
are very large.

FUELS AND BURNERS

Gasoline and Kerosene as Fuels. Energy for driving steam
engines is derived, of course, from the fuel burning and forming
steam from the water, the steam in turn doing mechanical work by
its expansion in the engine. In an automobile it is of prime^impor-
tance that the fuel be as easily handled, carried, and purchased as
possible. Of the commercial fuels, gasoline and kerosene come the
nearest to these ideals and are, therefore, the most jypular. Kero-
sene is less expensive than gasoline, but does not vaporize at as low a
temperature while, as a rule burners are specially designed for kero-
sene, many modern burners will handle either of these fuels or a
mixture of them.

To burn either of these fuels the vapor must be mixed with air,
which supplies the necessary oxygen for combustion. Either of these
vapors, if mixed with the right amount of air, is highly inflammable
and explosive, and therefore, care must be taken in storing and
in filling the fuel tank, not to have open lights about — not even
lighted cigars.

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Burner Principles. Bunsen Burner. The purpose of the burner
is^first to vaporize t hejiguid fuel by heating it and then to mix it
with enough air to produce the hottest possible flame under the
boiler. In principle the burner is the same as the ordinary Bunsen
burner, Fig, 33, in which the gas passes under moderate pressure
through the small opening b. In going up the tube a it draws
in a certain amount of air through the openings o, the fuel gas and
air becoming well mixed in the tube before reaching the flame. In
case either too much or too little air is mixed with the gas, the flame
will run back through the tube
a, and will burn at o. This is
called "popping back", and not
only takes away the effect of the
flame but will ruin the burner if
allowed to continue in operation
in this way.

Modifications for Automobile
Work. In automobile work the
burner is somewhat modified in
order to a ct ove r a large area and
to give a flame of more intense
Keat. Forjthe purpose of feeding
more gas, and_to mix, it- more
quickly with the air, the fuel i§
fed under considerable pressure.

The correct mixture of air
and fuel gas gives a blue flame,,
just slightly tinged with orange at
the top, and burning rather close
fo IHe burner. If too much air is given the mixture, the flame will start
a considerable distance above the burner and will be very blue. The
excess air tends to cool the flame. Too little air is equally bad, for
the combustion will then be incomplete and, since gasoline and
kerosene are hydrocarbons, soot will be deposited on the surfaces
above the flame. Such a flame is indicated by a yellow color. As in
the ordinary Bunsen burner, poor mixtures are apt to pop back.
When this happens the operator must turn off the burner and relight
it. The popping back is indicated by a roaring sound.

Fig. 33. Typical Bunsen Burner

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32 STEAM AUTOMOBILES

Pilot Light. As the demand for steam is not constant in an
automobile, it is desirable to have the main burner come on and off
automatically. In order to light the main burner whenever it may
come on, a small light is kept burning continuously while the car is
in use, whether running or standing still. It is even the practice of
some owners to keep this pilot light, as it is called, lighted over night.
Besides relighting the main burner when the car is running, the pilot
is lighted first when firing up a cold boiler. The burning of the pilot
serves to heat the vaporizer of the main burner as well as to light the
main fire. The handling of the pilot in firing up will be taken up later.
Due to its easier vaporization, gasoline is always used for the
pilot-light fuel even when kerosene is used for the main burner. It
is also quite general to have the two fuel systems separate, although
both may be using gasoline. In starting up a cold system the pilot
vaporizer must be heated by some outside means. This is done in

several ways: one is to use
a separate gasoline torch;
another is to use an acety-
lene torch instead of a gas-
oline torch; and a third
method is to light a little
pool of gasoline below the
vaporizer, similar to the
method used in many gas-
oline cook stoves and plumb-
ers' torches.

Types of Burners. Dif-

Fig. 34. Stanley Burner, Showing Vaporiser and ferent makers, of COUrse

Courtesy of Sla^^J^cTrria^ Company, USe SOmewhat different COn-

Ncvton, Massachusetts structions for their burners,

but in all cases the fuel gas is vaporized by heat and mixecHn a burner
of the Bunsen type. As a fair example of all the burners, that of
the Stanley will be described in detail, while short descriptions will
also be given of other makes.

Stanley. Either gasoline, kerosene, or a mixture of the two can
be burned in the Stanley main burner. The burner, Fig. 34, consists
of a corrugated casting with a large number of slots cut across the
peaks of each parallel corrugation. Vaporization of the fuel takes

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place in the two coiled tubes A A which lie directly over the fire.
From the vaporizing tubes the gas flows at high velocity through the
nozzles B B into the mixing tubes C C drawing with it the air
necessary for good combustion. The mixing tubes lead under the
burner, and combustible gas issues through the fine slots, where it
burns with an intensely hot blue flame tipped with orange. No air
currents are present to blow or cool the flame, for the burner casting
excludes all air except that drawn in and mixed with the gas through
the tubes C C. To adjust the amount of air to give the correct color
to the flame, bend the nozzles closer to the opening of the mixing
tube for less air, and vice versa.

Between the two main-burner vaporizer tubes is located the
pilot light, which is a small independent casting. The pilot burns
gasoline, supplied from a separate tank, irrespective of whether the
main burner uses gasoline or kerosene. Due to the position of the
pilot, it keeps the main-burner vaporizer warm when the main burner
is shut off by either the automatic or hand valve controlling it. When
the main burner is turned on, the pilot flame ignites the gas. Since
the pilot is independent of the main-burner valves, it remains lighted
until turned off by its own hand-operated valve. The heat from the
pilot is sufficient to hold steam in the boiler for several hours after the
car is stopped and the main burner shut off.

In starting up the pilot of the Stanley when cold, an acetylene
torch is played on the pilot vaporizer to vaporize the first gasoline,
after which the heat from the pilot light itself keeps the pilot vapor-
izer warm. The acetylene is carried in a "Prest-O-Lite" tank and
turned on by a valve at the tank. The torch lights by simply apply-
ing a match, and should be played on the pilot vaporizer until it is
sizzling hot, which takes between 15 and 30 seconds. The torch is
then moved so that the flame enters the peek-hole, lighting the pilot,
after which the torch is played upon the upper part of the vaporizer
for 15 to 30 seconds, until the main burner nozzles are sizzling hot.

After closing the acetylene-tank valve the main-burner valve is
opened and closed quickly several times until the gas from the main
nozzles is dry. It is then left open, being lighted by the pilot flame.
The pilot nozzle is provided with a wire which is filed off on one side
to allow the passage of the gas. If the pilot light does not seem to
burn strongly, it can be cleaned while burning by turning the outside

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screw back and forth with a screwdriver. If this does not suffice,
the wire should be taken out and cleaned; it is good practice to do
this every day before firing up. The color of the flame can be adjusted
by bending the nozzle tube to bring the nozzle in or out from the
mixing tube, the same as is done in adjusting the main burner.

In the older models of Stanley cars, which used only gasoline as
the main-burner fuel, the pilot fuel system was a branch of the main
system, and the pilot vaporizer was heated by a gasoline torch.

Fig. 35. Section through Combustion Chamber and Boiler of Doble Car
Courtesy of General Engineering Company, Detroit, Michigan

Doble. Very radical departures from the long-established Bun-
sen type of burner have been made in the combustion system on the
new Doble car. The fuel is ignited by electricity and there is no
pilot light. Kerosene is used for both starting and running and is
fed from the main fuel tank to a float chamber by an air pressure of
three pounds per square inch. From the float chamber, which is of
the standard gasoline-carbureter type, the fuel passes through a spray
nozzle, which is located in the throat of a Venturi tube leading to
the combustion chamber.

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Air for the support of the combustion of the fuel is drawn
through the radiator by means of a multiple-vane fan driven by a
small electric motor. It passes the jet with sufficient velocity to
draw out the fuel and atomize it. Owing to the enlarging of the
passage directly beyond the throat, the velocity is decreased in order
to give time for the complete
combustion of the gas by the
electric spark, which takes place
at this point.

The combustion chamber,
Fig. 35, is completely closed and
lined with a highly refractory
material. As soon as the com-
bust ion has bee n s tarted ^ the
electric spark is automatically

.--- : — . - .' . « ,, Fig. 36. Ofeldt Blue Flame Kerosene Burner

shut oft, and the burning ol the CourusyofF.w.ofeidt and Sons,

.— - - -— - .. . . Nyack-on-the-Hudson, New York

gas is continuous untiLJt. is

stopped by the action of the automatic steam control, as described
later. The lining of the chamber not only has the property of
resisting high heats, but it holds and gives back the heat so as to
assist in completely burning the gases. The combustion chamber
is also well illustrated in Fig. 41, page 40.

Ofeldt. The Ofeldt burner, Fig. 36, is designed especially for
the use of kerosene as a fuel. Forming the foundation of the burner is

Fig. 37. Kerosene Burner, Used on National Busses with Starter
Courtesy of Society of Automobile Engineers, New York City

a galvanized iron pan, lined around the sides with millboard asbestos.
In t he bottom o f the pan are drilled rows of small holes. Since these
holes are in straight lines under the burner pieces, and of equal size,
they admit even amounts of air throughout the lengths of the burner
pieces.

Cast iron is used for the burner pieces, which radiate from a

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36 STEAM AUTOMOBILES

central gas-distributing chamber, into which they are screwed. The
gas flows through fine slots cut in the burner pieces. Surrounding the
mixing tube is the main vaporizer A, which passes through the outside
of the pan, ending in the nozzle B at the opening of the mixing tube.
The mixing tube is a part of the central gas-distributing chamber.
Attached below the burner pan is the pilot D, where its flame
heats both the main and the pilot vaporizers and the mixing tube.
By means of a hand valve the pilot flame can be adjusted to keep up

steam when the main burner
is out, or it can be turned
down so as to keep only the
main vaporizer warm.

A comparative ly low
pressure_-Js_used on the~
Of eldt system, the fuel being
kept under about 60 pounds
per square jnch.

National. Kerosene is
used as the fuel in the
National busses. These
burners are quite different
in appearance from those
described above, as is shown

Fig. 38. Stanley.Fire-Tube Boiler in Fig. 37.

AUTOMOBILE BOILERS

Classification. In stationary steam-power plants there are two
distinct classes of boilers, the fire-tube and the water-tube. These
two types are also used in automobile work, together with a third
type, the flash boiler, which is a development of the wat er-tube type.

Fire-Tube Boilers. In principle the fire-tube boiler is like a big
tea-kettle filled with vertical tubes, which run from the bottom to the
top for the purpose of carrying up- the flame and hot gases. This
construction gives a very large surface on one side of which are water
and steam and on the other flame and hot gases.

Stanley. One of the simplest of the fire-tube boilers is the
Stanley, Fig. 38. This is made up of a pressed-steel shell, which
includes the lower head, the upper head being a separate piece.

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Between these two heads run a large number of tubes of %i inch
outside diameter, which are expanded into the heads by a taper
expanding tool. Stanley boilers are made in three sizes, 20, 23, and
26 inches in diameter and 14 and 16 inches in height, respectively.
The number of tubes is 550, 751, and 999, giving 77, 104, and 158
square feet of heating surfaces. To keep down the radiation losses,
the boiler shell is lagged with asbestos, and the strength of the shell
is greatly increased by winding it with steel piano wire.

To keep a reserve of steam, and to have the steam free from

particles of water, the boiler is kept only about two-thirds full of

water, the upper space being filled with steam. To fur ther^insure

d ry steam_at the engine the steam is led by a pipe from the top of the

'"Boiler d own t o a superheating coil directly over the burner.

Fusible Plug. As a warning against too low water the side of
the boiler is provided with a fusible plug, held in a fusible-plug tnbe
which, in turn, screws into a steel fitting. The elbows on this fitting
are made on a taper and are driven into two short tubes in the boiler.
As long as the water level is above these tubes the circulation prevents
the plug from melting. If the water gets below the plug and about
3 inches from the bottom of the boiler, the plug will melt and the
noise of the escaping steam will warn the operator of the danger* — not
danger of an explosion of the boiler, but danger of doing the boiler
damage by heating it without water. There are other means by
which the operator may know that the water is getting low before it
gets low enough to blow out the plug, and these will be taken up in
detail later, together with the causes of unexpected low water and
other points.

The fusible plug may melt out, not only from low water but also
because of dirt or something retarding the circulation of water around
the tubes or fittings. The blowing off of the steam will usually remove
the obstruction. If the escaping steam is dry, it is a sign that the
melting has been caused by low water, but if it is wet the trouble is due
to faulty circulation. It is good practice to replace the fusible plug
once every two or three weeks, doing this when the boiler is cold.

Since the addition of the condenser to the Stanley in 1915, these
boilers have been made without the fusible plugs. Among other
improvements in these boilers is the brazing, or welding, of the tubes
in the lower heads. This is to prevent any trouble from oil, which

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38 STEAM AUTOMOBILES

might be carried over into the condensing system. Before the boilers
are turned out from the factory, they are tested by a water pressure
of from 1500 to 1800 pounds jjei 4 square inch.

Water-Tube Boilers. Water-tube boilers also are made up of
tubes, but in this case the tubes carry the water and steam inside and
the fire and hot gases pass over the tubes. The metal hood over this
type of boiler carries no pressure, but merely serves to keep in and
direct the hot gases. In stationary practice the tubes are often
straight or only slightly bent, but to economize space the automobile

boiler has the tubes^coiled to give the
most surface to the fire in the least
possible space.

Ofeldt. The Ofeldt safety water-
tube boiler, Fig. 39, is built about
a central standpipe of 5 inches or
more in diameter, with a bottom of
^-inch metal welded in. Threaded
into the upper end of the standpipe
is a steel cap with three arms, to the
ends of which the sheet-metal hood,
or cover, is fastened.

The object of the standpipe is to
hold a reserve of water at the bottom
Fig. 39. ofeldt Safety Water-Tube and of steam at the top, and to dis-
tribute the water to the coils. In
the coils and standpipe the reserve of water varies from 3 gallons in
the small sizes to 8 gallons in the 24-inch size.

Water is fed to the bottom of the standpipe, from where it flows
into the coils. As it passes up the coils it turns into steam. A
pipe from the center of the standpipe carries the steam down to
the superheater, which lies under the boiler directly over the burner, as
shown in Fig. 39. From the superheater the steam is carried by the sec-
ond straight pipe back to the top of the boiler and then to the engine.
These boilers are supposed to supply steam at 250 pounds pres-
sure but are tested up to 1000 pounds per square inch.

Doble. Almost as great a departure from ordinary practice has
been made in the Doble boiler as in the combustion system previously
described. The generator is of the water-tube type, with the tubes

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arranged in rows, which are really separate sections, Fig. 40. There
are 28 of these sections in the generator part of the boiler. The
tubes are made from seamless drawn-steel tubing of about §-inch
diameter and are swaged down to a diameter of about f inch at the
ends. These ends are welded into the top and bottom headers,
thus making each section a continuous piece of steel.

Besides the 28 sections of tubes in the generator portion, there
are 8 more sections in the economizer or feed-water heater. The

Fig. 40. One Section of Doble Boiler
Courtesy of General Engineering Company, Detroit, Michigan

arrangement of all these sections is clearly shown in Fig. 41, the view
being cut across each of the 36 sections, similar to Fig. 40. The
picture does not show all the details but has been arranged to give an
idea of the general layout and the direction of flow of the hot gases and
of the water and steam. The boiler sections are completely covered
over, except at the bottom, by a f-inch wall of heat-resisting and
insulating Kieselguhr material. Over this is a planished iron jacket.
All of the sections are connected together by headers, which run
along the sides of the boiler. One of the features of the construction
is that if anything should go wrong with a section of tubes, it can be

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very easily cut out of operation by means of the side headers, until
such time as it is convenient to replace the section.

In Fig. 41, the direction of flow of the hot gases of combustion
is shown by the heavy arrows, while the flow of the water and steam
is indicated by the small arrows. From the combustion chamber at
the bottom of the boiler, the gases pass upward and then over the top
of the fire wall between the generator proper and the economizer.
Here they turn and pass downward in order to escape through the

Fig. 41. Section through Doblc HoiWr, Showing Combustion Below and Economizer
Section at Ki^ht

exhaust at the bottom. It should be noted that the power-driven
feed pump forces the water in an upward direction in the economizer
tubes, exactly opposite to that of the gas flow outside of the tubes.
From the top headers of the economizer sections, the water over-
flows through a manifold to the lower headers of the generator
sections. An automatic valve controls the feed water, so that the
water in the boiler, under normal conditions, stands about half-way to
the top. On the road, the usual pressure is around GOO pounds per
square inch, which is maintained by an automatic valve controlling

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the fuel supply. Each section of the boiler is tested to a water pres-
sure of 5000 pounds per square inch. The actual bursting pressure
is said to be over 8000 pounds. As a precaution against any danger,
however, a safety valve is attached to the boiler.

Flash Boilers. Flash boilers differ from the fire- or water-tube
types, both of which have a reserve of steam, in that the steam is
generated only in the quantity jemanded each moment by the
wigine. The se hoilfii^ consist of a continuous metal tube in one or
more coils lying over the burn er. As the water from the reservoir
passes along the tube it gets hotter and hotter until at some point
in the t ube it Burst s into steam. During the rest of its travel the
steana js superhea ted.

A s practically no steam is kept in reserve^ the capacity of the
bo iler and burner mustjj gjgreat enough to supply at once the maxi-
mum demand for h ill climbing. The relations of water and fire must
be nicely b alanced at all tim es to prevent top much superheat on one
ha nd and wet steam on thej>ther.

Safetyjigainst a dangerous explosion is the leading argument for
the flash type of boiler. Since there is no reserve of steam or hot
water under^presstire, there is no large amount of energy to be
liberated in case of a rupture of any part of the boiler.

Serpollet System. In the early days of steam automobiles a
Frenchman named Serpollet reduced the amount of water in a boiler
to an extremely small amount. To give the maximum of heating-
surface area together with a minimum of cross-sectional area, the
tubes were made a U-section instead of circular; this type, however,
was abandoned later.

With the Serpollet system the fuel and water were fed simul-
taneously, one lever varying the strokes of both pumps. To avoid
trouble from extreme superheat, single-acting pistons and poppet
valves were employed. The valve cut-off was variable and worked in
conjunction with the fuel and water supplies. Since there was no
reserve of energy to the system, it took a great deal of skill to handle
it smoothly, especially in hilly country. *

White. A great improvement over the Serpollet system was the
flash generator of the White Company. Although the White steam
cars were discontinued in 1911, they were the leading example of the
flash system in this country.

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42 STEAM AUTOMOBILES

In the White j^ener^tor Jtheig was a suff icie nt sup ply of wRterto
serve as a reserve in caseso f sudden demand . Referring to Fig. 42,
it will be noted that the boiler was made up of several rows of tube *,
each coiled in a horizontal pKp^, »"d each connected +*» t.b^J^
below by a tube which first passes to the top of th e boile r. Unlike
the ordinary fire-tube or water-tube boilers, the wa ter entered th e
White boiler at the top, through the pipe 128. The upper coil was b
the coolest portion of the gases from the burner. After passing
through the top coil, the water flowed through the tube at the end of
the coil, being carried up and over the top of the boiler and then
down to the second coil, and so on down from coil to coil. Bei ng
nearer the burner, each coil was hotter than_ihe_J>ne above, and,

Fig. 42. Generator, Burner, and Fuel Connections Formerly Used on
White Steam Cars

since the vertical pipes at the ends of the coils kept the hot water
from circulating back to the coil above, there was some point in the
lower coils where the water burst into steam. The_steam J>ecajue
superheated during the remainder of its travel through the coils ana
left the boiler by the pipe 129.

These principles of construction were held to in all the White
steam cars from 1904 to 1911 inclusive. Because of the strength of
the small-diameter tubes and the small amounts of steam and water

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STEAM AUTOMOBILES 43

the boiler at any one time, it was possible to carry a working
p>x"cssure in these generators of 600 pounds per square inch.

Special Types. Lane. The Lane boiler, Fig. 43, was a combina-
tion of the fire-tube and flash systems. The main part of the boiler
was of the fire-tube type, with very
large tubes. Above this were several
ooils of brass tubing, the water entering
±\\e top and getting hotter as it passed
down the tubes until it was partly con-
verted into steam by the time it passed
Into the main part. The water was
here separated from the steam, falling
t:o the bottom of the boiler, while the
s*team was superheated by coming in
contact with the hot upper portion of
t:he fire tubes.

National. For the National Lon-
don busses a water-tube boiler is used, Fi «- 43 - ^^ Boiler
and these stand a great deal of abuse, often being run dry by the
carelessness of the drivers. As is shown in Fig. 44, these boilers are

Fig. 44. Water-Tube Boiler Used on National London Busses
Courtesy of Society of Automobile Engineers, New York City

built around a central steel drum, which is pressed from a single piece
of metal.

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BOILER ACCESSORIES AND REGULATION

Besides the main units of burner, boiler, and engine on the steam
automobile, there have to be many other small units, most of them
automatic in their operation, for the control of the fire, water feed,
and engine to meet the conditions of the wide variations in road and
driving conditions. These are the power pumps, the hand pumps,
valves, feed-water heater, condensers, and others.

Check Valves. In the lines where it is desired to have the fuel,

water, or steam pass in but one direction there are placed valves

which allow only this one-way passage and are known as check valves.

There are several types, including poppet, hinged, and ball checks.

The latter, Fig. 45, is very largely used and consists of a ball which

rests on a seat forming a ground, fluid-tight

joint. When the fluid is passing in the desired

direction it lifts the ball off the seat. The

body of the valve is so made that it keeps the

ball from being carried on down the line with

the fluid. As soon as the direction of flow or

pressure changes to the opposite direction the

Fig. 45. Crane Ball Check ba H dr °P S ° nt ° * ts Seat > closing the Valve

Valve against this opposite flow.

Check valves are used in many places in the fuel, water, and
steam lines, as is indicated by the diagrams further along. For
instance, there are check valves on the inlet and outlet sides of the
water pumps. When the piston is on the suction stroke, the inlet
check is open while the outlet check is closed, keeping the water
already pumped from being drawn back. As soon as the piston
starts on the delivery stroke the inlet check closes and the outlet
valve opens. This action applies to all the types of check valves.

If dirt lodges on the seats of a check it will leak and, if the dirt
cannot be forced off by vigorous action through the valve, the valve
must be opened up and the seat cleaned and possibly ground. In
most check valves this can be done without removing the whole
valve from the line.

Fuel System. Considerable fuel-carrying capacity is always
provided in automobiles, and for this reason there should always be
enough in the car for more than one run. Before starting out it is

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STEAM AUTOMOBILES

always well to see that there is plenty of fuel in the main and pilot
supply tanks. Not only is running out of fuel on the road very
inconvenient, but the running-dry of the tanks may air-lock the
pumps and cause a loss of considerable extra time in getting the

Fig. 46. Power Pumps of Stanley Engine

system back into smooth action. The above applies equally well to
the water supply.

As mentioned in the section on burners, the fuel is fed under
pressure. In some cases the pressure is carried on the main tank,
while in other cases it is carried by air or spring pressure on small
auxiliary tanks. The power and
hand pumps on steam cars are
of the plunger type.

Due to the interrelations be-
tween the demands for steam,
water, and fuel and the auto-
matic devices, one controlled by
the other, it is difficult to deal
separately with the various
units. For this reason one com-
plete fuel, water, and steam sys-
tem will be discussed and then

4=^

Fig. 47. Fuel Pressure Tanks on Stanley Cars

descriptions of other makers' units and methods of operation will be
taken up. The Stanley system will be used to show the relation and
operation of the various units.

Stanley Fuel, Water, and Steam Systems. Fuel System, On the
Stanley cars the main fuel tank is carried under atmospheric pressure
and the fuel is drawn from the tank by the power-driven pump,
Fig. 46. In series with the power fuel pump is a hand pump for use

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when the engine is not running or if the power pump should be out
of order. The small 'pressure tanks on the Stanley are shown in
Fig. 47. The fuel does not flow through the left tank, marked 2, but
merely rises and falls in it, the tank acting
as a pressure equalizer between the strokes
of the power pump, similar to the standpipe
in many city waterworks systems. Tank
number 1 , on the right, is filled with com-
pressed air, which is supplied by the power-
driven air pump or by the hand air pump. A
pressure gage on the dashboard show's the
operator what the pressure is on the tanks.
From the auxiliary tanks the fuel passes to
the vaporizer.

Since the fuel power pump has a capacity

greater than that usually demanded by the

burner an automatic by-pass valve, called the

fuel automatic relief, Fig. 48, is placed in the line. When the fuel

from the pump is at a higher pressure than is being carried on the

Fig. 49. Stanley Fuel System
Courtesy of Stanley Motor Carriage Company, Xewton, Massachusetts

pressure tanks, the needle valve of this fuel automatic relief is raised
and part of the fuel is returned to the main tank, as shown in the
layout of the fuel system, Fig. 49.

Should this needle valve fail to seat properly, it is probably due

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STEAM AUTOMOBILES

to dirt between the needle and the seat. This can often be removed
by taking the tension off the spring by unscrewing the adjusting nut
and then pumping fuel with the hand pump. If this does not cure
the trouble the whole valve should be taken
apart and cleaned and, if necessary, the needle
ground into the seat.

Beyond the pressure tanks there is a fuel
filter which should be watched for leaks and
cleaned every once in a while. Near the tanks
is also a pressure-retaining valve, which may be
closed by hand when the car is left standing,
the purpose being to keep the pressure on the
tanks, as it might otherwise be lost, due to slow
leaks in the lines, and thereby necessitate the
pijmping-up of pressure by hand.

Actual fuel supply to the vaporizer, and
hence to the burner, is governed by the steam
automatic regulator, or "diaphragm regulator",
as it is sometimes called, Fig. 50. This regula-
tor governs the relation between the steam
pressure and the fuel supply to the burner. It
consists of a metal diaphragm, clamped
between the cap and the body. When the
steam pressure rises above the predetermined
amount, the pressure against the diaphragm
causes it to bulge and thus move the rod
attached to it so as to keep the ball valve from
leaving its seat, thereby shutting off the fuel to
the boiler.

The strength of the spring determines at
what steam pressure the fuel is shut off. To
regulate the strength of the spring the adjusting screw is moved
in or out. The valve stem is provided with a stuffing box which
can be tightened up to stop leaks through the gland. The screw
locks the gland in place after the adjustment is made. Care must'
be taken not to get the gland too tight.

Upon the older Stanley models, in which gasoline was used for
the fuel of the main burner as well as for the pilot light, the line for

Stanley Steam
Automatic \ alve

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48 STEAM AUTOMOBILES

the latter was a branch of the main fuel line. In the newer models,
the pilot system is entirely separate, so that kerosene may be used for
the main burner. The pressure on the separate gasoline tank is
pumped up by a hand pump and should be kept at from 20 to 30
pounds per square inch. In leaving the pilot burning over night the
pressure will not fall over 5 to 10 pounds.

Water and Steam System. From the main water tank the water
is drawn by two opposite power-driven pumps. Fig. 46, and follows
the course shown in Fig. 51. A hand pump is also provided for U9e

Fig. 51. Diagram of Stanley Water System
Courtesy of Stanley Motor Carriage Company, Newton, Massachusetts

when the car is standing still or in case of a failure of the power
pumps. Beyond the pumps are by-pass valves, the opening of which
allows the water to return to the supply tank. The rear by-pass is
operated by the usual type of handle, while the one in front is con-
trolled by a lever on the steering post. The handling of these by-pass
valves will be taken up in relation to the general operation of the car.
On the way to the boiler, the water passes to the water-level
indicator, which is explained in detail in the following paragraph, and
then to the feed-water heater. Over the water pipes in the feed-water
heater the exhaust steam from the engine is passed. In this way

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STEAM AUTOMOBILES 49

much of the otherwise waste heat of the exhaust is given back by
heating the water before it reaches the boiler, resulting, of course, in a
saving of fuel. The feed-water heater also serves as a muffler for the
sound of the engine exhaust.

The water-level indicator is for the purpose of showing the opera-
tor the amount of water in the boiler. It consists of three tubes, Fig.
52, M , N, 0, which are brazed together. The middle one N is a part
of the water column, that is, its lower end connects with a pipe leading

Fig. 52. Diagram Showing Stanley Low-Water Automatic Valve with
Three-Tube Indicator Body

to the bottom of the boiler and its upper end is in communication
with the top of the boiler, so that the water stands in this column at
the same height that it does in the boiler. At the lower end of tube
N is the low-water try cock.

Tube M , at the left, is part of the water system from the pumps
to the boiler and, when the car is running, water is constantly passing
through it. The standpipe is closed at its upper end and at its
lower end is connected by a copper tube to the glass water glass on

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50 STEAM AUTOMOBILES

the dashboard in front of the driver. The standpipe, tube, and glass
form a U-tube which is filled with water, the level of which, when cold,
stands about an inch above the bottom of the glass.

If the water level in the boiler, and therefore in the tube N, is
above the top of the standpipe 0, the cold water passing through Af
on its way to the boiler will keep the standpipe comparatively
cool, and the water in the glass will show about an inch above the
bottom; but if the water in the boiler falls below the top of the stand-
pipe, it will no longer keep cool and the resulting heat will turn some
of the water in the standpipe into vapor. Since the end of the stand-
pipe is closed, the pressure of the vapor will cause the water in
the glass to rise, showing the driver that the water in the boiler is
getting low.

It is important to remember that when the water is high in the
glass it is law in the boiler. It should also be noted that the glass
gives the correct reading only when the car is running, and that when
the boiler is cold the water in the glass will be at the bottom whether
the boiler is full or empty. A false reading of the glass may also
occur from the heating-up of the indicator body when the car is left
•standing with steam up. This will make the water rise in the glass,
apparently showing the water to be low in the boiler even though it
were full. Directly upon starting the car, water will be pumped
through tube M and the indicator body will cool down, giving a
correct reading in the glass.

To fill the standpipe, U-tube and glass with water, the plug is
removed from the top of the standpipe and water is poured into the
glass faster than it can flow out of the standpipe. When all the air
has been forced out in this way, the screw is replaced while the water
is still running, but is screwed down only lightly. The water is then
shut off and, when the level in the glass has gone down to about an
inch above the bottom, the screw in the top of the standpipe is
tightened up.

In freezing weather an anti-freeze solution should be used in the
U-tube and glass. This can be made of equal parts of glycerine and
water or of alcohol and water. A test of the indicator can be made
when steam is up by opening the low-water pet cock until the water
rises in the glass and then pouring cold water over the body of the
indicator, which should cause the water in the glass to fall.

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STEAM AUTOMOBILES 51

When the boiler is cold the amount of water in it is determined
by opening the low-water pet cock. If water flows it shows that there
is enough in the boiler to allow firing up. If no water comes and a
wire run in the pet cock shows that it is not stopped up, water should
be pumped in the boiler by hand. When trying the water level by
the pet cock the water should be allowed to run several seconds so as
to be sure that it is not merely the condensation which may have
gathered.

If dirt or incrustation should stop up the lower end of the water
column, it would cause false readings of the indicator and try cock.
It is therefore important that this be guarded against by blowing
down the boiler regularly. The procedure in blowing down will be
referred to later.

Another protecting device of the Stanley is the low-water auto-
matic valve, which in its action and location is closely connected to
the water-level indicator. The purpose of this valve is to shut off
the fuel supply in case the water becomes low in the boiler. As shown
in Fig. 50, it consists of a valve B in the fuel line, an expansion tube
D and two rods C, the latter forming a framework or support.

When the water in the boiler and water column gets below the
try cock, the expansion tube D fills with steam and the heat of this
steam causes the tube to become longer. This expansion moves the
valve stem E, connected to the end of the tube, and this closes the
valve, shutting off the fuel to the burner.

In case the low-water automatic valve closes, first make sure that
there is water in the main tank, and that the pumps are working
properly. Then with both by-pass valves closed run the car as far
as it will go. By this time the pumps probably will have delivered
enough water to cover the bottom of the expansion tube, allowing the
fuel valve to open again. If not, the engine can be run with the
wheels jacked up or water can be pumped by the hand pump.

There are four other accessories to the Stanley and other power
plants, which have not yet been mentioned : the safety valve, steam
gage, siphon, and oil pump.

The safety valve is connected to the boiler and will blow if the
steam pressure exceeds the amount for which the valve is set. The
steam gage is placed on the dash and indicates the steam pressure
in pounds per square inch. The steam itself does not actually enter

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STEAM AUTOMOBILES

the gage, but the pressure in the system is communicated to the gage
by means of a tube filled with oil, which will not freeze in winter.

When it is desired to draw
water from a water trough or
some other "place from which it
cannot be run into the tank from
a faucet, the siphon is used. This
is a hose, a branch of which is
connected to the steam system
by a hand valve. One end is
placed in the tank-filler opening
and the other end, which is pro-
vided with a screen, is put in
the supply of water. The steam
is turned on and, due to an in-
jector action, draws the water up
into the tank.

Driven by the same mech-
anism which drives the Stanley
fuel and water pumps, is the oil
pump, Figs. 46 and 53. From the
oil tank the pump forces the oil
through the sight feed on the
dash, from which it is led into
the steam line to the engine.

In the oil pump, Fig. 53, the
plunger A is set in its extreme
foreposition, so that the end will
just come to the outlet. This is
done by removing the delivery
stub cap and delivery check ball
and inserting a small wire in the
outlet. When the driving cross-
head is in the extreme position,
the plunger should come to a
point where it will strike the
wire; the lock nut B is then tightened. This adjustment should be
looked to if the position of the driving crosshead becomes changed.

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To vary the amount of oil pumped, the distance between the
end of the adjusting piston C and the pump inlet is varied. The
shorter this distance the less the amount of oil pumped. The adjust-
ment is made by removing the cap D and adjusting the set nut E.
If the oil tank is allowed to run dry the pump may become air-locked,
and it is then necessary to disconnect the copper pipe and work the
pump until the air is expelled.

All ordinary steam-cylinder oil is not suitable for use in these
engines because of the high degree of superheat. The Stanley
Company recommend either the "Harris superheat steam-cylinder
oil" or the "Oilzum high-pressure superheated steam-cylinder oil".
Other makers recommend different classes of oils best suited to their
particular engines and these will be noted later.

Now that a general idea of the make-up and operation of the
power-plant accessories has been given in the description of
the Stanley layout, attention will be turned to the characteristics
of the accessories offered by other makers.

Doble. The details of construction of the Doble combustion
chamber and boiler have already been shown in Figs. 35 and 41, and
discussed on pages 34 and 40. The water level in the boiler is kept
at the half-way point by an automatic by-pass valve, which is oper-
ated by the expansion of a regulator tube. As the water rises in the
boiler, the tube is filled from an outside pipe with comparatively cold
water. The decided change of temperature causes the tube to
contract again, and the water is by-passed to the supply tank. The
steam pressure is maintained around 600 pounds by another automatic
device, which controls the fuel system.

From the upper headers of the generator sections, the live steam
passes into a manifold which leads it through the throttle valve and
then to the engine. From the engine, it passes back to the condenser,
being forced along by the following steam.

A non-rusting alloy is used for the seats of the throttle valve.
The valve, shown in Figs. 28 and 29, is a compound design, being a
combination of a poppet and piston valve. The piston portion regu-
lates the flow of steam, while the poppet serves to keep the valve in a
tight, or non-leaking, condition.

The force of the steam constantly coming from the engine causes
the steam to pass from the top to the bottom of the radiator condenser

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54 STEAM AUTOMOBILES

and, under normal conditions, the steam has been completely con-
densed to water before it reaches the bottom. This water of conden-
sation enters the water tank very near the bottom, so that any steam
which still remains will be condensed as it bubbles up through the
tank. Rapid acceleration from a slow speed or very hard slow pulling
are the two conditions under which some steam may remain uncon-
densed in passing through the radiator. As a safety measure, in case
of a very long stretch of slow heavy pulling, the water tank is pro-
vided with a vent at the top. With this condensing system, it is said
that a car will run 1500 miles on one filling of water.

Doble Lubrication. Another one of Doble's departures from
standard steam-automobile practice is in the matter of lubrication.
The throttle, engine valves, cylinder walls, water pumps, and interior
of the generator are all lubricated by regular gasoline-engine oil
instead of ^ the heavy steam-cylinder oil used in power plants.

This comparatively light mineral oil at once forms an emulsion
with the water, due to the shaking up from the roughness of the road
and the agitation of the feed water as the condensation enters the tank
from the radiator. The oil, therefore, is sent into the generator along
with the feed water and gives the interior of the tubes a very thin
coating of lubricant. How thin this is may be judged by the state-
ment that the generator temperature is 485° F. at the working pres-
sure of 600 pounds. This coating not only prevents the tubes from
rusting, but keeps scale from forming as it cannot stick to a greasy
surface. The oil in the water also prevents scale from forming in other
places and pipes, for it coats each particle of lime, etc., which may be
thrown down and keeps it from sticking to any other particle and
building up a deposit. It is this same oil that is carried over with
the steam that lubricates the throttle valve and cylinder parts. The
condenser saves the oil supply as well as the water, so that the lubri-
cant is used over and over again, and a car is said to run 8000 miles
on one gallon of oil.

Steaming Test. One of the main features claimed for the Doble
design is the short length of time required to raise steam to a working
pressure, that for ordinary running being 600 pounds per square inch.
The following test was recently given out by the company.

The generator had approximately 150 square feet of surface and
contained, when the water was at its normal level, 8J gallons. Corn-
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STEAM AUTOMOBILES

justion started with the water in the generator at 66° F. The first
■race of steam came in forty seconds.

Pressure
lb. per sq. in.

Elapsed Time

Pressure
lb. per sq. in.

Elapsed Time

Trace

100

40 sec.
1 min., 20 sec.

1 min., 45 sec.

2 min., 10 sec.
2 min., 25 sec.
2 min., 40 sec.
2 min., 50 sec.

700

800

3 min.

3 min., 10 sec.
3 min., 15 sec.
3 min., 20 sec.
3 min., 25 sec.
3 min., 30 sec.

200

300

900

1000

400

1100

500

600

1200

Ofeldt. Fuel, Water, and Steam Connections. Fig. 54 gives a
clear idea of the fuel, water, and steam connections of the Ofeldt

Fig. 54. Diagram of Connections for Ofeldt Boiler Feed and Fuel Systems
Courtesy of F. W. Ofeldt & Sons, Nyack-on-the- Hudson, New York

system, the burner and boiler of which have been described pre-
viously. The feed-water pump A and the fuel pump e are usually
on opposite crossheads of the engine, but to make the two systems
clearer they have been separated in the diagram.

The Ofeldt Company makes these accessories either for use as a
complete system, as shown in the diagram, or for use with other
units. The company does not make a complete automobile.

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56 STEAM AUTOMOBILES

An expansion tube N is the basis of the Ofeldt water regulator.
This tube stands at right angles to the middle point of the boiler
water column P, and when the water becomes low enough in the
boiler and column for the tube to fill with steam, the expansion causes
the closing of the water by-pass valve through the movement of the
linkage 0, M , L. When used with the Ofeldt water-tube boiler it is
claimed that a water-level glass is unnecessary.

Fuel regulation is accomplished by the diaphragm valve, tr.
This is made up of two concave discs with a steel diaphragm fastened
between them. Combined with the upper disc is the valve controlling
the fuel supply. When the steam pressure on the lower side reaches
the point for which the valve has been adjusted, the diaphragm pushes
upward, shutting off the fuel. Upon the decrease of the steam pres-
sure, the natural spring of the diaphragm again opens the fuel valve.
Where used with a pilot light the closing of the valve completely
shuts off the fuel to the main burner, but where no pilot is used just
enough fuel is allowed to pass to keep the fire burning.

Automatic Fuel Feed. Possibly the most interesting of the
Ofeldt accessories is the automatic fuel feed i, in which a spring is
used to keep the fuel under pressure. It consists of a brass cylinder,
18 to 36 inches long and 4 inches in diameter, which is plugged at one
end and capped at the other. Running the length of the cylinder is a
coil spring with a piston at one end. The engine fuel pump e, or
hand pump d, forces the fuel into the tank, pushing back the piston
and compressing the spring. This spring keeps the pressure on the
fuel the same as is done by the air tanks in the Stanley system. As
part of the pressure layout is a safety or by-pass valve J, which can
be set for the desired pressure on the fuel, the excess fuel from the
by-pass valve and from the leakage past the piston in the regulator
are returned to the fuel tank.

MANAGEMENT AND CARE OF STEAM CARS

In the preceding description considerable has been said as to '
the management and care of the units, but in this section some
further hints will be added on the operation of steam automobiles.

Management on the Road. As will be understood from the fore-
going, the operator's part in managing the power plant — other than
attention to the throttle — is ordinarily limited to watching the water-

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level indicator and managing the by-pass valve — if not automatic —
in accordance with the water level. When the level drops, the
by-pass valve must be closed, thereby causing all the water pumped
to enter the boiler. When the water level exceeds the proper height,
the by-pass valve is opened and water ceases to enter the boiler.
It is not practicable to open the by-pass valve part way, as this would
cause the water to go through the valve at boiler pressure and, in
time, the scouring action due to the pressure would make the valve
leak.

Blind adherence to the above rule will not always give as good
results as may be obtained through manipulation. For example, if
one sees a hill ahead, he can fill the boiler somewhat higher than its
usual level and give the added water time to get hot before the hill is
reached. This affords a reserve supply for surmounting the hill. In
the average hilly country, one can make a practice of pumping water
on down grades when little or no steam is being used and the heat of
the fire is available to heat the incoming water. Near the bottom of
the hill the by-pass valve is opened and the ascent taken in good
style. If the accumulated pressure has caused the fire to shut off, the
throttle may be opened just before the bottom of the hill is reached,
and the drop in pressure will bring the fire on while impetus is being
gained. It is a general rule for all classes of steam- cars that the fire
should, if possible, be "on" before an up grade is begun. By proper
management the fire may be kept burning continuously in a hilly
country, while power is used only on the up-grades.

In applying the above principles it should be remembered that
only the wetted inside surface of the boiler is available for making
steam. If the water is low, steam cannot be raised as rapidly as
when the boiler is full, assuming that the water is hot in both cases.
On the other hand, if the boiler is worked too full one may get wet
steam despite the superheater, with loss of power due to condensa-
tion. In an extreme case, enough water might even be carried through
to choke the clearance spaces at the cylinder ends. This would
probably result in a head being knocked out or a connecting rod or
crank bent, as the water could not be ejected quickly enough by the
lifting of the slide valve to save the engine from severe shock when
the piston reached the end of its stroke. A boiler of the Lane type,
in which the water is partly converted into steam in coils above the

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58 STEAM AUTOMOBILES

boiler proper, and in which the fire tubes are large enough to penra
combustion to take place inside of them, is an exception to the above
in that superheating takes place chiefly in the "boiler".

The more rapidly fuel is supplied to the burner, the hotter wil
be the fire. Where ample power is desired, therefore, the burne
is worked under more than ordinary pressure. In the Stanley cars
which carry pressure only in the auxiliary tank, 120 to 140 pounds i
recommended.

Firing-Up. The following remarks apply particularly to car
with the Stanley type of burner and boiler. In the case of the Dobk
car, the constructions are so different that many of the instruction?
will not apply. The Doble system has been described in detail in the
preceding pages, and the rea'der is referred back to these paragraphs
for the firing-up of the boiler, etc. As will be explained later, it i*
customary at the end of a run to blow down the boiler for the purpose
of ridding it of whatever sediment may be present. The blow-off
valve is shut when a few pounds of pressure still remain, and the con-
densation of this remaining steam should suck the boiler full of water,
provided the by-pass valve is closed. The presence of this water is
desirable to protect the superheating coil when the fire is started.
Therefore, if the car has a conventional fire-tube boiler with super-
heating coil beneath, the first step is to ascertain whether the boiler
is actually full. Close the by-pass (if open), open the upper try cock.
and if no water comes out, work the hand pump. See that the water
tank is full. Open the throttle and the drip valve on the steam chest
and continue pumping by hand till water comes out. Leave them
open while starting the fire, to allow the water to expand.

If there is no pressure in the fuel tank, pump it up to the mini-
mum working pressure by hand. Heat the pilot, either by burning
gasoline in a cup, by an alcohol wick, or by the modern acetylene
torch, as the case may be. When thoroughly heated, slowly open
the pilot-light supply valve. If a blue flame does not result, close the
supply valve and admit more gasoline to the cup.

After starting the pilot light, allow it to burn till the vaporizer
is hot, then open the main-burner valve carefully. If it fires back
into the burner, shut it off, wait a minute or two and try again.
Turn the burner to full height gradually. If the flame is yellow
or smoky, it is not getting enough air; if it is noisy and lifts off the

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STEAM AUTOMOBILES 59

burner, it is getting too much air. Once adjusted for a given fuel
pressure, the nozzle or air shutter should not need changing.

While the water is getting hot, the oiling up can be attended to.
As soon as the pressure begins to rise, water will issue from the drip
cock on the steam chest. Close this cock and the throttle valve as
soon as clear steam comes out.

When pressure reaches 100 or 200 pounds, get into the car, throw
the reverse lever to its full forward or backward position, open the
throttle slightly and then close it at once. Repeat till the engine
starts. With some yards of clear way, work the reverse lever back and
forth with the throttle open only a crack, so that the car "seesaws"
slowly. This will work the water out of the engine and warm up the
cylinders till the entering steam ceases to condense. This process
must not be hurried. An attempt to cut it short is likely to result in
damage to the engine. As long as water is present the engine will
run jerkily. When it runs smoothly the car is ready to start.

On starting, the first few blocks should be run slowly to com-
plete the warming-up process. If the air pressure is below normal
the air pump should be kept going.

At the End of a Run. On finishing a run, the boiler should be
blown down with the fire turned off. This should be done by open-
ing the blow-off valve near the bottom of the boiler. The escaping
water will carry with it all the mud and precipitate that have accumu-
lated. Close the blow-off valve at about 100 pounds, and the sub-
sequent condensation will fill the boiler by suction from the tank.
If the water in the tank is covered with oil, the end of a hose should
be inserted and the tank flushed out to get rid of the oil. It is a good
plan to put a cupful of kerosene into the tank. It will not only
loosen whatever oil may be clinging there, but will help loosen the
scale liable to form from hard water.

A thermostat water-level indicator operates only when steam
is up. When the boiler is cold it indicates high water whether water
is present or not. When the car is running, a faulty reading of the
water level is usually soon noticed, and if it is overlooked there is
still protection of the fusible plug. If, however, the boiler should
be fired up with no water in it, the fusible plug would melt without
the fact being heralded by escaping steam. Therefore, the fusible
plug, like the water-level indicator, is useful only when steam is up.

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60 STEAM AUTOMOBILES

Engine Lubrication. For the older cars not using superheated
steam, the regular power-plant steam-cylinder oil is usually recom-
mended. This is a mineral oil mixed with tallow to make it hold on
the wet cylinder walls. It often contains graphite. This type of oil
will not stand the high temperatures of superheated steam, and special
oils must be used. As an example, the Stanley Company has recom-
mended either "Harris superheat steam-cylinder oil" or "Oilzum high-
pressure superheated steam-cylinder oil". The Doble uses the same
kind of gasoline-engine oil as is used by the ordinary motor-car driver.
Other engines use different grades of oil to the best advantage, and it
is best in each case to find out the maker's recommendations.

The Fusible Plug. If the fusible plug blows out when the car
is running, the escape of steam may be shut off by closing a valve
usually interposed between the boiler and the plug. The fire should
be shut off at once and, if possible, the car should be run to reduce the
pressure, thereby allowing the boiler to cool somewhat. When the
drop in pressure compels a halt, close the by-pass valve and pump
water in by hand till it shows in the lowest try cock. Then, after
replacing the fusible plug, the fire may be relighted and the water
level restored while the car runs.

If the plug blows simply because the by-pass valve has been
open too long, the by-pass can be closed, the main fire shut off, and
the engine run by jacking up the rear wheels, till water shows in
the lowest try cock.

Causes of Low Pressure. Low pressure is generally due to
insufficient fire. If the burner pressure is low, steam will not be made
rapidly. If the burner pressure is all right, the burner nozzle may
be clogged or the vaporizing tube may be choked with carbon. The
nozzle may usually be poked out with a bent wire without turning off
the fire. If, however, the vaporizer is clogged it will have to be
removed when the car is cold and cleaned, with a drill or otherwise,
as the makers direct.

Occasionally the valve controlled by the diaphragm regulator
may be choked, and rarely the main-burner valve. Either can be
cleaned by disconnecting and running a wire through.

Occasionally the pilot light may clog in the same way, usually
at the nozzle. The remedy is the same as for the main burner.

If the air pump fails to raise the pressure on the fuel tank to

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STEAM AUTOMOBILES 61

the required degree, it is probable that the intake or outlet check
valves leak. If, as is likely, they have oil on them, the oil may have
gathered dust. The valves should be taken out and cleaned, and a
drop of oil put on them to make them tight.

The various packings about the engine and auxiliaries require
occasional tightening, and once in a while new packing is necessary.
If the new packing is soft, like wicking, it may be put on top of the
old, otherwise the old must be removed. The packing should not
in any case be tighter than necessary to prevent leakage, for unnec-
essary friction would thereby be caused. A slight leakage about the
water and air pumps may be permitted to save friction. As the hand
pumps are rarely used their packings can be looser than those of the
power pumps.

Scale Prevention and Remedies. In sections where hard water
is used, the subject of scale is a serious one, and its treatment will
depend on the character of the mineral contained in the water. Fre-
quently it is possible to precipitate the mineral before putting the
water into the tank. Sometimes the addition of a small quantity of
lime will do this, sometimes carbonate of soda or "soda ash". Still
other waters are successfully treated by adding caustic soda. Some-
times the simple addition of kerosene to untreated water will loosen
the scale as above indicated. If these remedies are not successful,
the user is advised to send a sample gallon of water to a maker of
boiler compounds and have it analyzed, after which a suitable com-
pound can be recommended. Scale allowed to accumulate by neg-
lect is not only very detrimental to the boiler by interfering with the
free flow of heat, but it also seriously reduces the steaming power.
Instances have been known of the steaming capacity of boilers being
reduced fifty per cent or more by scale. At the same time the shell
and tubes get hotter than they should, resulting in unequal expansion
and leakage.

Filling the Boiler. Before firing up, be sure that the boiler and
superheaters are full. To be sure of this, open the throttle valve and
steam-chest drip, close the by-pass valve and work the hand pump
until water comes from the steam-chest drip. If more convenient
fill the boiler from the town supply by means of the coupling fur-
nished for this purpose, connecting to the blow-off valve. Never
light the fire until you are sure that the boiler is full.

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62 STEAM AUTOMOBILES

At the end of a run open the blow-off valve at the front of the
boiler, and blow down to about 100 pounds. Fill the water tank and
close the by-pass valve, and the condensing steam in the boiler will
siphon the boiler full. Before blowing down, see that the pilot light
is out, as well as the main burner. It can be extinguished by blowing
into the pilot mixing tube.

Raising Gasoline Pressure. If the pressure tanks are empty
and the pressure zero, proceed as follows:

Open the hand gasoline-pump valve and work the pump till
the air gage registers 10 or 15 pounds. Tank 2, Fig. 47, is now full of
gasoline, and tank 1 is full of compressed air. Attach the hand air
pump to air valve and pump air into tank 1 till the gage indicates
80 or 90 pounds, which is the working pressure for the burner.

If now the fire is lighted and the car stands still, the pressure
will gradually drop, but may be raised in a moment by working the
hand gasoline pump. When the car runs, the power pump main-
tains the supply.

The air in tank 1 is gradually absorbed, and additional air is
required. This is indicated, first, by the vibration of the air-pressure-
gage needle when running; second, by a rapid drop of pressure when
the car stands still. In case of doubt whether the drop is due to lack
of air or to a leak in the automatic or pump valves, close the pressure-
retaining valve. If the pressure still falls the air is insufficient.

Occasionally empty the pressure tank by opening valve Z>, and
refill in order to determine definitely the amount of gasoline in it.

If the car is to stand some time with pilot burning, close the
pressure-retaining valve to prevent the gasoline from leaking back
through the valves and automatic. Be sure to open again on starting.

General Lubrication. On page 60, are mentioned the different
grades of oil suitable for cylinder lubrication in the various types of
engines. The lubrication of the cylinder walls and valves, however, is
not the end of the subject, for, wherever there are two moving surfaces
in contact, there must be lubrication in order to keep the friction losses
at a minimum. Useless friction in the running parts of the engine and
chassis of the car means an increased consumption of fuel. This,
however, is often of secondary consideration in comparison with the
wear and resulting repair bills, often caused by lack of lubrication.
When a bearing becomes dry, it usually heats up and expands, and

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STEAM AUTOMOBILES 63

in case this is continued to the point of "freezing", the car may be
completely disabled on the road.

Of course all parts of the car do not have the same amount of
motion and, therefore, do not require the same amount of lubrication.
All makers of cars issue instruction books for each model and, when
possible, the operator should provide himself with a copy and follow
the oiling instructions. This, however, is often impossible, and it is
then a matter of good judgment based on the known requirements of
other cars. Outside of the power plant there is no particular differ-
ence between the construction and care of a steam- and a gasoline-
engine driven car, and the lubrication chart of any of the later makes
can be safely followed.

In the modern Stanley and Doble types, the crankshaft, cross-
head, and other moving engine parts, other than piston, together with
the rear-axle bearings, are all lubricated by splash, the crankcase being
thoroughly oil-tight. The level of this oil should be inspected every
two months, although it will probably not need renewing that often.
Some of the older cars require that the eccentric be given a squirt
of oil daily, by a hand gim. It is a good habit to give all grease cups
a turn-down each day.

Water Pump. If the water pump fails to work, first see if the
tank is empty. In addition to this there are three other causes to
which failure is mainly due, viz, (1) The pump may be air-bound. To
remedy, open the by-pass valve and run the engine. The air will work
out readily, since there is no pressure against it. (2) The check valves
may leak. There are three check valves, one on the pump intake,
another on the outlet, and the third at the boiler. The intake valve
is the most likely to leak. Remove the valve cap and clean the valve
ball and its seat, being careful not to scratch them. If the boiler
check valve is leaking, it will permit steam to escape into the water
tank when the by-pass valve is open. This valve can only be exam-
ined when there is no pressure. (3) The pump packing may leak.
Tightening the packing nut generally suffices, but occasionally
repacking is necessary. Do not screw the packing nut tighter than
is necessary, as it causes needless friction; a slight leakage may be
tolerated. In case the power pump fails, use the hand pump, first
running with the main fire off till the pressure is reduced to about 100
pounds. After pumping, close the valve with the pump plunger in.

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64 STEAM AUTOMOBILES

Gasoline Pump. In most respects the gasoline pump resembles
the water pump. If it becomes air-bound, it can be primed by using
the hand gasoline pump, which is much larger and, drawing through
the power pump, will suck out the air.

The gasoline pump packing should not leak at all, as it is both
wasteful and dangerous. The pump is so small that adjusting is
seldom needed.

If the hand gasoline pump becomes air-bound, unscrew the valve,
which is open when the hand pump is used, till it comes out. Press
the thumb over the valve-stem hole when the pump plunger is pulled
out, and lift it off when the plunger is forced in. Repeating this
several times will expel the air.

If the hand gasoline pump and hand water pump work together,
the packing nut on the gasoline pump should be just tight enough
to hold the gasoline, and the water pump should have its packing
so adjusted that the pump will run perfectly free.

To pack the gasoline pump, put in first a thin leather washer,
then three of the special packing rings supplied by the makers, then
another thin leather washer, and screw the stuffing-box nut only
hand tight. Do not use a tool to tighten it, otherwise the plunger
will cut out the packing.

Care of Engine Bearings. If the engine is regularly lubricated
the bearings will seldom require adjustment. If the bearings show
the slightest discoloration from rust they have been insufficiently
oiled. Adjustments are made as follows:

The crosshead guides are taken up by screwing down the nut
on the bolt holding the frame rods together. The crosshead balls
must be under sufficient pressure to keep them from slipping.

The wrist pins are taper and are adjusted with a screw held by
a lock nut. First loosen the lock nut, turn up the screw till it stops,
then back it one-eighth turn and tighten the lock nut.

The crankpin ball bearings are adjusted by removing the
bolt, taking out the plug, and reducing it slightly by filing. When
correctly adjusted the bearings should have no perceptible play.

The main bearings and eccentrics can only be adjusted after
the engine is taken out of the car. They are adjusted to take up lost
motion by filing or grinding down the face of the bearing cap, which
must be very carefully done.

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Be sure the engine-frame hangers are properly adjusted. Should
the nuts work loose, the front end of the engine will sway, to the
damage of the engine case and gears. In adjusting the engine-frame
hangers do not set them up so tight that they will not swivel around
the rear axle. If necessary insert shims of paper or thin brass,
removing the rear engine case to gain access.

Operating the Cut-Off and Reverse. In the more recent Stanley
cars the cut-off is variable from one-quarter to one-half stroke. On
the engine is a quadrant from which the reverse lever works in con-
nection with the reverse pedal. The quadrant has one notch, into
which a dog attached to the reverse lever drops when the engine is
"hooked up", that is, operating on short cut-off. To hook up the
engine, press on the reverse pedal only. To release the dog, press a
pedal beside the reverse pedal, called the clutch pedal. This releases
the reverse pedal and a spring pulls it back, allowing the engine to cut-
off at half-stroke. The car should always be started with the reverse
pedal released, and the cut-off should not be shortened until the
engine attains good speed. If it operates jerkily, release the reverse
pedal by pressing the clutch pedal.

Care of the Burner. If the car does not steam well, look at the
fire first. See that the gasoline pressure is not below 100 pounds.

If the pressure is right, the gasoline line may be clogged in the
automatic valve, vaporizer, burner nozzle, or main-burner valve.
If the burner has two mixing tubes, see if both sides are affected;
if so, the trouble is probably in the automatic valve. If the two
burner flames are unequal, the trouble may be in the vaporizing
tubes or the nozzle, more likely the latter. Clean the nozzles by run-
ning a small wire through them with the screw out, or by using a bent
wire without removing the screw.

If the vaporizing tubes are clogged, uncouple at the back of
the burner, take out the bundle of wires from the tubes, and clean
the tubes and wires thoroughly, using the bundle as a swab. Extin-
guish all fire before beginning.

If the pilot-light nozzle becomes clogged, use a screwdriver
to turn the horizontal nozzle screw back and forth. A wire projects
from this screw through the nozzle orifice and turning the screw
causes the wire to clean the nozzle. Do this only with the pilot
burning.

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66 STEAM AUTOMOBILES

To regulate the air received by the pilot, bend the pilot vaporizer
tube slightly away from the mixing tube for more air, or inward for
less air. The pilot should burn with a blue flame slightly tinged
with yellow, and may be adjusted while lighted.

Never use a reamer for cleaning either the pilot or main-burner
nozzle, as it is likely to enlarge the hole, which is that of a No. 62 drill.

Sometimes after the automatic valve closes, the gas pressure
at the nozzles will reduce gradually, causing the burner to light-
back. When next the automatic valve opens, the fire will burn inside
the mixing tubes with a roaring sound. This sound should be the
instant signal for closing the main-burner valve and allowing the
mixing tube to cool.

If the burner should fire back frequently and with a sharp
explosion, it would indicate either a leak in the burner or a leak of
steam in the combustion space. To test for a steam leak, first get
up steam pressure, then take off the burner and examine the boiler,
then run the front wheels against something immovable and open
the throttle valve to see if steam escapes from the superheaters.

To Adjust the Throttle. If the throttle valve leaks it must be
reground or a new valve substituted. It may, however, appear
to leak owing to improper adjustment. There should be some
tension on the valve stem when the lever is locked in the closed
position. There is a distance rod running from the body of the
throttle valve through the dashboard close to the throttle^valve
stem. To increase the tension on the throttle, adjust the nuts on the
distance rod.

To Adjust the Automatics. To carry a higher steam pressure,
screw the adjusting screw on the automatic valve further in; for a
lower pressure, screw it out. The same regulation of the gasoline
relief valve will produce similar variations of the fuel pressure.

To Lay Up for the Winter. Run the car, on the road or with
the rear wheels jacked up, till everything is hot, then extinguish the
fire and blow off the boiler. While steam is escaping, open the
safety and siphon valves and take out the fusible plug to clear them
of water. Empty the tank, take off the caps of the check valves,
and blow into the suction holes to clear the water from the checks
ahead. Take off the water indicator and empty it, unless it is filled
with non-freezing mixture.

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General Remarks on Operating. The commonest fault of
Stanley operators is opening the throttle too abruptly on starting.
This is bad enough if the cylinders happen to be clear of water;
if they are not clear, the results may be destructive. Always start
slowly, and do not come up to road speed till the engine runs
smoothly.

Never open any of the valves more than two or three full turns.
They are screw valves, and if turned a dozen or more times they
will come clear out.

Practice reversing where you have plenty of room. The ability
to look and steer backward while operating the reverse pedal and
throttle is not a natural gift. After reversing, be sure that the pedal
has been released, by pressing the clutch pedal before giving steam.

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COMMERCIAL VEHICLES

INTRODUCTION

Development of Field. While the development of the com-
mercial car was slow at first owing to the numerous shortcomings
of early types, it has advanced with wonderful rapidity during the
past few years and bids fair to supersede, in a comparatively short
time, the use of the horse-drawn vehicle for business purposes, not
only in the large cities but also on the farm. As in the case of the
pleasure car, Europe led in the development of the automobile for
transportation purposes, chiefly with military necessities in view, as
without power-driven vehicles it would be impossible to move the
enormous food and ammunition supplies required by an army of
present-day proportions. However, American manufacturers have
advanced so rapidly in the production of commercial cars during the
past few years that in 1916 the registration of New York City alone
showed a greater number of these vehicles than were reported by the
census of 1915 for the whole German Empire and more than half the
number reported in service in Great Britain during the same period.
Scope of the "Commercial Vehicle". It is important to know
the reasons for the revolution which is now in active progress, as well
as to become familiar with the prevailing practices in America and
abroad in the construction, operation, and maintenance of that large
and varied class of automobiles employed exclusively for business
purposes. Regardless of type, class, or method of propulsion, these
are commonly referred to as "commercial vehicles". This classifi-
cation embraces not only motor delivery wagons and trucks for the
transportation of merchandise, but also taxicabs, omnibuses, sight-
seeing vehicles, motor road trains, farm tractors, emergency repair
or tower wagons for street-railway service, and also vehicles for
special municipal service — ambulances, patrol wagons, fire engines,
street-sprinkling and garbage-removal wagons, and the like. In fact,
it may be said that any automobile not devoted to pleasure is a com-
mercial vehicle, and, as was to be expected, the first types of these

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vehicles were merely pleasure cars transformed to suit the needs of
the occasion. To a certain extent, this still continues to be the case-
Standard Design. Whether it be electric-, steam-, or gasoline-
driven, the general design of the motive power, as well as that of its
transmission to the driving wheels, is practically the same in the
commercial vehicle as it is in the pleasure car, except that the chain
drive has now almost disappeared on the latter, and all the com-
ponent parts — bearings, frames, axles, steering gear, and compen-
sating mechanism — are the same. In other words, the chassis in
both cases is composed of similar members. For the sake of brevity
in the present treatise, it is assumed at the outset that the reader
has become familiar with motor-car engineering so far as it relates to
pleasure-car construction; that he understands, from previous study
and the actual handling of machines, the theory of the operation of
the internal-combustion engine; that he is conversant with the dis-
tinguishing characteristics of the several types of engines as well as
with their advantages and limitations; and that he is acquainted with
the types of transmission systems ordinarily employed on pleasure
cars — in brief, that he understands any reference to component parts,
to their functions, and to their relation to one another, without the
necessity of explanation.

In common with the pleasure car, the commercial vehicle is
capable of traveling at various speeds wherever road conditions will
permit it to go. Both comprise in a single entity a wheeled vehicle
suitable for transportation purposes, fitted with an independent, self-
contained power plant, and both present the same engineering prob-
lems so far as they relate to the construction of the motor, its control,
and the transmission of its power to the road wheels, the design of the
running gear, and the control of the vehicle itself. Divergence in
practice is encountered with the consideration of the purposes for
which each vehicle is designed. The pleasure car is not intended to
be a very efficient vehicle. Its carrying capacity bears a compara-
tively insignificant ratio to its total weight, and, usually, the car is not
designed to work under the same severe and continued conditions
of service that are the first requirements of the commercial vehicle.
It must be capable of high speed with its maximum load of passen-
gers and must combine reliability with endurance to an extent
sufficient to meet the demands of its owner when on pleasure bent.

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Classification. In order to make the subject as clear as possible
and to facilitate reference on the part of the student, industrial motor
vehicles as a whole have been classified, first, by their motive power;
and second, by the uses for which they are intended. Thus there
are, today, in the order of their relative importance:

Motive Power

Types of Vehicles

Electric vehicles
Gasoline-driven vehicles
Gas-electric vehicles
Steam vehicles

Industrial electric trucks

Delivery wagons

Trucks, vans, and similar freight carriers

Passenger vehicles — stages, busses, taxicabs, sight-seeing
cars, etc.

Municipal vehicles — patrol wagons, ambulances, fire appa-
ratus, garbage-removal wagons, street sprinklers, etc.

Special types — railway tower wagons, emergency repair
wagons, farm tractors, road trains, etc.

This classification has been made advisedly, for, though kerosene
and alcohol are being experimented with as fuels for the internal-
combustion engine and particularly for commercial purposes, by
far the greater majority of types marketed at present are driven
by gasoline fuel.

Each of the foregoing principal divisions is susceptible of further
subdivision, but this is neither necessary nor desirable. Commer-
cial motor vehicles are now built for almost every conceivable
purpose involving freight hauling or the transportation of pas-
sengers and include many special uses, such as hauling huge reels of
telephone cable and drawing the cable through the underground
conduits, transporting and hoisting safes and pianos, delivering coal
with special dumping wagons, and the like. They differ only in the
special equipment with which they are provided for the service in
view, and, as their construction otherwise is the same, it would only
lead to confusion to attempt to consider them separately.

ELECTRIC VEHICLES

Range of Use. Owing to the general recognition of its simplicity
and economy, which has been brought about by a co-operative
propaganda fostered by the electric lighting and power companies,

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the growth of the use of the electric commercial vehicles during the
past few years Tias been little short of phenomenal. One New York
firm alone uses nearly 350 electric delivery wagons, several have
nearly 100, while no fewer than forty-five have "fleets" of 10 cars or
more. All told, there are several thousand electric vehicles in New
York City and more than 100 garages and charging stations, while
the demand for current has been so great that the minimum for
charging batteries has recently been reduced to $10 per month.
Current is supplied at a preferred rate under special contract, which
calls for the charging of the batteries during those hours of the night
when the load on the central stations is lowest.

Advantages of the Electric Type. Simplicity. One of the chief
advantages of the electric vehicle, when judged from the purely com-
mercial point of view, is its great simplicity, which, to a very large
extent, solves the labor question that has proved such a deterrent to
the adoption of the gasoline vehicle for commercial service. As the
duties of the driver of an electric vehicle do not extend beyond its
actual starting, stopping, and guidance while under way, anyone
who has been accostumed to the use of horses can master its operation
in the course of a few hours. This lalso appears to be equally true
of men who have never driven any type of vehicle previous to their
taking the wheel or steering tiller of an electric. Apart from the actual
mechanical control of the vehicle, the driver's only other care is to
keep informed as to the state of charge of the battery by watching
the voltmeter, in order to prevent running the car with the batteries
exhausted, as this is very detrimental to their continued usefulness.
However, as the batteries of most commercial vehicles are charged
every twenty-four hours and the car run is planned to lie within its
traveling radius on a single charge, with a factor of safety allowed in
addition, this is not a very onerous duty. The further requirement
of noting the current consumption on starting and running, as indi-
cated by the ammeter, in order that any defect in the operation of the
running gear of the car may be detected and remedied, is also a very
simple one, so that an unskilled driver is available at a correspond-
ingly lower charge for labor cost in the operation of the vehicle. The
adoption of the ampere-hour meter showing the actual consumption
of battery energy has simplified the task of the driver still
further.

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Efficiency and Long Life. Broadly speaking, short runs with

many stops are the province of the electric, so that probably 80

per cent of all average city deliveries come within its economic field.

I*ts labor cost is much lower than that of the gasoline car, since an

unskilled hand can operate it efficiently, while one man at the garage

can take care of nearly twice as many electrics as of gasoline cars.

The electric is easier on tires, owing to its reduced speed, insurance

rates are lower, and its depreciation can be figured on a much more

favorable basis, as it has been shown to have an average effective

life of ten years. The fact that all its moving parts revolve has a

most important influence on its low maintenance cost and reliability,

many electric trucks showing an average of 297 days in service of

the 300 working days in a year.

Power Efficiency. The amount of power available on a single
charge of the batteries without unduly increasing the weight is so
limited that in the design of the electric great care must be taken
to eliminate friction and other sources of power loss at every possible
point. This is further necessitated by the gradually decreasing
efficiency of tne batteries with age. Starting with 80 per cent
when new, the efficiency may <*k>p rapidly to 50 per cent or below
unless the batteries are properly maintained, which is likewise true
of the transmission efficiency of the running gear of the vehicle; so
that while unskilled labor may be employed for the operation of the
vehicles this is not the case where their maintenance is concerned.
Power losses due to the tires are also an important factor, and as
the pneumatic tire can very seldom be considered for commercial
service, the same degree of efficiency is not obtainable from the busi-
ness electric wagon as from the pleasure type employing the same
motive power. Road conditions must also be considered — despite the
fact that electrics are employed almost exclusively for city or near-by
suburban service — as mud, snow, and ice in winter, and poor pave-
ments at any time .cause an increase in the current consumption.

ELECTRIC DELIVERY WAGON

General Specifications. Whether considered from the point of
view of design and construction or from that of operation, the
electric delivery wagon is, without doubt, the simplest vehicle in
the commercial field. As already mentioned, its operation may be

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mastered in a comparatively short time, either by the ex-horsedrive?
or by a person who has never had any experience in the control of a
vehicle, so that the labor cost — always an item of importance in thb
field — may be materially reduced without fear of the equipment
suffering in consequence. It is usually customary with manufac-
turers of these vehicles to adopt a standard form of design, which i>
employed throughout in every size listed by the same maker, the only
differences being those of dimension, load capacity of the vehicle.
and capacity of the battery to take care of the increased weight.

Package delivery wagons and express wagons of the electru
type have a useful load capacity ranging from- 1000 to 2000 pounds.
though a very few of less than 1000 pounds' capacity were employed
at first. The 40-mile run is standard and is based on an average
speed of 10 to 20 miles an hour, including stops, as the necessity
for frequently stopping and re-starting the car in delivery service
has an important bearing on the mileage of which the car is capable
on a single charge. The latter is naturally figured on the maximum
efficiency of the car as a whole, so that in practice this is seldom
fully realized, owing to the deterioration of the batteries in service.

Design. The electric has progressed through the stages repre-
sented by the angle-iron frame, the armored wood frame, and the modi-
fications of the two as employed on gasoline cars to the now generally
current type of pressed-steel frame. This frame has the advantage
of being extremely strong for its weight. It is composed of side and
transverse members produced in hydraulic presses directly from
steel plates of about T V-inch thickness, these members being riveted
together and further reinforced by gussets at the corners. On
account of the height of the vehicle, the frames are made perfectly
rectangular and without either a drop or narrowing forward.

The types of suspension employed also show the same variations
as are to be found in the gasoline-d riven cars, some of the smaller
electrics having the full elliptic springs ordinarily employed on
wagons, while intermediate and heavy vehicles have either straight
semi-elliptic springs front and rear or a half-platform type of sus-
pension in the rear. A study of the Baker and General Vehicle
types of delivery wagons and trucks will show how closely they
approach, as a whole, to what is considered general practice in the
automobile field.

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Because of the heavy loads carried and of the fact that solid
tires are used, the entire running gear has to be planned on a very
liberal scale. This is likewise true of the springs. While it is desir-
able that the latter afford as much protection to the mechanism as
possible, sufficient stability to carry the load is of more importance
than flexibility, as the comparatively slow speeds do not occasion
the violent shocks met with in the pleasure car.

MOTIVE POWER

Type of Motor. As already mentioned, the motive power of

the majority of smaller electric vehicles consists of a single motor,

and, in several makes, such as the Waverley, G.V., G.M.C., and

Detroit, this practice extends to heavy units, with a corresponding

increase in the efficiency of the vehicle as a whole. In order to keep

down the weight as well as the space occupied, these motors are very

small for their power output, and consequently have to be wound for

high rotative speeds. They are usually of the series type of the

General Electric or the Westinghouse make and are designed to

carry heavy overloads for short periods, to enable the car to pull out

of a bad place, to start with full load on a heavy grade, or to meet

similar emergencies, the motor, under such conditions, delivering

an amount of power greatly in excess of its normal rating.

Motor Suspension with Chain Drive. Since the use of spur-gear

drives has decreased, the motor is usually suspended from the frame

by means of transverse members riveted to the side rails and is

placed near, or slightly forward of, the center of the chassis, in

order to give the best distribution of weight. This is an advantage

not obtainable when the motors are hung from the rear axle or too

close to it. In view of the high speed at which the motors run — 1800

to 2000 r.p.m. or more — a reduction in two stages is necessary to

avoid the employment of excessively large sprockets. The first step

is from the motor to a countershaft by means of a single silent chain

of the Morse or the Renold type, the motor being suspended in such a

manner that it may be moved a short distance one way or the other

\ to permit the adjusting of this chain to the proper tension, Fig. 1.

The large sprocket on the countershaft, which serves to cut down the

speed in the proportion of about 1 to 5, also embodies a differential,

or compensating, gear of the usual bevel or spur type, thus making

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it possible to employ a solid one-piece axle instead of weakening
the latter by inserting the balance gear in it. This is an important
feature, as the rear axle must bear 60 to 70 per cent of the total weight
of both the car and the load. From the countershaft, chains are run
to each of the driving wheels. The relative positions of the counter-
shaft and the rear axle are maintained by heavy adjustable radius
rods, attached forward to the outer ends of the countershaft and, at
the rear, to the axle. These rods take the stress of the drive off the

Fitf. 1. Motor Suspension and Silent-Chain Drive on Baker Trucks

springs and counteract the tendency of the chains to draw the rear
axle toward the countershaft, under the pull of the motor.

Motor Suspension with Shaft Drive. On light delivery wagons of
the shaft-driven type, three methods of motor suspension may be
noted. In the first method, the motor is placed just forward of the
rear axle, its housing being practically integral with that of the axle.
Either a worm drive permitting of a single-speed reduction or a two-
speed gear through spur gears is employed. As the motor moves with
the axle and their relations are fixed, flexible joints are not required.
A modification of the first method consists in placing the motor under
the car at about the center and mounting it on a flexible suspension
so that it can move under stress without disturbing its alignment;
while the third method provides for taking such stresses on universal
and slip joints interposed between the motor and the rear axle.

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The relative locations of the various essentials of a deliver;.
wagon of the single-motor side-chain-drive type # are clearly shown
in Fig. 2 that illustrates a G.V. chassis of 4000 pounds' capacity, this
being the same except for the difference in size.

Worm-Gear Transmission. While the power is transmitted
through a combination-chain drive, i.e., silent chain for the first
reduction and roller chains for the final drive, on the majority of
delivery wagons, the practice of utilizing the worm drive, which has
recently been adopted on the pleasure cars, has also been taken up
in this field on the light vehicles. An example of this is represented by

Fig. 3. Hear Axle of Commercial Electric Delivery Wagon

the G.V. 1000-pound delivery wagon, equipped with a single motor
driving through a propeller shaft having two universals and with
a David Brown (British) type of worm-gear rear axle. On machines
of this class, it is customary to mount the motor on a flexible support,
which permits it to adapt itself to variations in the angularity of
the propeller shaft, thus reducing the load imposed on the universal
joints and, at the same time, avoiding the effects of torsional stresses
on the motor. As the location of the motor is such as to prevent
the suspension of the battery below the frame in the usual cradle,
it is carried forward under a bonnet, or hood, and the wheel-base of

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Fig. 4. G.M.C. Chassis with Combination Shaft and Chain Drive

the chassis correspondingly lengthened. This is not the case with
the Commercial worm-driven delivery wagon, as in this instance the
motor is placed almost directly on the rear axle, as shown in Fig. 3,'
thus eliminating the propeller shaft and the necessity for universal
joints. The spring suspension of the motor will be noted protruding
above its forward end.

Fig. 5. Motor, Drive Shaft, and Jackshaft Assembly for G.M.C. Electric Wagon

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Shaft and Chain Transmission. The G.M.C. (General Motors
Company) electric embodies a combination of shaft and chain drive,
as shown by the chassis, Fig. 4. This drive incorporates an ingenious

Fig. 6. Details of Motor Mounting, Brake, and Drive, G.M.C. Electric Delivery Wagon

feature consisting of the use of a spring steel shaft, as shown by the
detail view, Fig. 5. The design of these cars, as shown by the chassis,
is standard for all capacities ranging from a 1000-pound delivery

Fig. 7. Chassis of Waverley 5-Ton Electric Truck, Showing Battery Installation

wagon up to a 6-ton truck, and, in each case, the section of this shaft
is calculated to transmit the power necessary, with a predetermined
degree of flexure in starting, which serves to cushion the mechanism

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as well as the tires. The pin attachment at the motor and the bevel-
gear-driven countershaft eliminate the necessity for universal joints
in this member while still permitting a rigid mounting of the motor
on its sub-frame. As will be noted in Fig. 6, which shows the details
of the complete drive, this sub-frame is carried in bearings on a
tubular transverse member, thus allowing for relative movement in a
longitudinal plane, the shaft itself compensating for torsional stresses.
Unit-Wheel Drives. Mention has already been made of the
abandonment of two-motor drives on comparatively light cars, as
well as the successful employment of a single motor on vehicles up
to 5 tons' capacity, as in the case of the Waverley 5-ton chassis,

Fig. 8. Two-Motor Axle with Spur-Clear Drive, Commercial 2-Ton Truck

Fig. 7. The Commercial electric is an exception to this in that it
shows the successful employment of two motors on cars as small as
one-ton capacity. The rear axle of this car is a complete self-
contained unit, as will be seen upon referring to Fig. 8 illustrating
the drive of a 2-ton Commercial. The form of mounting employed
is clear in the illustration, while Fig. 9 shows the details of the gear
reduction between the motor and the driving wheel. This concern
also makes a four-wheel drive, which is employed on vehicles of 3| to
7 tons' capacity. On these machines, both front and rear axles are
alike. One of them is illustrated in Fig. 10, in which it will be noted
that the motor and the driving wheel are an integral unit pivoted in

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the axle to permit of utilizing all four wheels for steering. The speed
reduction in this instance is simply a double spur-gear train meshing
with an internal gear cut on a drum in the rear wheel.

Couple-Gear Truck Drive. A particularly ingenious example of
the ease and directness with which electricity lends itself to special

Fig. 9. View of Spur-Gear Reduction of Commercial Electric Drive

forms of construction is to be found in the drive of the Couple-Gear
truck, so called because all four wheels are not onlv driven bv electric

Fig- 10. Two-Motor Axle of Four- Wheel Drive of Commercial Heavy Trucks

motors but are utilized for steering purposes. These vehicles are
built as straight electrics, using a storage battery as the source of

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^ixrrent; and as gas-electric vehicles, a gasoline engine and generator
f <^ roiing the power plant, the remainder of the design and construc-
ts ion being the same in both cases. Fig. 11 illustrates the detail of
tlr*e axle design employed, each wheel being carried on a steering

Fig. 11. Couple-Gear Axle for Unit- Wheel Drive

spindle, and all four wheels coupled to act in unison, permitting the
car to turn in a very short radius. The parts shown on the right-
hand spindle in the illustration are the fields of the motor, the wind-

rig. 12. Dismounted Couple-Gear Truck Wheel, Showing Motor Parta

ings being just visible in the armature tunnel. They are made in
this form, as the motor is practically a part of the wheel.

The motor is built directly into the wheel, as will be apparent
from the illustration of a dismounted wheel shown in Fig. 12. The

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motor is of bipolar type, designed with flat fields in order that it may
fit within the wheel without unduly increasing its section, and is held
by its attachment to the axle. The wheel accordingly revolves about
the motor, being driven by the two small pinions which are noticeable
on opposite ends of the armature shaft and which mesh with the
circular racks attached to the periphery of the wheel. The brushes
are carried in a yoke bolted to the outer half of the field casting, so

\'<u. 1 i. Walker Ucctru- Cha^is, Showing Combined Motor Axle

that the removal of the latter makes everything' accessible. The
cables for the motor current are led through the hollow axle. Apart
from this feature and the employment of a four-wheel steer, the
vehicle itself follows more or less conventional lines.

Balanced Drive. The transmission on the Walker cars, known
as a "balanced drive", is another radical departure from current
practice in this respect. These cars are built in capacities ranging
from 7o0 to 7(KJ() pounds and have been in successful service for a

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number of years. As will be noted in Fig. 13, a single motor is
employed, and it is built practically as an integral part of the rear
axle, the housings of which form the fields. The armature of the
motor is at right angles to the driving wheels, and its shaft is extended
both ways to form the drive. At the outer ends, this shaft carries
small spur pinions which mesh with two large gears. The latter,

Fig. 14. Detail* of Walker Electric Wheel Drive

in turn, mesh with an internal gear bolted to the inner face of the steel
rims of the driving wheels themselves. The detail of this is made
plain in Fig. 14, showing one of the wheels with the outer protecting
disc removed. It will be apparent that this constitutes not only
an unusually compact motor unit and transmission, having the great
advantage of being always in direct line with its drive, but that it
likewise dispenses with a differential, as the wheels themselves are
balance gears.

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CURRENT AND CURRENT CONTROL
Battery Equipment. As the motors commonly employed are
wound to take current at 80 to 85 volts, the battery consists of 44
cells, divided into three or four groups of cells held in separate oak
boxes, or "trays", as they are termed, to facilitate handling. This
voltage is standard, regardless of the size of the vehicle, the latter
being compensated for by changing the capacity of the battery.
Thus, for light delivery wagons, each cell contains three positive and
four negative plates of medium size, giving an 85-ampere-hour dis-
charge capacity, while a 1000-pound wagon is equipped with a bat-
tery having nine-plate cells with a capacity of 112 ampere hours; a
2000-pound wagon, eleven-plate cells of larger dimensions, giving
140 ampere hours; and so on in accordance with the size of the
vehicle and the load it is designed to carry. Most electric vehicles
have the battery underslung, i.e., carried in a cradle supported from
the frame of the chassis. The cradle is enclosed in a battery box for
protection against mud and water and has hinged doors at the ends
through which the battery may be introduced or removed. By this
arrangement, the weight of the battery, which is the heaviest single
item in the entire construction, is distributed evenly between the
forward and rear wheels, which leaves the entire floor space of the
wagon available for the load. In special types, such as the G.V.
1000-pound worm-driven delivery wagon, the usual practice in the
pleasure-car method of carrying the battery under a hood forward is
followed. All the wiring between the battery, controller, and iftotor
is carried beneath the floor and is protected from injury by running
it through iron conduits.

Controller. In the case of delivery wagons and light trucks,
the controller itself is placed either beneath the seat or under the
footboards and is similar in construction to those employed on street
cars, but much smaller in size, owing to the low voltage and com-
paratively small amount of current to be handled. It is operated by
a small hand lever and usually provides four speeds ahead and two
reverse, all of which are obtainable by moving the same lever,
although a special lock, or catch, must first be operated before the
vehicle can be moved backward. This usually takes the form of a
pedal, or kick plate, which may be depressed with the heel and must
frequently be held down while reversing. When released, it auto-

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matically returns the controller to the ahead position, in order to
prevent the vehicle from being backed inadvertently.

Departures from the usual method of placing the controller are
to be found in some of the medium-capacity vehicles, such as the
Baker, in which the controller is located on the steering column just
below the footboards; in the Urban, it is placed in a special dash
compartment, the lever being on the steering wheel. This compart-
ment also contains the ampere-hour meter, a type of instrument
which records in watt hours the amount of power drawn from the
battery and, at the same time,
indicates the available amount
remaining at any time. Ampere-
hour meters are coming more and
more into general use on both
pleasure and commercial electrics,
and a detailed description of the
instrument and its use is given
in connection with electric pleas-
ure cars. In service, this dash
compartment is protected by an
aluminum plate through which
the dial of the meter appears. On
the Commercial, the controller is
mounted directly on the steering
column and is operated by a sec-
ond smaller wheel, Fig. 15. The
controller itself is thus above the
footboards, and by the removal

of the protective housing shown becomes very accessible. In cases
where it is necessary to provide for handling heavy currents, a
railway type of controller is employed.

A novel controller installation that gives instant accessibility is
found on the G.M.C., as shown in Fig. 16. The controller proper,
as well as all wiring terminals, fuses, and meters are mounted under
a short hood, the resistance being suspended just beneath the con-
troller, while the charging receptacle is below the center of the bumper.
This view illustrates the forward side of the dash, while Fig. 17 shows
the side facing the driver. The connection between the control lever

Fig. 15. Commercial Electric Controller on
Steering Column

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20 COMMERCIAL VEHICLES

over the steering wheel and the controller is through a shaft and
a bevel gearing, as shown in Fig. 16. In the illustrations, this lever is

Fig. 16. Controller Installation of G.M.C. Electric Delivery Wagon

at the neutral position, successive movement from this point forward
giving five speeds ahead and two reverse speeds backward. The

Fig. 17. Simple Control of G.M.C. Electric

G.V. control is equally compact, being mounted in a steel box form-
ing the driver's seat, as shown in Fig. 18. The safety switch and

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the plug connection for an inspection lamp are seen on the outside at
the left. Inside are, first, the switch connections, then the fuses, and,
next, the fingers of the controller. At the upper right hand (driver's
left) is the control lever, while just visible below the box is the
resistance.

Safety Devices. In view of the fact that the average driver of
an electric delivery wagon or a truck is either a graduate from the
reins or has had no experience in handling vehicles at all, it has
become customary to provide safety devices which, to a large extent,

Fig. lfS. Controller Box of G. V. Electric Delivery Wagon

prevent accidents that might otherwise result from this lack of
experience.

Cut-Out Switch Connected to Brake. The brake is usually inter-
connected with a cut-out switch which automatically shuts off the
power independently of the controller simply by the application of
the former. While the brakes are sufficiently powerful to stop the
machine even with the current on, forgetting to shut off the current
would either blow out the fuses or result disastrously to the motor.

Circuit- Breaker and Hand Switch. A circuit-breaker is provided
on some cars to obviate the necessity for frequent replacing of the
fuses, this being the usual practice in street railway and other electric
work. Frequently, a hand-operated cut-out switch is also installed

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22 COMMERCIAL VEHICLES

to permit of inspecting or working on the controller without the
necessity of disconnecting the battery, as a failure to do so where
no switch is provided is apt to result in painful burns, owing to the
large amount of current.

Charging Circuit- Breaker. Another safeguard is an automati-
cally operated circuit-breaker to protect the battery from being
overcharged. This is used in connection with the Sangamo ampere-
hour meter, which is described under the head of "Meters". Unlike
the Anderson device described previously, which can be employed
only where connection can be had to the field coils of the generator,
this circuit-breaker operates exactly the same as the circuit-breaker
in a generating station, which opens the line when an excess amount
of current passes through it, except that in this case its operation is
not controlled by the number of ampere turns on the circuit-breaker
itself, • but by a trip switch actuated by the ampere-hour meter when
its dial records that the battery is fully charged.

Devices to Prevent Accidental Starting or Tampering. Devices
are provided to prevent the accidental starting of the vehicle when
not anticipated by the driver; also to guard against tampering by
the ubiquitous small boy. On the G.V. 1000-pound worm-driven
delivery wagon, for example, the emergency brake cannot be locked
on except when the "running switch" is in either the neutral or the
charging position, and cannot be released until thrown into the run-
ning position. Moreover, this switch can be thrown to the running
position only when the controller is at the "off" point, or neutral
position. The interconnection of the brakes and the controller
"throw-off" allows the driver to use both hands for steering, in an
emergency and, at the same time, to cut off the power and apply
both brakes with his feet. This emergency-brake lock compels the
driver to turn off the current by throwing the running switch to
neutral when leaving the car; it also prevents the brake from being
released by an unauthorized person, as the driver can take the switch
handle with him. As the brake cannot be released until the switch
is thrown on, the driver is reminded of that fact. The running-
switch lock prevents the accidental starting of the vehicle, which
might happen if the controller had been tampered with during the
driver's absence, and if, upon his return, he threw the running switch
on without first looking at the controller handle.

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Brakes. Owing to the comparatively low speeds, the braking
equipment in the earlier designs usually consisted of a single set of
drums attached to the driving wheels. Against the inner faces of
these steel drums bronze shoes were expanded by means of a pedal
and the usual brake rigging beneath the car. As was the case in
practically all early chain-driven cars, the braking drums carried the
driving sprockets on their outer faces.

But in this, as in many other essentials, practice has been
improved along the lines followed in the gasoline car. It is now cus-
tomary to employ two sets of brakes, one for regular service and one
for emergencies. Usually, both sets of brakes are carried in drums
on the driving wheels, either side by side or concentrically, a friction
facing of asbestos on a woven-wire foundation being employed. In
some cases, the service brake operates on a drum carried on the
armature shaft of the motor.

Tires. While solid rubber tires are most generally employed,
they are not necessarily so, as pneumatic tires are to be preferred
where the merchandise to be carried is of a light or fragile nature
or where speed is one of the chief features of the delivery service.
They not only reduce the liability to breakage, but also lessen the
cost of maintaining the vehicle in repair. However, as there are
comparatively few branches of commercial service in which the pneu-
matic tire is economically practicable, its use is very limited. The
solid tires employed vary in size from two to four inches, and foj
weights in excess of the capacity ,of the latter, they are used in twin
form on the rear wheels.

SPECIAL FORMS OF THE ELECTRIC

Electric Tractors. The huge street-cleaning or garbage-removal
truck, shown in Fig. 19, is drawn by a 5-ton G.V. electric tractor,
the combination being along lines somewhat similar to the front-
driven electrics adopted by the Paris street-cleaning department for
the same purpose, except that the latter have a two-wheel tractor
and are fitted with a specially designed covered steel body. One use
of the electric tractor built along the lines just referred to is shown
by the Couple-Gear propelled steam fire engine, Fig. 20. Part of
the battery is carried on the frame and the remainder is suspended
beneath it, the power consisting of two Couple-Gear motor wheels

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24 COMMERCIAL VEHICLES

Fig. 19. Five-Ton O. V. Electric Tractor Hauling Garbage Wagon

mounted on steering spindles and operated by a street-railway type
of controller which will be noted at the left of the driver. The entire
power plant is a complete unit, which is bolted directly to the engine
without further alteration than the removal of its front truck.

Fig. 20. Couple-Gear Tractor Drawing Steam Fire Engine
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Industrial Trucks. One of the most important developments
of the past few years has been the widespread adoption of the so-called
industrial truck. In a broad sense, the term represents a classification
rather than a type, as there are several different types of chassis built
for this purpose. Probably the first of these to be placed in service
was the Lansden dock truck, designed for handling cargo on steam-
ship piers. In addition to this, there are baggage and mail trucks for
use in railway depots, also truck cranes and tractor trucks, and it will
be apparent that they are designed for service where no other form of
power than electricity would be either convenient or permitted. The
battery truck crane, the baggage truck, and the tractor trucks are
merely modifications of the simple freight truck, their functions vary-
ing somewhat in each case. The baggage truck has a field of its own
in the handling of baggage and mail, some being of the drop-frame and
double-platform type and others having the battery and mechanism
placed below the loading platform, which is made of railway-car
height.

The simple industrial, or freight, truck is built in sizes and capaci-
ties suitable for moving loads on piers, in freight sheds, warehouses,
factories, and industrial establishments generally. Its short wheel-
base permits it to pass through congested spaces, going backward or
forward with the same facility, while it is capable of ascending gradi-
ents of 10 to 25 per cent. On piers and at railway terminals it can
deliver its load on the deck of a vessel or in a box car. The capacity
of such trucks seldom exceeds 2000 pounds, this figure being found
the practical limit for trucks capable of the widest range of action.
The loading space of a truck of this capacity is 28 square feet, while
the total area required for movement is only 34 square feet, the
machine having an extreme width of 4 feet and an extreme length
of 8 feet, so that an industrial truck can be operated wherever a hand
truck can go, while the former will ascend grades impossible to the
latter.

Fig. 21 shows a standard G.V. 2000-pound industrial truck, of
which there are several hundred in use. Both the battery and the
driving mechanism are suspended below the platform, which has
rounded corners and is extended to protect the mechanism at every
point. Its speed on hard level surfaces is 7 miles per hour; its average
radius, 25 miles on one charge of the battery, the current consumption

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28 COMMERCIAL VEHICLES

for a full charge amounting to 6 to 8 kilowatt hours. For grades up
to 10 per cent, only one motor is employed. When equipped with
two motors, each rear wheel is driven by an individual motor geared
to a housed spur gear fastened to the w T heel. A spring-returned con-
troller is used, the operating lever returning to neutral when released
by the driver. The brake is also spring-operated and is normally set,
so that in order to run the car the driver must keep the brake pedal
depressed. A further safety precaution is an automatic cut-off

Fig. 21. G.V. One-Ton Industrial Truck Handling Freight

switch connected with the brake, so that in releasing the pedal of the
latter the power is cut off automatically. In addition to this pedal,
two operating handles are provided, one for the controller and the
other for steering, the truck being capable of turning around in a
7-foot radius. In general freight-shifting service, the hauls averaging
from 200 to 800 feet, each truck displaces from four to six men with
hand trucks. The efficiency of these trucks is frequently increased by
using them in connection with trailers and large numbers are employed
in factories for transporting material from one department to another.

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ELECTRIC TRUCKS
Classification. There is little, if any, difference in design between
delivery wagons and trucks, the frames, axles, wheels, springs, and
transmission simply being made heavier in proportion to the great
increase in load to be carried, while there is a corresponding difference
in the power of the motor or motors and in the size of the chains or
other essentials of the transmission. As already mentioned, some
makes, such as the Walker, adhere to the single-motor power plant
even in sizes up to 2 and 3J tons' capacity, and the G.V., Lansden,
Waverly, and G.M.C., up to 5 and 6 tons, on the score of increased
economy and higher efficiency, while others, such as the Commercial,
employ two motors on vehicles as small as the 4000-pound size and
four motors on larger trucks.

Next to the delivery wagon, in which electric power has scored a
great success, trucks of 2-ton and 3-ton capacity are the most com-
mon forms of electric vehicles — though the 5-ton size has come into
general use for brewery service — several hundred being run by brewers
in New York, while one St. Louis company has nearly a hundred.
Electric trucks of 6- and 7-ton capacity are also built. In order to
obtain the increase in load-carrying capacity, the size of the motor
must naturally be enlarged, with a corresponding increase in the power
consumption, which calls for a very much larger battery. In order
that the capacity of the battery may be sufficient to give the vehicle
a practical radius of travel on a single charge without unduly adding
to the weight, the speed is reduced, so that electric trucks of 2-ton
capacity usually have an average speed of 8 to 10 miles an hour;
3-ton trucks, 6 to 9 miles an hour; while 5-ton trucks seldom exceed
7 miles an hour.

Characteristics of Chassis. The electrics listed by the General
Vehicle Company afford an excellent example of a standard design
of chassis applied to cars ranging from 1000 pounds up to 5 tons'
capacity, the intermediate sizes being 2000 pounds, 2 tons, and 3£
tons. Naturally, the first two are delivery wagons and are capable
of traveling 45 miles on a single charge of the battery at a maximum
speed of 12 and 10 miles per hour, respectively. The 2-ton wagon,
while capable of the same mileage, has a maximum speed of but 9
miles per hour. This is further reduced to 8 miles per hour for the
3$-ton truck, which has a radius of 40 miles on a charge, while the

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28 COMMERCIAL VEHICLES

5-ton truck travels only 7 miles an hour as a maximum and has an
extreme radius of 35 miles on a charge. In every case, only a single

Fig. 22. Rear View of G.V. 4000-Pound Chassis

motor is used, and as the design in all other respects is also standard
for all sizes, a description of the 4000-pound wagon will suffice.

Fig. 23. General Electric Motor

With the exception of the use of a single-motor drive, a large
number of the parts employed are practically the same as those used

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COMMERCIAL VEHICLES 20

in other makes of electrics. The foundation of the entire car consists
of a pressed-steel frame, to which are directly riveted the cradle for

Fig. 24. Rear Axle of G.V. 2-Ton Truck

carrying the battery, the spring hangers, and the supports for the
countershaft bearings.

A view of the complete chassis will be found in Fig. 2.
The view is taken -from above and illustrates every essential except
the battery. At the rear are the semi-elliptic springs, the solid-steel
axle, artillery wheels with solid rubber tires and large driven sprockets,
driving chains, the single motor suspended from a transverse tubular
member on the frame, the enclosed silent-chain drive from the motor
to the countershaft, the wiring in conduits from the controller to the
motor, and the countershaft with its radius rods to equalize and
maintain its distance from the rear axle. These rods also serve to

Fig. 25. Front Axle of G.V. 2-Ton Truck

take the stresses of driving off the rear springs. Just in front of the
countershaft is the steel cradle for the battery trays; at the left, that
is, at the front of the truck, is the steering gear, forward axle, springs,
and wheels.

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30 COMMERCIAL VEHICLES

An excellent view of the entire bottom construction, which gives
a clear idea of the arrangement of the power and the drive, is shown
in Fig. 22, while the essentials comprising it are shown in detail in
Figs. 23, 24, and 25. Fig. 23 is a G.E. multipolar, ironclad motor.
Fig. 24 shows the rear axle, while the forward axle and its steering
attachments are shown in Fig. 25. A 44-cell storage battery furnishes
current at 85 volts, the motor being wound to operate economically
at this voltage. The battery is in sectional form, in crates of such
weight and size as to permit of easy removal or of replacement from
either side of the vehicle. It is so arranged that it may be recharged
without disturbing it; but, where two batteries are employed, a
charged set may be easily and quickly substituted for the exhausted
battery.

The controller is of the continuous-torque type which will per-
mit of changing the motor speeds by degrees without interrupting the
power between any of the steps. This gives a gradual and steady
acceleration, without the jerk and strain so detrimental to the life and
efficiency of every part of the vehicle. The motor is designed along
the lines which have proved so successful in street-railway work. It
has a very heavy shaft as well as a simple and durable brush rigging
and is wound to show not only a high efficiency but also a high capac-
ity for overload. The armature shaft, which is carried on annular
ball bearings that tend to greatly increase the efficiency of the motor
as a whole, is suspended on a transverse bar pivoted to the side mem-
bers of the frame forward of the rear axle. This pivoted suspension
keeps the motor shaft parallel with the countershaft throughout the
entire range of chain adjustment and permits the use of an efficient
silent-chain drive, which, as will be noticed in Fig. 2, is enclosed in
an aluminum housing.

The countershaft is housed in and is carried on four taper-roller
bearings inside the tube, the latter being held in self-aligning ball
sleeves in hangers riveted to the sides of the frame. The two short
driving shafts are connected by a spur differential and carry at their
outer ends small sprockets for the roller chains to drive the rear
wheels, the entire countershaft being a complete unit. It is driven by
a silent chain of ample width running over a small pinion on the motor
and over the gear of the differential. Altogether, this is a very effi-
cient form of truck.

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GASOLINE VEHICLES

GASOLINE DELIVERY WAGONS

Classification Limits. It will be found on a brief examination of
the subject that this is a far more comprehensive heading than would
appear at first sight, as it includes everything from the little three-
wheeler up to the type known as the "light truck", but which is, in
reality, also a delivery wagon with an open platform, or stake type of
body. The range of carrying capacity is from one to two hundred

Fig. 20. Autocar Two-Cylinder Delivery Wagon

pounds up to one ton, or slightly more, as many delivery wagons and
light trucks are built with a load capacity of 2500 pounds or even
3O00 pounds.

Autocar. The Autocar delivery wagon, Fig. 26, affords an excel-
lent example of a vehicle designed especially for the most severe
business conditions. The motor is of the two-cylinder, horizontal,
opposed, four-cycle type, the cylinder dimensions being 4f-inch bore
by 4J-inch stroke, and is rated at 18 horsepower. The crankshaft is
mounted on imported annular ball bearings, which not only add
greatly to the efficiency of the motor as a whole, but do away with the
attention necessary to adjust plain bearings. This construction,

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which is far more expensive than plain bearings, also reduces the
number of parts which are subject to damage should the driver
neglect to provide sufficient oil. The lubrication system is entirely
automatic in operation. Two flywheels are carried on the crankshaft,
the forward one having its blades cast staggered so as to set up a
strong current of air, thus eliminating the necessity of a belt- or gear-
driven fan, while the rear flywheel carries the clutch. The impor-
tance of providing ample weight in the balance wheel is something to
which insufficient attention has been devoted in the past, its influence
upon the starting ability and the smooth-running qualities of the
vehicle being extremely marked, especially where a two-cylinder motor
is employed. Both flywheels on the Autocar motor are counter-
weighted, and this, supplemented by a careful balance of all the
reciprocating parts, makes an extremely smooth- and quiet-running
motor with- unusual starting and grade-climbing ability for its size.

The crankcase is split horizontally into two sections, the lower
half carrying the cylinders, crankshaft, camshaft, and water pump,
while ths upper half carries the push-rod guides, the magneto, the
oiler, and a gear for driving the water pump. The magneto and
oiler are both driven through bevel gears and short shafts, reducing
the possibility of failure in these two highly important essentials —
ignition and lubrication — to a minimum. The upper section of the
crankcase is readily removable, carrying its parts with it and thus
giving access to the crankpin bearings without the necessity of
dismantling the motor. A Bosch magneto with a fixed firing point
is employed, thus taking this element of control out of the hands of
the driver. Lubrication is by a force-feed oiler delivering oil through
a sight feed to the crankcase, from which the pistons, crankpins.
and main bearings are lubricated by splash. Both the magneto and
the lubricator are simply attached to the crankcase by w T irig nuts
so that they may be removed without the aid of tools. A hydraulic
speed regulator, connected in the circulation circuit of the cooling
water, controls a throttle placed in the intake manifold between the
carburetor and the cylinders, limiting the speed of the motor to 1400
r.p.m. and that of the vehicle to 18 to 20 miles per hour.

A patented floating-ring clutch, which has been developed on the
same make of pleasure cars and used for a number of years, constitutes
the first step in the transmission. It consists of a bronze floating

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ring, lined with cork inserts on its inner face, and is mounted on four
keys on the inside of the rim of the rear flywheel, thus rotating with
the latter. Two cast-
iron rings, adapted to
clamp the bronze ring
when the clutch is en-
gaged, are mounted on ••
the clutchshaft which
extends into the trans-,
mission case. Engage-
ment is accomplished by FiR 2 ? - Autocar ^m^*«i™*™ F, » ati »« *"* Axl «
a sliding trunnion and four -toggle links, the motion of which is
checked by a dashpot and k plunger. This insures gradual automatic
action, entirely free from jerk, regardless of the care exercised by the

Fig. 2S. Rear Vii-w of Antomt IVIivcry Wnyn

driver. The addition of small springs to the flouting ring eliminates
all noise, whether the clutch be engaged or not.

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The transmission housing is all in one piece, except its cover plate,
and has been so designed that all the shafts and gears may be removed
without disturbing the housing itself. The shafts are large and are

Fig. 29. Autocar Engine and Transmission Mounted on Separate Sub-Frame

carried on adjustable roller bearings, while the gears have broad faces
and heavy teeth. Three speeds forward and one reverse, operating
progressively, are provided, lubrication being obtained by covering
the shafts and gears w T ith a bath of semi-fluid oil.

Fig. 30. Autocar Mrw-ine and Transmission — Plan View

Both front and rear axles have been designed especially to meet
the requirements of the heavy service imposed upon them in carrying
the load on solid rubber tires. The front axle is of the tubular type,

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with extra heavy yokes for the steering spindles, which are made
integral with the spring saddles. Adjustable roller bearings are
employed in the wheel hubs. The rear axle is of the full floating
type, with a double-gear reduction. A bevel pinion at the end of the
propeller shaft meshes with a large bevel gear on a short transverse
shaft, from which the drive is transmitted to the differential case by
means of a pair of substantial spur gears, the method of mounting
them being shown by Fig. 27. The complete axle, as well as the
spring suspension, the brakes, and other details are shown in the
rear view, Fig. 28.

One of the chief features of advantage on the Autocar delivery
wagon is the mounting of the complete motor and transmission,
hairing the rear axle, on an independent sub-frame, as shown in Figs.

Fig. 31. Plan View of White Delivery Wagon Chassis

29 and 30. An illustration of the complete chassis would show every
part of the power plant to be accessible by lifting the bonnet, while
the complete unit, as shown separately, may be removed from the
chassis and replaced by another. The rear view of the chassis,
Fig. 28, shows the relative location of all the essential parts, including
the gasoline tank, which is placed transversely on the main frame
directly under the driver's seat. The frame is of pressed steel,
perfectly rectangular and heavily reinforced. Two sets of brakes
act on drums attached to the driving wheels, while the suspension
consists of double-elliptic springs in the rear and semi-elliptic springs
placed forward directly under the motor.

White. This may be regarded as a representative standard
design, as will be evident from the photo of the chassis, Fig. 31 , show-

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36 COMMERCIAL VEHICLES

ing that it differs from heavier-capacity vehicles of the same make
only in being shaft-driven and having lighter dimensions. It is built
in 1500- and 3000-pound sizes, the chassis illustrated being of the
latter capacity. Single rear tires are usually fitted on the smaller
car, and pneumatics are frequently employed to take advantage of the
higher speed thus made possible, an example of this practice being
illustrated by Fig. 32. Apart from the difference in dimensions and
tire equipment, both sizes are the same, each being equipped with a
3|- by 5^-inch motor, the cylinders of which are cast in one piece,

Fig. 32. White Delivery Wagon with Light Top Body and Pneumatic Tires

with the intake and exhaust passages integral. This motor is rated
at 30 horsepower and fitted with a compression release for starting.
A single-nozzle water-jacketed carburetor supplied with hot air from
a jacket on the exhaust pipe, a high-tension magneto for ignition,
and a gear-driven centrifugal water pump comprise its auxiliaries.

GASOLINE TRUCKS

Load Efficiency Increases with Size. It will be apparent that
above the 2-ton size the load efficiency increases, as, once a certain
point is reached, additions to the weight caused by increasing the
dimensions of the load-carrying space and adding to the power of the
motor are disproportionately small as compared with the increase in

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load capacity. For example, one truck of 3-ton capacity has a chassis
weighing only 4500 pounds, which tips the scales at 5200 pounds
completely fitted, or "all on"; on the other hand, another chassis
for the same nominal carrying capacity, i.e., 3 tons, weighs 6000
pounds. However, as no standard for rating the load-carrying
capacity of gasoline trucks has ever been attempted, and one maker's
5-ton truck is sometimes no larger than the 3-ton truck of another,
it is often difficult to make comparisons that will be fair on a basis of
catalogue weights alone.

MOTOR DETAILS
Design

Both the design and construction of internal-combustion motors
for commercial use are along lines similar to those employed on
pleasure automobiles except as modified by the requirements of
the more severe service. This necessitates a higher factor of safety
throughout, such as increased provision for lubrication and cooling;
extra large bearing surfaces, which must be readily accessible for
adjustment, except, of course, where antifriction bearings are
employed; increased crankshaft dimensions; broad gear faces; and
a considerably increased weight of flywheel in order that the motor
may develop as high a torque as possible at low speeds. The greater
amount of weight in the rim of the flywheel also eliminates motor
vibration to a considerable extent and makes the engine run much
more smoothly. Such variations of design as are usual in the pleasure-
car motors are to be found in the commercial type; in fact, where a
manufacturer builds both types, the same lines are followed in each
case, the only practical difference being in the dimensions and speeds.
It will be necessary, accordingly, to refer to only a few of the more
representative makes.

Long Stroke, Low Speed. Generally speaking, a commercial
motor is of the long-stroke low-speed type, some idea of the propor-
tions being obtainable by the dimensions of the White and the
Pierce-Arrow motors for 5-ton trucks. The former has a 4J-inch
bore by a 6f-inch stroke, while the latter measures 4J by 6 inches.
Similar small variations in dimensions are to be noted in practically
every make, in conformity with the varying standards of compression
and volumetric requirements adopted by their designers. This will

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38 COMMERCIAL VEHICLES

be apparent by a comparison of a few makes, such as the Locomobile,
5 by 6 inches; G.V. and Mercedes, 4.25 by 5.9 inches; Peerless and
Kelly, 4 \ by 6 \ inches; Vulcan, 4f by b\ inches. No increase is made
in motor dimensions above the 5-ton size, the extra carrying capacity
being gained by higher gear reductions and lower speeds, the Vulcan
motor mentioned being employed on both the 5- and 7-ton sizes of
that make. These motors are variously rated at 35 to 40 horsepower.

Fig. 33. Peerless 5-Ton Motor, T-Head Type

viz, Vulcan, 36 horsepower; White, 40; Kelly, 38.3; Peerless, 32.4;
Pierce- Arrow, 38.

Causes of Variations in Ratings. The variation in the ratings
is due to a number of causes, although one of the chief reasons is the
differences in the practice followed, i.e., in some cases, the power
stated is the maximum indicated horsepower based on the dimensions

and worked out bv the S.A.E. formula of - - , in which D is the

2.o

bore, A r the number of cylinders, and 2.5 an arbitrary constant

derived from taking the speed characteristics of a large number of

motors and striking an average representing a piston speed of 1000

feet per minute. In other eases, it is the result of actual brake tests

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Vik. III. White lO-Hor^power Work-Type- Motor for .VTon Truck

Fig. 35. Pierce-Arrow Motor for 5-Ton Truck

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and is accordingly based on the maximum r.p.m. rate of the motor:
while in still others it is the power which the motor is capable of
developing at the speed at which it is controlled by the governor,
usually 800 to 1000 r.p.m., to give the best service from the truck of
the capacity for which it is designed. For instance, the rating of
the Kelly motor is based on a speed of 900 r.p.m., while that of the
Peerless, Fig. 33, of the same dimensions, is its indicated horsepower
figured according to the above formula. The White motor, Fig. 34,
is an example of the L-head type; while the Pierce-Arrow, Fig. 35,
like the Peerless already mentioned, is of the T-head type.

Accessories

Ignition. In every department of commercial-car practice, the
designer aims to make the operation of the machine as nearly auto-
matic as possible and to that extent to relieve the driver of any
opportunity to exercise his discretion. The usual practice is to
employ a magneto fitted with an automatic spark-timing device.
This operates on the principle of the centrifugal governor and is
controlled entirely by the speed of the motor, so that when the motor
is stopped the spark timing is fully retarded and there is no danger
from a "back-kick" as is the case where this precaution is inadvertently
overlooked. As the motor speed increases, the occurrence of the
spark in the cylinders is automatically advanced to correspond,
thus relieving the driver of this important function and preventing
the abuse of the motor in unskilled hands. The same slight differ-
ences in detail as found on the pleasure type are also found in the
ignition systems of commercial cars.

Carburetors. Carburetors also are the same both in principle
and construction as on the pleasure cars, except in instances where
they have been specially designed for commercial service, in which
case the modification applies to the construction. In view of the
very general custom in this country of leaving the design of auxiliaries
to the accessory manufacturer, the number of these instances is very
small, so that in the majority of cases the carburetor manufacturer
sells the same carburetor for either type of vehicle. To permit of the
efficient utilization of lower-grade fuels, ample provision is usually
made for heating the carburetor by a large warm-water jacket and a
supply of hot air taken from a collector located on the exhaust pipe.

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Cooling Systems. The so-called direct system, in which air is
relied upon to keep the cylinder walls of the motor at a temperature
that will permit of efficient operation without danger of seizing,
was never attempted on commercial vehicles except in the lighter
sizes. Most of these were light delivery wagons, although one make
of 3-ton trucks employed a blower system for several years. How-
ever, air as the cooling agent without an intermediary in the form of
a water circulation has been definitely abandoned on the commercial
car. Both the principles and the operation are the same as on pleas-
ure cars, due allowance being made for the more severe service by
increasing the size of the pump, the section of the cylinder jackets,
the area of radiating surface, and the diameter of the connections.
Radiator Construction. The radiator is the most vulnerable
part of the truck, and precautions are therefore taken to protect
it from injury. In order to be proof against the constant vibration
and jolting, the gilled-tube type of radiator is employed in the
majority of instances. Accidental damage is usually provided against
by extending the frame and equipping it with a bumper, and further
protection is sometimes afforded by mounting a heavy wire screen
in front of it. This is done more frequently on honeycomb, or
cellular, radiators, as they are liable to suffer severely when prodded
with the steel-shod pole of a horse-drawn truck, and are difficult
and expensive to repair. In the case of the gilled-tube type, only
those tubes actually struck are likely to be damaged and they will
frequently bend without rupture, while often nothing more serious
happens than the bending and derangement of the cooling fins
with which each tube is surrounded. These tubes are placed ver-
tically and, in the case of the Reo 2-ton truck radiator, Fig. 36,
are made demountable, so that a damaged tube may be easily replaced
in a short time without the necessity for making any soldered repairs.
It will be noted that each pair of tubes is held in place by a bolted
yoke, so that upon loosening the yoke they may be lifted out. This
illustration also clearly shows the flat copper tubes, which are placed
with their narrow edges facing the air current, as well as the copper
radiating fins attached to them. The upper and lower parts of the
radiator are hollow castings, which form tanks, the sides merely
providing a support and spacer for the tubes. The usual construction
consists of a removable tank, which forms the top and bottom

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chambers,, with a bank of gilled tubes having their ends expanded
and soldered into perforated plates, the solder playing an unim-
portant part, as such joints cannot be relied upon where there is
much vibration.

Unless properly provided against, one of the chief sources of
injury to the radiator arises out of the twisting of the frame under
torsional stresses. Flexible joints between the radiator and motor
are accordingly necessary to take care of relative movement, and it is

common practice, both
in this country and
abroad, to employ rubber
hose for this purpose.
By reason of the heavy
loads carried and the use
of solid tires, this precau-
tion is not sufficient to
guard the radiator
against the effects of
vibration and road
shocks, so that it is usu-
ally mounted on some
kind of spring suspension.
This spring suspension

Fi K . 30. Reo Demountable-Section Gilled-Tubc Radiator USUally Consists of a pair

of helical springs, one on
either side, so that the radiator has no solid connection with its sup-
port. In some instances, the radiator is hung on a pair of trunnions,
similar to a gun mounting, but this form, while providing ample
allowance for movement, does not cushion it against shocks. Still
another method consists in mounting the radiator on an extension
of the motor, the motor itself being carried on a three-point support,
so that the radiator and motor move together; but, unless provided
with some form of spring buffer between them, this type suffers
from the same disadvantage as the one just mentioned. Figs. 37
and 38 show some typical methods of radiator protection.

Fans. In every case, the radiator is supplemented by a fan
driven at high speed, and, in view of the slow travel of the heavier
trucks, the proper working of the cooling system depends upon the

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efficiency of the fan, since the speed of the vehicle cannot force a
strong draft of air through the radiator as it does in a touring
car. Thus, the fan is a very important part of the cooling system
on a slow-moving vehicle, as it
must provide an ample draft, no
matter how low the road speed
may be, otherwise the engine is
liable to heat beyond the point
where the oil begins to lose its
lubricating qualities. An ineffi-
cient fan allows excessive heat-
ing every time it is necessary to
climb a long hill.

Circulating Apparatus. In
the majority^of cases, the cooling

Fig. 37. White Radiator Mounting, Provid-
ing Spring Cushioning and Relative
Niovement through Clevises

water is circulated by a pump on commercial-car motors, though
many heavy trucks, such as the Kelly-Springfield, have thermosiphon
circulation. This pump is of the centrifugal type and is capable
of delivering a much greater volume of water than are those employed
on pleasure-car motors of corresponding power, owing to the reduced
road speeds of trucks. These pumps vary more or less in design,
but are based almost without exception on the centrifugal principle,
as the latter is the only one which will permit of a thermosiphon
circulation through it in case the impeller ceases to revolve. A
stoppage of the gear type of pump also stops the circulation at once.
Lubrication. Granting that an excess can be prevented from
reaching the combustion chambers of the cylinders, it is axiomatic
that the power plant of a motor
truck cannot have too much oil.
In commercial service, this de-
mands upon the lubricating sys-
tem are quite as severe as they
are upon the cooling system, and
the failure of one usually involves
the failure of the other in a short
time. Hence, a greater amount
of oil must be provided and every precaution taken to insure its
reaching the bearings. Except for the increase in the quantity of

Fig. 38.

Spring Hangers Combined with
Front Hanger Bracket

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44 COMMERCIAL VEHICLES

lubricant, this does not differ in any way from the requirements of
the pleasure car. Consequently, the'systems employed are practically
the same in both cases. The White lubrication system shown in
Fig. 39 illustrates a typical sight -feed system.

Motor Governors

Of the two chief evils that beset the motor truck in the hands
of the untrained driver — speeding and overloading — the former is
the more destructive, as the driver who will overload his truck will
also run at excessive speeds, and, with a heavy load, this is severe
punishment for the entire mechanism. The practice became so
common in the early days of the motor truck — nearly all drivers

Fig. 39. Sight-FtMxl (Drop) Lubricating System as Uned on Whit© Trucks

then being graduates from the pleasure-car field — that it has now
become customary to govern the speed of the motor. The governor
itself is usually sealed to prevent its being tampered with by the driver.
General Characteristics. The most generally accepted type is
that of the usual centrifugal governor attached directly to the motor
and operating a butterfly valve in the intake manifold between the
regular carburetor throttle and the valve ports. Owing to the high
motor speeds and the slight amount of movement necessary, the gover-
nor is very small and compact, so that it will frequently be found incor-
porated in the crankcase at the end of the camshaft. A variation
from this is a drive taken from an outside auxiliary, such as the mag-
neto shaft or water-pump shaft. In either case, the speed of the

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governor is always directly proportional to that of the motor itself
and bears no relation to that of the vehicle. This is a disadvantage
at times, as in pulling through a heavy road on low speed when the
maximum power of which the motor is capable is required.

Controlling Car Speed. An improvement on this practice has

been the adoption of a vehicle "speed controller" which, while acting

on the motor itself in the same manner as the usual motor governor,

is controlled directly by the speed of the car and bears no relation to

that of the engine. With this type, the motor is free to run at any

speed at which the hand-operated throttle will supply it w T ith fuel,

so long as the speed of travel does not exceed that for which the

governor, or controller, is set. So far as the motor is concerned, it is

not directly governed and may be speeded up to any extent necessary

to pull the car through heavy going or out of a ditch, as the controller

does not come into action while the car is moving slowly. Practically,

the only disadvantage of this type is the fact that it does not prevent

the motor from racing, as does the former, when the load is suddenly

removed, with the throttle open. The vehicle speed controller is

driven either from one of the front wheels or from a shaft of the

transmission, as its operation depends entirely upon the speed of

the car. In addition to the centrifugal method of speed control, the

hydraulic principle is also employed. It will be apparent that as

the motor speed increases the circulation of the water, as driven

by the pump, does likewise, and there is a corresponding rise in

pressure in the cooling circulation. This rise in pressure is utilized

to act on a large diaphragm connected with a plunger attached

to a butterfly valve. A description of some of the governors in use

will make clear the method of taking advantage of the different

principles of operation.

Centrifugal Type. In Fig. 40 is illustrated a typical centrifugal
governor designed for attachment to one of the auxiliary shafts, as
will be noted by the driving gears at the bottom. As the revolving
weights tend to spread against the compression of the helical spring
surrounding the spindle on which they revolve, they push up a yoke
to which a shaft directly connected with the throttle valve is attached.
As in the case of the steam engine, this valve is entirely independent
of the hand-operated valve which may thus be left all the way open.
The details of construction of the Pierce governor are shown by

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the sectional view, Fig. 41, in which the weights are at the right.
As the triangular weights open under the centrifugal force generated,
they push the rod forward, and, as this rod has a rack cut on it

Seel ion of Governor
ond Drwiny Geary

r frorr Carburetor
Intake Manifold Section

Voire Cfperotinq
Mechanism

Fig. 40. Sectional Diagrams of Centrifugal Type of Governor

that meshes with a pinion on the butterfly valve, this action tends
to close the valve. A spring keeps this rod pressed against the
spindle on which the weights are mounted, but is not connected with
the spindle in any way. As is true of all governors in this service,

Fig. 41. Sectional View of Pierce Centrifugal Motor Governor

a speed adjustment and a method of sealing it against tampering
are provided.

Hydraulic Type. An example of the hydraulic type of governor
is shown in section in Fig. 42, while the application of this form of
governor is illustrated by the Reo 2-ton truck motor, Fig. 43. As

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will be seen in the section, this type consists of a water chamber,
diaphragm, spring, and operating lever; the operating mechanism

Fik- J2. Hydraulic Type of Governor

being combined with the
governor proper results in
a simple and compact
unit which requires only
one connection. This
connection is led from the
circulating system on the
cold-water side, as will be
noted in Fig. 43, in order
to bring it close to the
pump. As the speed of
the pump increases, the
pressure increases, and
the diaphragm is forced
down against the spring,
carrying with it the lever
operating the valve

■VI. Hydraulic Governor as Installed on Reo 2-Ton
Truck Motor

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48 COMMERCIAL VEHICLES 1

through a rack and a pinion. As the pressure decreases, the spring
returns the diaphragm, and with it the valve, to its normal position.
The water chamber, operating-lever housing, and the spring-retaining
plug are sealed so that the adjustment cannot be varied without
disturbing one of these seals. In this, as well as in the centrifugal
type where the adjustment is effected by altering the tension of a
spring, it will be obvious that the spring could readily be screwed
up so tightly that no speed of which the motor was capable would
have any effect on the governor, thus practically cutting out its
action altogether.

POWER TRANSMISSION DETAILS
Clutch and Transmission

Clutches. Cone Type. A comparison of the specifications of a
number of representative makes of trucks reveals a variation in
clutch design about equivalent to what would be found on an equal
number of pleasure cars, except that a greater number of instances of
the leather-faced cone occur in the trucks. This is the oldest type
employed on the automobile and is likewise the simplest in construc-
tion, which probably accounts for its more general retention in the
commercial field. What is termed the direct conical type, in wliich
the leather-faced cone engages by moving forward into the corre-
sponding wedge-shaped recess of the flywheel, is in more general use
than the indirect, or internal, cone in which the male member moves
backward into engagement. An example of the latter type is found
on the Peerless trucks, while the Garford, Kelly, Vulcan, Mais, and
Pierce are representative of the former. In the case of the Pierce,
the cone operates in an oil bath, the others running dry, as is more
often the case.

Multiple-Dine Type. The Packard and Autocar in this country
and the De Dion in France have long been fitted with a three-plate
type, the Albion (British) having a single-plate form of clutch in the
heavier sizes. Multiple-disc clutches are found on the Locomobile,
the Mack, and the Reo, and other American makes.

Transmission. Owing to the great reduction in speed necessary
between the motor and the driving wheels, transmission plays a
more important part on the commercial vehicle than it does on the
pleasure car. On the Latter, its services can be dispensed with in an

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emergency, as the car can be started on the direct drive in case of
accident to the intermediate speeds, but this would manifestly be
impossible on a heavily loaded truck. In this connection, it is to be
noted that the term "transmission" has come to signify the "change-
speed gearset" alone, doubtless owing to the awkwardness of the latter
appellation, and does not apply to the transmission of the power
from the motor to the rear or front wheels or to all four, as the case
may be.

Sliding-Gear Type. In the majority of instances, the sliding-gear
type of transmission is employed for commercial work, in which the
gears are actually slid into engagement with each other to effect
the various ratios of driving and driven members. This type is

Fig. 44. Type of Transmission Employed on White Shaft-Driven Trucks

practically universal on the pleasure car, so that only a brief reference
to it is necessary here. On almost all except the lighter vehicles, it
provides four forward speeds, the others having but three speeds and
reverse. Fig. 44 shows the White transmission as employed with
a shaft drive. Owing to the controlling connections being absent,
this has been inadvertently photographed with both the first, or
lowest speed, and the direct, or highest speed, engaged. The large
gear at the left, shown in engagement with its corresponding gear on
the layshaft, gives the first speed. By moving it forward until the
gear just ahead, with which it is integral, meshes with the next gear
to the right on the layshaft, the second speed is obtained. Moving
the single gear at the right back until it meshes with the right-hand
gear of the pair on the layshaft gives third speed. For fourth speed,

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50 COMMERCIAL VEHICLES

or direct drive, this same gear is moved forward, its forward face
being cut in the form of a dog clutch that engages a similar gear
permanently attached to the clutchshaft. This is unusual, as the
dog clutch is generally formed of a smaller diameter extension on
the hub of the direct-drive gear. The two gears at the extreme right-
hand end are permanently engaged and serve to drive the layshaft.
By moving the largest gear to the extreme left, the reverse is engaged,
this being effected through an intermediate pinion, or idler, part of
which is just visible below the main shaft at that point. The moving
members slide on splines cut on the main shaft, the sliding being
sometimes effected by making the main shaft of square section.

Fig. 4o. Peerless Transmission and Countershaft

A similar transmission, combined with a bevel drive and spur-
gear differential on a jackshaft for side-chain final drive, is that of the
Peerless, Fig. 4"). This is shown engaged on the direct drive, so
the dog clutch is not visible. The material used in the housing is
usually aluminum, sometimes cast iron, and, in the case of the
Locomobile, manganese bronze. Annular ball bearings are employed
in many instances, the bearings themselves being apparent in the
White transmission and their mountings in the Peerless. Taper
roller bearings are also employed for the same purpose. Operation
is almost invariably by the selective method, the gear lever being
shifted across through a gate to pick up one or* the other of the
sliding members shown. The control lever of the White, which is
mounted directly on the transmission housing, is shown in Fig. 46.
This lever is more often mounted at the side in a fixture also carrv-

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ing the emergency-brake lever, as on the Pierce. On this truck,
only three forward speeds are provided.

Mack Transmiss-ioti. The Mack transmission, Fig. 47, is a
selectively operated type in which the gears of the various speeds
are always in mesh, small clutches being designed to slide in either
direction on the squared main shaft, engaging the particular speed
desired. These clutches are practically small gears which mesh

Fig. 46. Completely Assembled White Transmission, Showing
Control Lever

with internal-gear members attached to the driving members.
They will be noted lying between the driving gears on the main shaft,
in the illustration. The gear housing in this case is of phosphor bronze.
Use of "Dog" Clutches. A variation of the Mack type of trans-
mission employs what are known as "dog" clutches, probably from
the fact that they apparently bite into one another, being cut with
a comparatively small number of heavy teeth on their end faces.
These teeth, if they can be properly so-called, are of heavy section

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and are cut with an easy angle which insures ready engagement
This will be noted in the direct-drive engagement of the White gear-
set. The dog-clutch type of gearset has been employed more in
Great Britain than in this country. Its great advantages are that
the driving gears are constantly in mesh and that the dog clutches
can be engaged without particular attention being paid to the speed
at which the two shafts are revolving, as is necessary with the sliding-
gear type. The details of a transmission of this kind, as well as

Fig. 47. Mack Transmission Used on Manhattan Trucks

of the method of operation, are clearly shown in Fig. 48, which is a
Cotta transmission designed for use on worm-driven trucks. As
shown in the illustration, the first, or low, speed is engaged, the
clutch on the layshaft at the lower right-hand corner being in mesh
with its counterpart on the large, or low-speed, gear. The clutch-
shaft being at the right-hand end of the gear box, as shown, the drive
is then through the pinion on it, the large gear below, with which
it is in mesh, and then through the layshaft and the pair of gears
at the left-hand end, these gears being fastened to their respective

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shafts. The other gears, with the exception of the clutchshaft
pinion previously mentioned, are free to rotate on their shafts and
are permanently in mesh. However, the male members of the
individual clutches, while free to slide on the shafts, must turn with
them, so that when engaged they "pick up" the various gears cor-
responding to the different speeds.

Silent-Chain Transmission. Another form of transmission,
which has been used to a greater or less extent abroad, but which
has found little favor here, is the silent-chain type. This is along
similar lines to the Mack transmission illustrated, except that roller
chains take the place of the permanently meshed gears, dog clutches
being engaged to pick up the latter according to the speed desired.

Final Drive
Until a few years ago, there was a sharp line of demarcation
between the pleasure car and the commercial vehicle where the

Fijr. 48. Cotta Individual (Dog) Clutch Transmission
Designed for Worm-Driven Trucks

important final drive was concerned. Practically all pleasure cars
were shaft-driven, and, to the same extent, commercial cars were
chain-driven. The tendency that has manifested itself in the interim
makes it apparent that the history made in the development of the
pleasure car is apt to repeat itself in commercial-car development.
In other words, chain-driven trucks were largely in the majority
a few years ago, but the recent advances made in live-axle construction
have had a marked effect and their adoption has now reached such
a scale that, barring something unforeseen, the chain on the truck
will soon disappear as it has from the touring car.

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Classification. As at present employed, there are four general
classes of final drive on commercial cars. In the order of their age
and present comparative importance, these are: first, the double
side-chain from a centrally located countershaft carrying the differ-
ential and the bevel drive, and usually combined with the gearset, or
transmission, so called; second, the worm drive, which differs from
the bevel-gear type only by the substitution of a worm and a worm
wheel for the bevel gear and the pinion; third, the double-reduction
live axle, in which a bevel-gear drive is employed in connection with
a second reduction in speed through the spur gears; fourth, the so-
called internal-drive rear axle, in which the first reduction is through
the conventional bevel gear and the second is by means of a small
spur pinion meshing with an internal gear cut on the inner face of a
drum attached to the driving wheel. It may occasion some surprise
to note in this connection that the worm drive is mentioned as being
second in point of seniority, and further that no mention is made of
the standard bevel-gear live axle. In the first place, the use of the
worm on automobiles dates back to its employment on the Lan-
chester pleasure cars in 1898 and its adoption on the Dennis busses
in London in 1903, on which it has been regularly used ever since.
No mention is made of the standard bevel-gear axle here, since the
latter is only adapted for use on light cars. The higher speeds at
which these vehicles run do not necessitate the employment of
extremely high reduction ratios, so that a live axle of this type may be
employed without having to make the bevel gear of a size that would
seriously reduce road clearance, on the one hand; or a bevel pinion
that would exceed the mechanical limitations of this form of drive,
on the other. It is rarely employed, however, on vehicles of more
than 1£ tons' capacity, and the ease with which the entire speed
reduction necessary may be carried out in a single step by means of
a worm gear will doubtless make the straight bevel type obsolete
on commercial vehicles within the next few years.

Side-Chain Drive. Until the introduction in this country, at a
comparatively recent date, of the worm drive, some form of double-
reduction gearing has been used on all heavy motor trucks. The
form most commonly used has been the double side-chain final drive,
in which the primary gear reduction is obtained by means of a bevel
gear driving the jackshaft and a secondary reduction in the chains

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and sprockets. This type of drive, utilizing roller chains, has been
used on nearly all heavy motor trucks since the inception of the com-
mercial vehicle. With but one or two exceptions, on all these
trucks of American manufacture no attempt has been made to house
the chains in, and they run exposed to dirt, mud, and water.

Standard Types. A typical American side-chain drive for trucks
of medium capacity is shown in Fig. 49, which illustrates a Timken
unit. Except for the provision of brakes and sprockets at its outer
ends instead of wheels, the countershaft, or jackshaft, is practically

Fijr. 49. Timken Standard Jaekshaft for Side-Chain Drive

a bevel-gear live axle. The rear axle is what is known as a "dead"
axle in that it has no moving parts other than the wheels which
revolve on bearings mounted on it. The two wheels are kept at a
predetermined distance apart, and their parallelism is preserved by
two distance, or radius, rods. A little consideration will make it plain
that the thrust of repulsion against the ground of the driving wheels
must be taken up on the vehicle before the latter can move, other-
wise the rear axle would tend to travel forward independently until
checked by the springs, which would then take the driving effort.

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This is frequently done on pleasure cars, and makes a flexible powr-
transmission which is easy on the mechansim and the tires, but which
is not practical with the heavy loads handled on trucks. Hence, the
radius rods are employed to transmit this strain to the frame o*
the car, but, at the same time, they must provide for a certain amount
of relative movement in both a vertical as well as a horizontal plane,
besides affording a certain amount of flexibility.

Radius and Tonjue Rods. Fig. 50, which represents a well-
worked-out radius-rod design, illustrates how these various require-
ments are met. Starting at the right-hand end of the rod which i>
attached to the rear axle, it will be seen that this design consists of
a connecting-rod type of bearing that permits movement in a vertical
plane, as this bearing is held on a tubular section of the axle an<)

esta

Fig. ">0. Flexible I'nivorsiilly Jointed Radius Rod for Double Sid^-Ohuin Drivo

is kept well lubricated. Just forward of the bearing is a heavy spindle
which pivots the rest of the roil on the rear bearing, so that ample
provision is made for lateral movement. The rod proper is in two
parts held together by the compression of a heavy helical spring, which
relieves the mechanism and tires of the initial thrust of starting, and
also prevents shocks to the rear axle reaching the frame via the
radius rod. Further provision for movement in a vertical plane is
made by the attachment of the forward end of the rod to the frame,
which forms a pivoted yoke. The threaded portion and the locked
collar, noticed at the forward end, allow for adjustment in the length
of the rod, this adjustment being provided for in the spring rod
by the nut shown inside the yoke at the forward end. On shaft-
driven cars, a torque rod is employed to take this thrust and also
to take up the twisting effort, or "torque," of the propeller shaft.

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Speed Reduction. The rear axle proper is simply a drop forging
of I-beam section representing the strongest and lightest cross-
section for a beam. It is forged integral with the pads, or saddles, for
attaching the springs and is machined to receive the wheel bearings
and the bearings of the radius rods which complete its construction.
The driving sprockets are bolted to the pressed-steel or cast-steel
brake drums and the latter are in turn bolted to the wood artillery
wheels. On trucks of two to seven tons' capacity, the speed reduc-
tion between the motor and the rear wheels ranges all the way from 7
to 1 to 14 or 15 to 1. The first step in the reduction is carried out in

Fig. M. Hear of Packard 5-Ton Cha.s.sis, Showing Size of Driving Sprockets

the bevel-gear drive of the countershaft and rarely exceeds 4 or 5
to 1 , as the use of a larger bevel would involve the use of a cumber-
some and weighty housing. The remaining reduction is accom-
plished by the difference in the driving and driven sprockets. How
great this second reduction may be can be seen from Fig. 51, which
is a rear view of a standard design of side-chain-driven heavy truck,
the Packard. A study of this illustration will make clear several of
the details of axle, spring, brake, and radius-rod construction
described in previous paragraphs.

Worm Drive. The worm gear was tried tentatively on steam
traction engines in England as early as 1850, but it was not until

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1898, when it was applied to the driving of the Lanchester car, that
it was seriously taken up for this purpose. The Lanchester worm is
a peculiar variation of the more familiar Hindley type and is placed
under the wheel to insure lubrication. An illustration of this worm
gear will be found in the section devoted to the transmission of
electric pleasure vehicles, as worm gears of this type are imported
from England for use on the Detroit electric cars. The first rear-
axle motor-truck drive of the worm type was a 3^-ton Dennis bus

V\ii. ")2. Phantom View of Pierce Worm-Driven Rear Axle

and quite a number of worm-driven Dennis busses have been in
service in London for several years. Dennis was also the first to
running in London. This was first put in service in 1903 and, though
its introduction met with considerable opposition, it proved a success,
mount the worm over the wheel, producing the so-called "overhead"
type, which feature also came in for much criticism owing to its
alleged failure to provide lubrication. It will be perfectly obvious
that with the worm-wheel housing only partly full of oil this criticism
would be unfounded, as the wheel acts as an excellent conveyor
to carry the oil up to the worm. Eight years' use in London without
failure of lubrication bears out this statement.

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Development. The London General Omnibus Company was the
first to design and manufacture on a large scale a new type of worm-
gear axle in which the worm gear w r as mounted on a separate assem-
bly. This design has superseded others until now, with some modi-
fication, it is accepted practfce. The worm and the wheel are
mounted in a very rigid block and, with their bearings, housings,
etc., form a complete unenclosed transmission unit, as seen in
Fig. 52, which is a phantom view of the worm gear employed on the

Fig. "ui. ChasMis of Pierce ">-Ton Worm-Driven Truck

Pierce trucks, the makers of the latter having been the pioneers
in introducing this type into the United States. This unit is dropped
into the bowl-shaped rear-axle housing and bolted in place. This
mounting lends itself readily to accurate machining, every part
being open and easily accessible. This is also true of the unit as
a whole where inspection, adjustment, and repair are concerned.
This housing is of heavy construction and, as it is rigid, prevents
road shocks or stresses, other than those coming through the driving

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axles, from disturbing the alignment of the worm gear. The housings
of the driving shafts, or axles, are tubular, and the shafts themselves
are assembled through the tubes into the squared sockets in the
differential. This makes a very accessible assembly as, by pulling
out the driving axles and disconnecting the universal joint, the worm
unit can be lifted out of its housing. The socket, with several
keyways in it extending forward from the worm proper, is for the
reception of the splined end of the propeller shaft from the gearset.
This keyed socket is the slip end of the rear universal joint in the
shaft line and is designed to prevent relative movement of rear axle
and of gear set from imposing excessive stresses on the propeller shaft.

The driving thrust and the torque are taken on a short heavy
torque rod, which will be noted extending forward from the rear-
axle housing just below the universal joint. This is a heavy drop
forging and, as will be clear, is mounted on a heavy spindle at the
axle housing, allowing for movement in a horizontal plane; while at
its forward end, which is made in the form of a yoke, it is carried
on a horizontal pin permitting a vertical movement to compensate
for variations in the vertical distance between the axle and frame
caused by the compression and recoil of the springs. Its location
is made clear in the chassis view, Fig. 53.

Fig. f>4 shows the form of mounting adopted by the Timken
Company for the David Brown type of worm drive which they
manufacture. This is the same as that employed on the Pierce
trucks, but both the method of mounting and the bearings differ.
The Timken Company use their own taper roller bearings, while the
Pierce Company use annular ball bearings. The worm is of the
so-called straight type, meaning that it is of uniform diameter
throughout its length as distinguished from the "hourglass" type.

Standard Types of Worm Gears. In the straight type, the worm
is cylindrical through its entire length, and the worm wheel into
which it meshes is concave. In the hourglass type, both worm and
worm wheel are concave. The advantage claimed for the latter
form is the greater area of engagement, thus spreading the driving
strain over a greater number of teeth and reducing the pressure on
the surface of both. On this type, however, there is only one position
in which the worm and the worm wheel can be located with respect
to each other in order to take advantage of this greater area of con-

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tact, while on the straight type it is necessary only to locate the worm
correctly, with respect to the worm wheel, in one direction, since the
worm is cylindrical and uniform in diameter throughout its entire
length. The straight type is therefore much less liable to damage
through misalignment. With the hourglass type, a slight misplace-
ment in any direction is liable to prove fatal, so that the chances of
trouble in practical operation are greatly reduced in the straight type.
Efficiency of Worm Gears. In an elaborate test of three differ-
ent types of worm gears (by types in this connection being meant

Fig. 54. David Brown Type of Worm Gear as Mounted on Timken Axle

differences in tooth form and pitch) made at the Brown and Sharpe
plant to determine which form was best adapted to automobile use,
efficiencies ranging from 90.2 to 95.5 were obtained on the first speed,
91.3 to 93.4 per cent on the second speed, and 90.1 to 97.0 per cent
on the direct drive. The results obtained with a bevel-gear-drive
test made for comparison were 91.4 to 9(3.6 per cent on first speed,
94.5 to 99.3 on second, and 94.0 to 99.2 on direct drive. So far as
the life of the worm is concerned, mileage records obtained on com-
mercial cars range from 40,000 to 110,000 miles, the lower figure

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being considered only fair for a well-made straight type of worm;
while, on pleasure cars, three years of constant service was not
thought at all unusual.

Double-Reduction Live Axle. As sufficient drop in speed can-
not, be had with a bevel gear through a single reduction without
making the driven bevel gear of impracticable proportions, thus
involving excessive weight in the rear-axle housing and a dangerous
lack of clearance between the latter and the ground, an intermediate
spur reduction is introduced just forward of the bevel gears. One
method of accomplishing this is illustrated by Fig. 55, which shows
the extra speed reduction combined in the same housing as the
differential and the bevel drive, an extra cover plate making it
accessible. It will be noted that helical-cut gears are employed

Fijr. ."i;V White Differential, Showing Second-Reduction Gear

instead of the straight-spur type, this form of tooth giving greater
bearing surface, closer engagement, i.e., less backlash, or lost motion,
between the gears and far less noise in running. Another form of
double-reduction axle is the special type developed on the Autocar
delivery wagon and illustrated in connection with the description of
that vehicle.

Internal Gear-Driven Axle. The internal gear-driven type of
axle is another form of final drive that has been introduced in this
country after a long and successful record abroad. Like the worm
gear, it aspires to the honor of replacing the side chains and, like that
form, also has already made considerable progress in this direction.
In principle, this form of drive consists of making the driving axles in-
dependent of, and external to, the rear axle proper, which, in this case,

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is of the "dead" type, usually a solid section, such as a square or an
I-beam forging. Its function is merely to carry the weight of the
car, although it also is made to serve both as a support and as a rein-
forcement for the live axle. In the case of the Mercedes (German)
trucks, on which it has been used since 1900, the driving axle is
placed forward of the dead axle. At their outer ends, the shafts of
the latter carry small spur pinions which mesh with large internal
gears cut on rings attached to drums on the rear wheels. One of
these wheels and the driving pinion on the end of the live shaft are
illustrated in Fig. 56, which shows this construction as carried out
on an American-built replica of the German truck in question.

This same form of axle has been employed also for a number of
years in Paris by the builders of the De Dion cars for their commer-
cial types, chiefly busses. In this case, the live axle is carried above

Fig. 56. Mercedes (German) Internal Gear Drive. Showing Principle of Action and
Assembled Rear Wheel l

its support. More than a hundred of these busses have been in
service in New York for several years and, as more are ordered
from time to time to meet the increasing requirements, it must be
concluded that they have been satisfactory. The builders of the Mais
trucks were doubtless the pioneers in the commercial use of this form
of axle in this country, and the Mais internal gear-driven rear axle is
probably the form in which this type is most generally used. In this
case, the driving axle is placed forward of the dead axle. Upon com-
paring the size of the driving pinion at the rear wheel with the internal
gear, it will be apparent that a very large gear reduction is conven-
iently obtainable by this method without in any way interfering with
the road clearance of the vehicle. The first reduction consists, of
course, in every case, of the conventional bevel-gear drive, but, as will
be noted from the part sectional views of the Torbensen and Garford

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types of internal gear-driven axles, as shown in Figs. 57 and 58, there
is very little reduction between the bevel pinion and its gear. This
decreases the amount of leverage the pinion has to exert and conse-

Torbensen Internal Gear-Driven Kr.ir Axle

quently decreases the tooth pressure in proportion. In the Torben-
sen axle, the live member, or countershaft, is placed to the rear of the
I-beam supporting member, while in the Garford this is reversed. On
the Jeffery "Quad", it is placed directly over the wheel support, as

Fig. 58. Garford Internal Gear-Driven Rear Axle

shown by Fig. 59, which illustrates the driving pinion and the wheel
with its internal gear. As this truck steers, drives, and brakes on all
four wheels, a universal joint is placed directly behind the pinion.
Fig. 60 shows the wheel and its gear ready for mounting. A some-

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what similar design is found on the Christie front-drive tractor for fire
apparatus, with the added distinction that on this machine only the
rim of the driving wheel revolves and is carried on a ball bearing
which is practically the size of the wheel itself. On the Jeffery, the
wheel revolves on the two taper roller bearings shown.

Differential Lock. The function of the differential, balance gear,
or compensating gear, as it is variously called, is naturally the same
on the commercial vehicle as it is on the pleasure car, i.e., that of
permitting one wheel to run free in rounding a turn so that it may
travel the greater distance represented by the outside circle in the

same time that the inner

takes to traverse its orbit ;

but the differential has

the unfortunate draw-
back of not permitting

any f power to reach one

of the driving wheels in

case it is held while the

other is free. This fre-
quently occurs where the

truck settles into a ditch

or extra deep rut in a

soft road, leaving the

other wheel more or less

in the air. Under such

conditions the entire

power goes tO the free Fig. 59. Jeffery Rear-Axle Driving Mechanism

. . - . . . and Bearings

wheel, making the prob-
lem of extricating the machine from this predicament much more
difficult. To overcome this disadvantage of the balance gear, it
is customary to provide a differential lock. One form of this lock
is illustrated in Fig. 61. On the right-hand side a four-jaw clutch is
keyed to the drive shaft, but is left free to slide into mesh with its
corresponding member on the differential housing to permit of lock-
ing the differential gears. This clutch is operated through a suitable
linkage from the driver's seat. By locking the differential, the sunken
wheel will pull itself out if the truck is capable of exerting the
necessary power.

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Front Drives. Early Development. One of the earliest applica-
tions of power proposed for road locomotion was the attachment of
a self-contained power unit to existing horse-drawn vehicles, and a
number of different types of such units were built in Europe in the
early days of the industry. For some reason, none of them developed
to the point of a commercial success. The front-wheel drive, which
seems to have been discarded almost entirely for some years, has
recently come to the fore again and has been developed very success-
fully for fire apparatus, on which both mechanical and electrical
methods of transmission have been utilized.

Fig. »'»<). .leffrry Whorl with Intcriml dear Heady for Mounting on Axle

Electric Front Drive. The electric front drive has been utilized
in numerous lines of business, more particularly for brew r ery and
municipal service, for several years; the Couple-Gear type of electric
motor wheel, previously described in the section on the transmission
of power on electric cars, was employed for this purpose. In some
instances, a single power wheel is used to haul a dump cart or similar
slow-moving vehicle; or a unit, comprising a storage battery, con-
troller, steering gear, axle, and two of these power w ? heels, is per-
manently coupled to a truck in place of the axle and wheels used
when drawn bv horses.

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The power to drive these motors may be supplied by the current
from a storage battery or from a gasoline-electric generator. The

Fig. 01. Bevel-Driven Commercial-Car Axle Fitted with Differential Loek

Fig. 02. Electric Front Drive Using Couple-Gear Motor Wheels

dynamo supplies the power directly to the wheel motors through a
three-point controller, there being no other intermediate electric

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68 COMMERCIAL VEHICLES

member. This controller is fitted with two forward speeds and a
single reverse, the speed and amount of power utilized being con-
trolled chiefly by means of the spark lever and the throttle of the
gasoline motor in the conventional manner. Fig. 62 illustrates a fire
engine gasoline-electric tractor using Couple-Gear drive.

Four-Wheel Drives. To meet the requirements of military
service, a truck must be able to travel "wherever a team of mules can
haul a load". Consequently, like that useful quadruped, it must
be equipped with power-transmitting members at all four points of
contact with the ground. While the conventional type of truck
with one or the other of the standard forms of transmission driving
only two rear wheels has proved eminently satisfactory for service
wherever a solid roadbed or its equivalent is to be found, it is of
little use off the beaten track. Ditches, soft ground, sand, and mud,
which .do not even embarrass the army mule or, for that matter, the
average team of farm horses, render the. average motor truck abso-
lutely helpless. To be able to extricate itself from bogs and ditches,
it is necessary to be able to "git up and git" on all fours.

To take advantage to the full extent of this form of transmission,
the majority of four-wheel-driven cars both drive and steer through
all the wheels. Accomplishing this presents no particular mechani-
cal difficulties. Three forms of drive have been developed for this
purpose; one in which the power is transmitted through bevel gears
mounted on the steering knuckle, while a second employs the internal-
gear type of drive using universal joints on the driving shafts just
back of the wheels. The third type drives directly to the hubs
of the wheels through hollow steering knuckles. This last type
presents the simplest layout and was one of the first to be developed
in this country on a commercial scale, having been built for several
years by the Four Wheel Drive Automobile Company.

This transmission is a simple modification of the three-speed
individual-clutch type transmitting the power through a broad silent
chain to a parallel shaft placed at the left to clear the engine. This
can be seen more clearly in the photograph of the chassis, Fig. 63.
This chain also serves as the first reduction in the speed, the second
being through the conventional form of bevel gears at the rear and
front axles. Each of these bevel-gear drives incorporates a differ-
ential for balancing the tractive effort at the wheels, while a third

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differential centrally placed on the parallel driving shaft balances the
amount- of power transmitted to each pair of wheels. This third
differential is built in the large sprocket of the silent-chain drive and
is provided with a locking device controlled by the driver. A brake

Fig. 03. Chusiiist of Fdur-Whrel Drive Triu-k

drum is mounted on the parallel shaft on either side of the main
differential. These transmission brakes are for regular service, the
emergency brakes being mounted in drums on the rear wheels.

Fig. 04. Chassia of Jeffery "Quad", Showing Four-Whi-t'l Drivr

Owing to their location, the former retard all four wheels simul-
taneously. There are, of course, four universal joints. Steering is
accomplished by means of the front wheels only, so that the rear
axle is of the conventional full-floating construction.

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Jeffery "Quad". This truck is representative of the second
class, or internal gear-driven type mentioned, and has been devel-
oped particularly to meet' the United States Army requirements.
The motor is a four-cylinder block-cast type with L-hedd cylinders
rated at 32 horsepower and is fitted with duplex ignition, i.e., using

Courtesy of Jlorxtiess Age

two sets of spark plugs simultaneously. The motor is offset to the
right side of the frame and mounted on a three-point suspension,
as shown by the plan view of the chassis, Fig. 64. The drive is
by shaft to a centrally placed four-speed selectively operated gearset
of the sliding-gear type, but the latter differs from the conventional

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form of this type of gearset in that it has no direct drive. The pro-
peller shafts are gear driven from the layshaft of the transmission,
this construction bringing the forward one sufficiently to one side to
clear the motor. Three differentials are employed, one on each axle
and one in the gear box, all being of the Wayne gearless type. Both
axles are "dead" and are fitted with steering knuckles. The trans-
verse driving shafts at either end are placed above the axles and
springs and have universal joints just inside of the wheels and directly
over their steering pivots, as shown by the sectional view, Fig. 65.
The driving pinion is supported from the steering knuckles between
two taper roller bearings and drives an internal gear mounted in the
enlarged wheel hub. Bolted to this large hub and the wheel itself is

Fig. 00. Chassis of Jcffcry "Quad"

a pressed-steel drum for an external brake, a dust-excluding felt
packing being fitted between the drum and the gear ring. The
ability of the four-wheel drive to extricate itself from heavy mud and
sand with the same amount of power is due to the tendency of the
front wheels to climb over obstacles and, at the same time, assist in
the propulsion of the weight. Enclosed wheels are employed to cut
down the resistance, Fig. 60.

Electric Transmission
Advantages. The practice of utilizing electricity for power dis-
tribution in manufacturing plants was already well established before
the advent of the automobile on a commercial scale, and attempts
were made at an early day to utilize its advantages for transmitting

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€50

the power on the latter. Despite the numerous difficulties met with
at the outset in the application of the sliding-gear transmission, the
employment of electricity has never become as general as its advan-
tages would appearto warrant. A great amount of experimental work,
how r ever, has been done, and numerous different systems evolved.
Probably the only example of the consistent employment of electric
transmission at the present date is to be found in its use on gasoline-
electric-railway motor cars, of which quite a number are in service.
As the limitation of weight, one of the most important factors to be
considered on the automobile, is lacking in this application, it can

hardly be said to represent an
/ exact parallel.
■'I One of the chief advan-

tages of the employment of
electric transmission is the
possibility of running the
gasoline motor constantly at
its normal speed, at which it
develops its rated output
most economically and with a
minimum wear. The sharp
contrast between the speed
variations required of the gas-
oline motor employed with a
mechanical transmission and
with one of the electrical type
is shown by the curves in
Fig. 67. With the electric transmission, the gasoline motor speed
remains constant from the time of starting right up to 50 miles
an hour.

Several Systems. To those familar with electric practice it
will be plain that several methods of utilizing electricity for the
transmission of the power on an automobile are available. In general,
however, they may be divided roughly into three divisions. The
first of these is simply a replica of that commonly employed in manu-
facturing plants, i.e., mechanical energy as produced by an engine
is converted into electrical power, transmitted to an electric motor
at a distance, and there reconverted into mechanical energy. This

?J 30

Miles per Hour

Fig. 07. Curves Showing Variations of Engine
Speed for Gasoline-Electric Transmission

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double conversion naturally entails a loss of efficiency; but, in manu-
facturing practice, this is considerably less than where the power is
directly transmitted from the engine to the tool at which it is to be
used, and the efficiency increases with an increase in the distance
between the two.

The second system involves the conversion of mechanical into
chemical energy in the storage battery, from which the current is
drawn to operate electric motors in the usual way, Fig. 68. This is
really a self-contained electric in that it carries its own charging plant,
with the further advantage, how r ever, that the excess capacity of the
generator is always available for driving the vehicle. Or, to put it

Fig. C8. Couple-Gear Gasoline-Electric System

the other way around, the greater part of the current from the gasoline
motor electric-generator unit is employed for running the car, and
the excess current utilized for charging the storage battery, which
is then said to be "floated on the line."

The third system is based on the principle employed in the cradle
type of electric dynamometer, in which an electric generator is so
mounted that its field may revolve in response to the drag exerted
on it by the armature, this tendency being counteracted by a balance
lever attached to the field. By means of weights placed on this
lever, the effort exerted may be accurately weighed, and the power
developed by the prime mover driving the generator may be calcu-
lated within close limits.

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74 COMMERCIAL VEHICLES

DETAILS OF CHASSIS AND RUNNING GEAR
Springs

The problem of providing a form of spring suspension that will
not be overstiff when the car is empty and still provide sufficient hold-
ing powers to withstand rough road work with a full load, which the
designer of the touring car has had to face, is aggravated a hundred-
fold on heavy trucks. Between the "load" and "no load" points
of the pleasure car, there is a comparatively small range. When a
touring car weighing 4000 pounds, all on, has its full load of seven
passengers .averaging 150 pounds each, their combined weight
represents only 25 per cent of the weight of the vehicle itself, but
when a 5-ton truck, weighing slightly over five tons when empty — say
11,000 pounds — receives its full load of five tons plus anywhere from
10,000 to 14,000 pounds, the increase, instead of being from to 25

per cent, is from to 100
per cent plus. There is
also the far greater tend-
ency to side sway, owing
to the height at which
the load is ordinarily
carried.

Semi-Elliptic Usual

Fig. 69. Principle of the Compensating Spring Tvn*» A a it normitc

Support Employed on Heavy Trucks * jP e - ^ s ll P ermilb

keeping the center of
gravity down, gives less recoil under heavy shock, and is less subject
to lateral stresses, the flat semi-elliptic type of spring is almost
universally employed on commercial vehicles, from a delivery wagon
up to a 7-ton truck. By delivery wagon in this connection is meant
the type specially designed for commercial service and not the con-
verted touring-car type in which pleasure-car standards remain
unaltered, and the high three-quarter elliptic spring at the rear
is not uncommon.

It will be apparent, however, that no form of spring suspension
would be sufficient in itself to cover such an extended range of loading
as that mentioned and still give even a fair approximation to efficiency
at either extreme. Maximum carrying ability is the chief thing to
be provided, and using springs that will do this alone would be an
easy matter; but the problem is to guard against the maximum

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stresses to which the springs will be subjected under heavy loads and
still have a suspension that will prevent the motor and driving
mechanism of the truck from being pounded to pieces when the
vehicle is running without a load. To achieve this, it is customary to
employ rocking shackles at one end and some form of sliding, or com-
pensating, support at the other, although in numerous instances the
springs are shackled at both ends in the same manner. As the driving
strain is practically always taken on radius, or distance, rods in the
ease of side-chain-driven cars, and on torque rods on cars of the shaft-
driven type, there is ample altitude for variation in this respect.

Principle of Compensating Support. The sketch, Fig. 69, illus-
trates the principle upon which all compensating supports for the
springs is bas^d. Of course, this applies only to the rear- wheel springs,
which are usually called upon to bear anywhere from 60 to 85 per
cent of the useful load. The front springs are usually pinned to
the dropped dumb ends of the frame forward and shackled to brackets
at their rear ends. The front end of a rear spring is shown by the
illustration. Given a suspension sufficiently stiff to withstand the
maximum load of which the truck is capable, it will be apparent
that when empty the body will be lifted and the sliding end of the
spring will be against the right-hand end of the support. The spring
is then under its minimum compression and will respond more readily
to shock.

Brakes
Usual Types. In as much as the greater loads carried far more
than offset the lower speeds at which commercial cars travel as com-
pared with the pleasure type, there can be no comparison of the
braking requirements of the two. This is particularly the case in as
much as the greatest strain does not come on the brakes because of
the infrequent necessity for stopping suddenly but on account of
their continued use in holding the loaded truck back on long hills.
Commercial-car brake design naturally varies with the type of vehicle
and likewise with its carrying capacity. On light delivery wagons,
the type employed is the same as used on touring cars, viz, internal-
expanding and external-contracting asbestos-fabric-lined shoes in
pressed-steel drums on the rear wheels. In some instances, the
practice, usually confined to the higher-priced pleasure cars, of placing
the two sets of brakes side by side so that they contact on the same

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drum and can be enclosed against the entry of dirt and water, is also
found. An example of the first type mentioned is shown in Fig. 70,
which illustrates a Timken worm-driven rear axle. The brakes on
the Reo chassis are shown in Fig. 71.

Braking All Wheels. Considerable discussion has arisen from
time to time regarding the advisability of braking on all four wheels;

Fig. 70. Timken Worm-Driven Rcar'Axle, Showing Brakes

but, prior to the advent of the four-wheel drive, this was tried in only
a comparatively few instances. In addition to providing greater
retarding power, the advantage of eliminating the tendency to skid
has also been attributed to the front-wheel brake. When all four

Fig. 71. Brake Detail, Reo 2-Ton Chassis

wheels are driven, brakes are applied to all simultaneously, the brak-
ing effort at each wheel being equalized by a compensating device.
On the Jeffery "Quad", these brakes are applied directly to the
wheels themselves and consist of a simple and well-worked-out
internal-expanding cam-actuated type, as shown by Fig. 72.

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COMMERCIAL VEHICLES 77

TRAILERS
Utilizing Excess Power. Trucks, like all other motor vehicles,
must necessarily be equipped with power plants capable of success-
fully meeting exceptionally severe conditions imposed by heavy
grades and by muddy, sandy, and snowy road surfaces, as well as
the normally easy grade and road conditions encountered by the
average truck during a very large proportion of its service. Hence,
there is a large reserve power-plant capacity idle for a great part of
the time. From the economic standpoint, it is a wasteful condition
for a truck with sufficient power to handle a ten-ton load on smooth

Fi*. 72.

Internal Expanding Cam-Actuated Type of Brake
Employed on the Jeffery '"Quad"

level roads to be restricted to the five-ton load which its structural
parts permit. This applies proportionately to all sizes of commercial
vehicles, from the very lightest up, and it accounts for the widespread
use to which trailers are being put.

Two-Wheel Types. For light- and medium-capacity service,
trailers can be made with only two wheels, thus keeping the wheel-
base of the double unit down and permitting of much higher speeds.
Trailers designed for use in connection with the lightest types of
delivery wagons, such as the Ford, or for the thousands of ex-touring
cars that are spending the second period of their existence in a com-
mercial r6le, usually carry a load of about 400 pounds. They are

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made to fit any standard make of automobile, a special bracket
being fitted to the rear of the frame of the car. Connection is made
by means of a tongue fitted with a swiveling pin and locked with a
thumb nut, so that the trailer may be attached or detached quickly
without using tools; the pin in question, together with the fact that
the trailer has only a single axle, allows for universal relative move-
ment between it and the towing car.

Four-Wheel Types. It is in the employment of what is prac-
tically a second truck, where its carrying capacity is concerned, that
the use of the trailer shows the greatest operating economy, and

FiR. 73. Troy Trailer for Motor Trucks

specially designed vehicles have been developed for this purpose.
The builders of the Troy wagons have evolved a special type of
trailer for the motor truck, as shown in Fig. 7.J.

Troy Trailer. It will be noted upon referring to the illustra-
tion, Fig. 73, previously mentioned, that the construction of the
Troy trailer is along very similar lines to those generally followed in
motor-truck construction. In fact, the trailer is practically a motor
truck without power and, as it is subjected to even heavier loading
and more severe strains than the latter, is built accordingly.

Both sets of wheels are designed to steer and are controlled by
the drawbars at each end of the trailer, the cross-connecting rod of

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the steering gear being attached to the under side of the drawbar
near its rear end. As the drawbar follows its towing truck around
corners, it also serves to swerve the front wheels of the trailer in the
same direction.

GASOLINE-DRIVEN TRACTION ENGINES

Greatest Field of Usefulness. Under this head falls a type of
machine which might be thought of as hardly coming within the
category of the commercial vehicle at all; but it represents an
extremely important branch which is just beginning to come into its
own and which, in the course of the next ten years or so, is destined
to prove a powerful factor in the elimination of the horse from many
classes of work now entirely monopolized by animal traction. Thus
far, haulage has formed only a comparatively small part of the work
of the gasoline traction engine and probably will not be generally
used for this purpose for some time to come. So far, its greatest
value has been in the carrying out of purely agricultural operations
on the large scale demanded by modern farming.

MECHANICAL DETAILS

Motor Design. Students of automobile engineering will recall
that the first attempts at automobile design in this country consisted
of nothing more than the adaptation of the ordinary stationary
engine to a running gear, and, further, that it was the dogged adher-
ence to this abortive combination that did so much to keep the
American automobile so far behind its European competitors in
the first years of the last decade.

The early agricultural tractors were likewise little more than
stationary engines of the horizontal type, mounted on a running
gear suited to the needs of the machine. The design was not as
poor a one for the purpose as was the case with the automobile, since
the conditions of service are totally different. Speeds are neces-
sarily very low, as plows or other tools cannot be handled properly
at a rate of travel in excess of a few miles an hour, while weight is a
desideratum rather than otherwise, in order to obtain the tremendous
tractive power needed to start and haul loads involving such a
great drawbar pull as is required to break a number of furrows in
hard soil.

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The practice of simply mounting a stationary engine on wheels,
which characterized early agricultural tractor design, has been prac-
tically abandoned and in its place has come a tendency to adopt the
automobile motor pretty much as it stands. Between these two
extremes are found motors which have been specially designed for
this form of service and which accordingly reflect the trend that
future developments are apt to take better than does either of the
others. Not that some of the automobile types of motors have not
been specially built for the purpose, which is probably the case in
most instances where they are used ; but it is to be questioned whether

Fig. 74. Seeor Kerosene Engine of Runiely Tractors

the light, high-speed type of motor is the best form of power plant
for such heavy, slow-moving machines.

Rumely Kerosene Motor. The agricultural tractor, to be gener-
ally adopted, must be capable of operating on a cheap and universally
obtainable fuel. At present, the only fuel that fills this requirement
is kerosene. Gasoline cannot be shipped on passenger steamers,
while railway freight on it is so high for long hauls as to make it
almost prohibitive in some parts of this country, notably in the
states of the great western plains; hence, most tractor motors are
fitted to use kerosene, including those used on the Rumely tractors.

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These motors are built in two sizes. The smaller size is a single-
cylinder 15-horse power unit, while the larger is a two-cylinder,
the constructional details of the last named being made plain by the
phantom view, Fig. 74. They operate on the Secor-Higgins principle,

Fig. 75. Details of Transmission, Sanison Tractor

which, in brief, is that of mixing water directly with the fuel, the
amount being regulated automatically in accordance with the load.
At the moment of explosion in the cylinder, the water is evaporated
and dissociated into its elements — hydrogen and oxygen. As the

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piston advances and the temperature drops, some of it is converted
into steam and liberates its heat, thus maintaining the pressure over a
longer proportion of the stroke, so that the engine develops a high
mean effective pressure on a comparatively low initial compression.
In addition to facilitating the combustion of the non-volatile fuel,
the nascent oxygen liberated has a high affinity for carbon and
materially assists in keeping the cylinders clean, while hydrogen
has a fuel value and is highly explosive when mixed with the proper
proportion of oxygen, so that it also assists in the quick and thorough
combustion of the kerosene.

Multi-Cylinder Motors. As already mentioned, these motors
follow the standards which have become familiar in automobile motor
design. They are usually of the four-cylinder vertical type, and
their construction and auxiliaries are practically identical with those
ordinarily employed on automobiles. In fact, the builders of the
British Daimler tractors employ the same Knight sleeve-valve engine
on these machines that they do on their high-priced pleasure cars.
The four-cylinder motor employed on the Samson tractor is shown
incidentally in Fig. 75, this illustration being chiefly intended to
reveal the details of the type of transmission employed.

Transmission. In this essential, a radical departure from auto-
mobile practice must naturally be followed, in view of the very low
speeds— usually not exceeding 2 to 2\ miles per hour for plowing — and
the tremendous tractive effort that must be exerted in hauling a
gang plow through heavy wet soil; consequently, it would be out of
the question to build the transmission in the form of a small gear
box, as is done on automobiles. While motors of the automobile
type are employed, their speed is usually very much lower; the motor
of the Samson tractor, for example, running at 525 to 575 r.p.m.
Still, to give the two forward speeds of 2 and 4 miles an hour, it is
evident that there must be a great reduction between the motor and
the driving wheels, particularly as the wheels are very large and
make comparatively few revolutions per mile. A double-drum
expanding friction clutch is built in the large bevel gears to form
the first step in the transmission, a small spur pinion on the same
shaft as the large bevels meshing with a large spur gear on a trans-
verse shaft. The latter carries two fixed gears, w r hile a sliding pair
is mounted on a parallel shaft just forward of it. When the left-

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hand one of these is meshed with the left-hand fixed gear, the tractor
drives at 2 miles an hour through still another speed reduction
between the second transverse shaft and the rear axle. By meshing
the right-hand gears, the higher speed is obtained. It will be noted
that there are four different steps in the speed reduction between the
motor and the rear axle and that the gears and shafts are of large
dimensions.

TYPES

Rumely. The Rumely tractor, shown in Fig. 76, is a close
approach to what may be regarded as standard practice in this field,

Fig. 76. Rumely Kerosene Engine Tractor

so far as its construction details are concerned. It takes but a glance
to recognize the influence of the steam traction engine and the steam
road roller of American design. One of these machines, which hauls
a gang plow turning eight furrows, is shown in Fig. 77.

International. The International tractor is practically nothing
more than one of the stationary engines made by this company,
mounted on the platform of a heavy, four-wheeled truck, Fig. 78.
The engine in question is of the single-cylinder long-stroke type, with
the valves in the head, the exhaust valve being mechanically operated,
while the inlet valve is automatic. The governor, as is customary in
stationary practice, is of the hit-and-miss type acting on the exhaust

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valve. In governors of this class, centrifugal force is taken advantage
of to make the exhaust^valve rod hit or miss the valve tappet, opening
the latter or allowing it to remain open, according to the speed and

Fig. 77. Kerosene Tractor Hauling Heavy Gang Plow

Fig. 78. Gang Plow and Gasoline Motor Tractor in Heavy Soil

the requirements of the load. As the automatic inlet valve depends
upon atmospheric pressure for its operation, it cannot open unless
the exhaust valve has closed on the stroke just preceding, so that no

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fuel enters the combustion chamber except when an explosion is
necessary. As the governor is also usually designed to trip the
igniter mechanism out of action at the same time, such engines are
very economical of both fuel and electric current. The cylinder is
of large bore, and a low compression is employed as compared with
automobile motor practice, two huge flywheels being utilized to give
the engine a smooth-running balance. The engine is cooled by
means of a modified form of water tank placed forward. This
tank is provided with a large wire^gauze screen with sloping sides,
over which the hot water is sprayed immediately on leaving the
water jacket; the water is then collected in the tank below and
circulated.

The drive wheels are entirely of metal, having a 50-inch diameter
and an 18-inch face; they have heavy lugs bolted to the tires to
provide ample traction, even on soft ground. Two friction clutches
are employed, a large one for the forward speeds and a smaller one
for the reverse. The drive is through two sets of pinions and large
gears, a sliding pinion on the crankshaft of the engine driving a large
differential gear on a countershaft carrying two pinions at its outer
ends, which engage large gears on the road wheels. Reverse is
obtained by shifting a lever which throws the large clutch out of
engagement and engages the small one driving an intermediate gear.
The same lever gives both the forward and reverse speeds, while a
foot lever applies a band brake that operates on the differential.
The foregoing serves to describe the small-size International
tractor, which is fitted with a 15-horsepower single-cylinder engine,
although it generally covers the construction of the larger sizes also.
Hart-Parr. The Hart-Parr tractor, which has achieved con-
siderable success, was one of the first to depart from the practice
of employing the ordinary stationary engine as its motive power.
As will be seen from the illustration, Fig. 79, the engine is of the two-
cylinder horizontal type, the cylinders being placed beside each
other and having all the valve mechanism in the head, which makes
it very accessible. The crankshaft has the two throws placed 180
degrees apart, so that the heavy pistons are always moving in oppo-
site directions. This gives an excellent mechanical balance and
accounts for the single flywheel of greatly reduced size. The use of
an auxiliary exhaust valve, or port, uncovered by the piston just before

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86 COMMERCIAL VEHICLES

the end of its outward travel on the power stroke, is also a feature

of this engine and insures cool running under the heaviest loads.

An original and ingenious system of oil cooling is employed,

making it unnecessary to take any precautions to prevent freezing in

Fig. 79. Motor of Hart-Parr Traction Engine

Fig. Si). Hart- Parr Traction Engine

cold weather. As will be seen from the illustration of the complete
Hart-Parr machine, Fig. 80, this system consists of a special type of
radiator mounted on the forward end of the platform. This radiator

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is formed of a number of thin corrugated sections covered by a
conical hood and a short stack. The supply of oil is circulated
through these sections of the radiator and through the jackets of
the cylinders by means of a centrifugal pump mounted directly on
one of the cylinders. The exhaust from the engine is led into the
hood over the radiator, and in the upper faces of the exhaust pipes
under the hood are drilled a large number of small holes, causing
the exhaust gases to be discharged upward in numerous fine jets,
which not only act as a muffler, but also set up a strong draft of

Fig. 81. Samson 3- Wheel "Sieve-Grip" Tractor

air through the radiator. As the oil never reaches a temperature
sufficiently high to boil it and there is therefore no waste, the original
supply should last as long as the engine, barring accidents. The
engine is capable of delivering 45 horsepower, according to the
usual rating, but as the machine is intended to displace 22 draft
horses, the tractor is given a nominal rating of the latter figure.
Samson. In contrast with this, the Samson, w r hich is built on
the Pacific Coast, represents a much closer approach to a three-
w r heel automobile or at least to an automobile tractor. Apart from

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its motor and transmission, which have already been referred to,
this machine is distinguished by the use of what is termed sieve-
grip driving wheels. These will be noted more in detail in
Fig. 75, from which it will be plain that they are in reality skeleton
wheels, the treads of which consist of series of angle bars riveted to
their supports in a staggered relation to one another where the two
wheels are concerned, thus giving the maximum traction. One of
these tractors is shown in service in Fig. SI.

Johnson. Fig. 82 illustrates a tractor of this type in service —
plowing an orange grove — and shows that it differs radically from
either of the foregoing. Like the Samson, it is a three-wheeler;
but there the resemblance between the two ends. The engine is

Fig. 82. Johnson Agricultural Tractor Plowing an Orange Grove

placed horizontally and drives through side chains and sprockets,
which accounts for a large part of the speed reduction necessary.
Instead of depending upon the natural movement of the air to
assist in cooling the radiator, the latter is carried in a housing which
contains a high-speed fan and which provides the necessary draft.
Auto-Tractor. As the time is already at hand when even a
greater proportion of the farming population boasts of automobiles
than city dwellers can be credited with, this tractor has been so
designed as to enable the farmer to use his car for actual farm work
in addition to its other services. The tractor accordingly consists
simply of a long steel frame, a pair of standard steel tractor wheels
fitted with a gear drive, and a standard automobile radiator, as will

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t>e seen in Fig. 83. The only modification required on the auto-
mobile itself is the fitting of a pair of small spur gears to the rear
wheels. The car is backed up over the tractor frame, and ropes

Fig. 83. Auto-Tractor Ready for Attachment

attached to the rear of the tractor are then passed around the hubs
of the rear-wheel gears mentioned. By running the car in reverse,
it hauls itself up the incline of the frame until the rear axle rests in
bearings provided for it. At this point, the wheel pinions mesh

Fig. 84. Method of Mounting and Attaching an Automobile to the Auto-Tractor

with large spur gears of almost the same diameter as the tractor
driving wheels. The front end of the tractor frame is then lifted
and made fast to the forward end of the car frame, the connections
of the extra radiator on the tractor are made with the cooling system

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of the car, and the automobile is ready to run as a tractor. Fig. 84
shows the car hauling itself into place on the tractor frame. When
attached to the tractor, the automobile motor may also be utilized
as a stationary engine.

In addition to the speeds available on the automobile, the
tractor gearing also provides two speeds which permit the machine to
travel at 2 or 4 miles per hour. The power is taken from the hub
gears on the automobile close' to the center of the axle instead of
from the tire; and, as the weight of the car is entirely removed from
the rear axle and there are no road shocks, the most injurious fea-
tures of ordinary automobile operation disappear. The gearing is so
designed that the car is run on high speed entirely, even when start-
ing under load, although the intermediate speeds may be resorted to
in case of extra heavy pulls. This means that when the tractor is
plowing at the rate of two miles per hour, the automobile engine is
running at its normal speed of 800 to 1000 r.p.m., at which speed it
is designed to give its best efficiency and run constantly without
strain. The use of one of these tractors in an Oregon orchard is said
to show a reduction from $3.40 per acre per year with teams to
$1.20 per acre per year with the machine, the cost per acre for each
cultivation with the machine being only 24 cents.

Holt Caterpillar Tractor. For agricultural operations in alluvial
lands, reclaimed swamps, and rice fields, or other ground so soft that
the wheel type would become mired, the so-called caterpillar tractor
has been developed. Tractors of this type have been in successful
operation in various parts of the world for a number of years. They
are built in two sizes, 30- and GO-horsepower. Fig. 85 shows one
of the smaller size and makes the appropriateness of the title apparent.
Apart from the variation in dimensions, the only difference between
the two is the provision of a forward steering truck on the large
tractor. From an engineering point of view, the Holt tractor is
of more than usual interest, as it is the only form of locomotion not
involving the use of wheels in contact with the ground.

As its name indicates, the tractor literally crawls over the
ground by means of blunt-toothed endless chains. This must not
be taken to signify that its speed is simply a crawl, as the tractor
illustrated hauls a gang plow at the rate of 2\ miles an hour, plowing
speeds for tractors generally being from 2 to 2^ miles an hour, regard-
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less of type. The motor is a four-cylinder vertical gasoline engine of
special design, the cylinders being cast independently with separable
heads. The valves are placed in these heads and operated by
rocker arms from a single camshaft. To provide the maximum
accessibility, the crankcase is of practically the same height as the
cylinders and is provided with large handholes through which the
pistons can be withdrawn; in fact, the crankshaft can be taken out
without disturbing the cylinders, manifolds, or ignition system. A
dual-ignition system, comprising a high-tension magneto for running
and a battery-and-coil auxiliary for starting; constant-level splash-

Fig. So. Holt Caterpillar Tractor for Plowing

lubricating system with an auxiliary force-feed oiler supplying oil
directly to the main bearings; a Schebler carburetor; and a centrifu-
gal pump for circulating the cooling water constitute the motor
essentials. Two flywheels are fitted, one of them being of unusually
liberal diameter and weight which permits the motor to develop its
rated output at the low speed of 600 r.p.m. A standard type of
fly-ball centrifugal governor mounted outside the crankcase on an
extension of the camshaft and acting directly on the throttle pre-
vents this speed from being exceeded. The cooling system consists
of a vertical tube radiator, a fan, and a large water tank, the mounting
of the motor and radiator being in accordance with standard truck
practice.

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Caterpillar Dricc. From the motor, the power is transmitted
through a multiple-disc clutch consisting of two large bronze discs
and three of iron, the former being carried on a steel ring driven by
casehardened lugs in the flywheel rim. The weight of the clutch
itself is carried by a self-aligning annular ball bearing mounted on
the end of the crankshaft. A heavy universal joint interpose!
between the clutch and the transmission takes care of any relative
movement. The relative locations of the motor, clutch, and trans-
mission can be noted in the illustrations of the frame, Fig. 86, the
motor being at the right, the clutch in the opening just back of
the transverse brace, while the lower half of the transmission case is

Fig. 86. Frame or Holt Caterpillar Traetor

bolted directly to the frame and has the bearings cast in gerally.
The forward, reverse, and bevel-reduction gears are located in this
case, the final, or main, driving gears, which run in oil, being placed
on each side of the housing in the broad troughs showTi. A shaft
extends outward from each one of these main driving gears and
carries on its outer end a spur pinion meshing with a large gear on
the same shaft as the sprocket, which is shown at the right of
Fig. 85. Each of these sprockets is controlled by a friction clutch
so that the two driving units are operated independently, and
no differential is required.

Engaging these sprockets are heavy block chains, the links, or
blocks, having blunt teeth to give traction in moist ground. As

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shown in Fig. 85, the weight of the tractor is carried by five grooved
steel wheels on each side, these wheels being mounted on a spring-
supported frame. On the upper side of this frame are three heavy
rollers to prevent the chain from the sagging due to its weight, while
at the forward end it is guided around a plain idler, or free-running
pulley. The driving effort is taken on the straight rod that bears on
the sprocket shaft at the rear end and is bolted directly to the frame
at its forward end. All bearings are lubricated by grease cups.
The chain links, or "track shoes", which are detachable, are made
heavy enough to withstand the most severe usage. They have
curved ends and overlap each other, so that there is no opening

Fig. 87. Holt Caterpillar Tractor Plowing

between them, even when the chain, or "track", is curved around
the sprocket. Owing to the great area in contact, there is practically
no friction between the shoes and the ground, and the track cannot
slip. The truck illustrated is for service on comparatively hard
surfaces, its width being increased in accordance with the nature
of the ground, and some of the tractors being fitted with tracks 30
inches in width. The upper face of the shoes forms a smooth steel
track on which the five weight-carrying wheels run. The rails of
the caterpillar track are made high and have openings at the side,
so that any dirt falling into the track is forced out through these
openings by the teeth of the track sprocket. As each track may be
driven separately through its friction clutch, the tractor can turn
in practically its own length by driving one of the tracks and letting

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the other remain idle, thus causing the machine to revolve almost
as if it were on a pivot. Fig. 87 illustrates one of these tractors
hauling a disc harrow and a leveling drag.

Avery Tractor. The Avery tractor, shown in Fig. 88, has 5 to 10
horsepower and has developed to meet the demand of the very small
farmer, gardener, orchard man, and even the contractor, for hauling
purposes, especially in connection with road building and road repair-
ing. This tractor will take the place of an ordinary four-horse team
and it can be easily adapted to any operation within its range of power.

Fig. 88. Avery 5 to 10 Horsepower Farm Tractor
Courtesy of Acery Company, Peoria, Illinois

The motor has heavy-duty bearings, large crankshaft, and heavy
drop-forged connecting rods; the cylinders are cast en bloc, with ample
water-cooling space. The wheel-base is 108 inches; two driving
wheels in the rear, 38 inches high and 5 inches wide, are provided
with internal gears, through which the engine power is delivered by
means of compensating gears mounted on the countershaft.

The rear frame is provided with a drawbar having a series of holes
crosswise of the machine to which implements or trailers may be
attached. The machine will burn gasoline or motor spirits, a tank
carrying 11 gallons being provided at the rear of the seat.

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GLOSSARY

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GLOSSARY

THE following glossary of automobile teijms is not intended in any sense
as a dictionary and only words used in the articles themselves have been
defined. The definitions have been made as simple as possible, but if
other terms unf amiliar to the reader are used, these should be looked up in order
to obtain the complete definition.

A. A. A.: Abbreviation for American Auto-
mobile Association.

Abrasive: Any hard substance used for
grinding or wearing away other substances.

Abeorber, Shock: See "Shock Absorber".

Accelerate: To increase the speed.

Acceleration: The rate of change of velocity
of a moving body. In automobiles, the ability
off the car to increase in speed. Pickup.

Accelerator: Device for rapid control of the
speed for quick opening and closing of the
throttle. Usually in the form of a pedal,
spring returned, the minimum throttle open-
ing being controlled by the setting of the
hand throttle.

Accessory: A subordinate machine that
accompanies or aids a more important
machine; as, a horn is an accessory of an
automobile.

Accumulator: A secondary battery or
storage battery. It usually consists of
chemically prepared lead plates combined
with an acid solution. Upon being charged
with an electric current from a primary
source, a chemical change takes place which
enables the plates in their turn to give a
current of electricity when used as a source
of power, the plates at the same time return-
ing to their original chemical state.

Acetone: A liquid obtained as a by-product
in the distillation of wood alcohol, and used
in connection with reservoirs for storing
acetylene for automobile lights, as it dis-
solves many times its own volume of acety-
lene gas.

Acetylated Alcohol: Alcohol which has been
denatured by the addition of acetylene,
which also increases its fuel value. See
"Alcohol, Denatured".

Acetylene: A gaseous hydrocarbide used as
an illuminant; is usually generated for that
purpose by the action of water on calcium
carbide.

Acetylene Generator. A closed vessel in
which acetylene gas may be produced by the
action of water on calcium carbide and which
supplies the gas under uniform pressure.

Acetylene Lamp: A lamp which burns
acetylene gas.

Acetyllte: Calcium carbide which has been
treated with glucose. It is used to obtain
a more uniform and slower production of
acetylene gas than can be obtained with the
untreated calcium carbide.

Acid: In connection with automobiles the
term usually means the liquid or electrolyte
used in the storage battery. See "Electro-
lyte".

Acid Cure. Method of rapid vulcanisation
of rubber without heat. Used in tire repairs.
The agent is sulphur chloride.

Acldlmeter. An instrument for determining
the purity of an acid.

Active Material: Composition in grids that
forms plates of a storage battery. It is this
material in which the chemical changes occur
in charging and discharging.

Adapter: Device by which one type of lamp
burner may be used instead of the one for
which the lamp was designed. Usually a
fitting by which a gas or oil lamp may be
converted into an electric lamp.

Adhesion: That property of surfaces in con-
tact by virtue of which one of them tends
to stick to the other. It is used as synony-
mous with friction. The adhesion of wheels
acts to prevent slipping.

Adjustment: The slackening or tightening
up of parts to compensate for wear, reduce
friction, or secure better contact.

Admission: In a steam engine, the letting
in of the steam to the cylinder; in gas engine,
the letting in of mixture of gas and air to the
cylinder.

Advanced Ignition: Usually called advanc-
ing the spark. Setting the spark of an inter-
nal-combustion motor so that it will ignite
the charge at an earlier part of the stroke.

Advance Sparking: A method by which the
time of occurrence of the ignition spark may
be regulated, by completing the electric
circuit at the earlier period.

Advancing the Spark: See "Advanced Ig-
nition".

Aerodynamics: The science of atmospheric
laws, i.e., the effects produced by air in
motion.

After-Burning: Continued burning of the
charge in an internal-combustion engine
after the explosion.

After-Firing: An explosion in the muffler or

exhaust passages.

A-h: Abbreviation for ampere hour.

Air Bottle: A portable container holding
eomprt*sscd air «>r carl>on dioxide for tire
inflation.

Air-Bound: See "Air Lock".

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GLOSSARY

Air Compressor: A machine for supplying
air under pressure for inflating tires, starting
the motor, etc.

Air Cooled: Cooled by air direct. Usually
referring to the cylinder of an engine, whose
heat caused by the combustion within it
is carried away by air convection and radia-
tion.

Air Cooling: A system of dispersing by air
convection the heat generated in the cylinder
of an internal-combustion motor.

Air Intake: An opening in a carbureter to
admit air.

Air Leak: Entrance of air into ihe mixture
between carbureter and cylinder.

Air Lock: Stoppage of circulation in the
water or gasoline system caused by a bubble
of air lodging in the top of a bend in the
pipe.

Air Pump: A pump operated by the engine
or by hand to supply air pressure to the oil
tank or gasoline tank; sometimes called
pressure pump.

Alr-Pump Governor: A device to regulate
the speed of the air pump so as to give a
uniform air pressure.

Air Resistance: The resistance encountered
by a surface in motion. This resistance in-
creases as the square of the speed, which
makes it necessary to employ four times as
much power in order to double a given speed.

Air Tube: See "Pneumatic Tire".

Airless Tire: Name of special make of non-
puncturable resilient tire.

A. L. A. M.: Abbreviation for Association
of Licensed Automobile Manufacturers, now
out of existence.

A. L. A. M. Horsepower Rating: The horse-
power rating of an automobile found by the
standard horsepower formula approved by
the Association of Licensed Automobile
Manufacturers. Since the dismemberment
of this organisation, the formula is usually
called the S.A.E. rating. This formula is
h.p. «=bore of cylinder (in inches) squared X
No. of cylinders-r-2 . 5, at a piston speed of
1000 r.p.m.

Alarm, Low-Water: See "Low- Water
Alarm".

Alcohol: A colorless, volatile, inflammable
liquid which may be used as fuel for internal-
combustion engines.

Alcohol, Denatured: Alcohol rendered unfit
for drinking purposes by the addition of
wood alcohol, acetylene, and other sub-
stances.

Alignment: The state of being exactly in
line. Applied to crankshafts a..d transmis-
sion shafts and to the parallel conditions of
the front and rear wheels on either side.

Alternating Current: Electric current
which alternates in direction periodically.

Ammeter: An instrument to measure the
values of current in an electric- circuit directly
in amperes. Also called ampere meter.

Amperage: The number of amperes, or cur-
rent strength, in an eleetrie circuit.

Ampere: The practical unit of rate of flow
•if electric current, measuring the current
intensity.

Ampere Hour: A term used to denote the
capacity of a storage battery or closed-circuit
primary battery. A battery that will deliver

three amperes for six hours is said to have an

eightcen-ampere-hour capacity.
Ampere Meter: See "Ammeter".
Angle-Iron Underframe: An underfrarne

constructed of steel bars whose cross section

is a right angle.
Anneal: To make a metal soft by heating and

cooling. To draw the temper of a metal.
Annular Gear: A toothed wheel upon which

the teeth are formed on the inner circum-
ference.
Annular Valve: A circular valve having a

hole in the center.

Annunciator: An installation of electric
signals or a speaking tube to allow the pas-
sengers in an enclosed car to communicate
with the driver.

Anti-Freezing Solution: A solution to be
used in the cooling system to prevent freezing
in cold weather; any harmless solution whose
freezing point is somewhat below that of
water may be used.

Anti-Friction Metal: Various alloys of tin
and lead used to line bearings, such as Babbitt
metal, white metal, etc.

An ti -Skid Device: Any device which may
be applied to the wheels of a motorcar tc
prevent their skidding, such as tire coverings
with metal rivets in them, chains, etc.

Apron: Extensions of the fenders to prevent
splashing by mud or road dirt.

Armature: In dynamo-electric machines,
the portion of a generator in which the
current is developed, or in a motor, the por-
tion in which the current produces rotation.
In most generators in automobile work, the
armature is the rotating portion. In mag-
netic or electromagnetic machines the arma-
ture is the movable portion which is attached
to the magnetic poles.

Armature Core: The iron portion of the
armature which carries the windings and
serves as part of the path for the magnetic
flux.

Armature Shaft: The shaft upon and with
which the armature rotates.

Armature Winding: Electrical conductors,
usually copper, in an armature, and in which
the current is generated, in case of a gen-
erator, or in which they produce rotation in
a motor.

Artillery Wheel : A wheel having heavy wood
spokes.

Aspirating Nozzle: An atomising nossle to
make the liquid passing through it pass from
it in the form of a spray.

Assembled Car: A car whose chief parts,
such as engine, gearset axles, body, etc., are
manufactured by different parts makers,
only the final process of putting them to-
gether being carried out in the car-making
plant .

Atmospheric Line: A line drawn on an in-
dicator diagram at a point corresponding
with the pressure of the atmosphere.

Atmospheric Valve: See "Suction Valve".

Atomizer: A device by which a liquid fuel,
such as gasoline, is reduced to small particles
or to a spray; usually incorporated in the
carbureter.

Auto: (1) Popular abbreviation for auto-
mobile. (2) A Greek prefix meaning self.

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GLOSSARY

Auto-Bus: An enclosed motor-driven public
conveyance, seating six or more people;
usually has a regular route of travel.

Autocar: A motorcar or automobile; a trade
name for a particular make of automobile.

Auto-Cycle: See "Motorcycle".

Autodrome: A track especially prepared for
automobile driving, particularly for races.

Autogenous Welding: See "Welding, Autog-
enous".

Auto-Igniter: A small magneto generator
or dynamo for igniting gasoline engines, the
armature of which is connected with the
flywheel by gears or by friction wheels, so
that electric current is supplied as long as
the engine revolves.

Autoist: One who uses an automobile.

Automatic Carbureter: A vaporizer or car-
bureter for gasoline engines whose action is
entirely automatic.

Automatic Cut-Out: See "Cut-Out, Auto-
matic".

Automatic Spark Advance: Automat io
variation of the instant of spark occurrence
in the cylinder. Mechanical advancing and
retarding of the spark to correspond with and
controlled by variations in crankshaft speed.

Auto-Meter: Trade name for special make
of combined speedometer and odometer.

Automobile: A motor-driven vehicle having
four or more wheels. Some three-wheeled
vehicles are proDerly automobiles, but are
usually called tricars.

Automobilist: The driver or user of an auto-
mobile.

Auto Truck: A motor-driven vehicle for
transporting heavy loads; a heavy com-
mercial car.

Auxiliary Air Valve: Valve controlling the
admission of air through the auxiliary air
intake of a carbureter.

Auxiliary Air Intake: Opening through
which additional air is admitted to the car-
bureter at high speeds.

Auxiliary Exhaust: Ports cut through cyl-
inder walls to permit exhaust gases to be
released from the cylinder when uncovered
by the piston. These are sometimes used
as an additional scavenging means for the
regular exhaust valves.

Auxiliary Fuel Tank: See "Fuel Tank,
Auxiliary".

Auxiliary Spark Gap: See "Spark Gap,
Outside".

Axle: The spindle with which a wheel revolves
or upon which it revolves.

Axle, Cambered: An axle whose ends are
slanted downwards to camber the wheels.

Axle, Channel: An axle which is U-shaped
in cross section.

Axle, Dead: Solid, fixed, stationary axle.

An axle upon which the wheels revolve but

which itself does not revolve.
Axle, Dropped: An axle in which the central

portion is on a lower level than the ends.
Axle, Floating: A full-floating axle. A live

axle in which the shafts support none of the

car weight, but serve only to turn the wheels.
Axle, I -Beam: An axle whose cross section

is in the shape of the letter I.
Axle, Lire: An axle in which are comprised

the driving shafts that carry the power of the
motor to the driving wheels.
Axle, Semi-Floating: A live axle in which
the driving shafts carry a part of the car
weight as well as transmitting the driving
torque.

Axle, Three-Quarters Floating: A live
axle in which the shafts carry a part of the
weight of the car, but less than that carried
by the semi-floating axle. It is inter-
mediated by a floating axle and the semi-
floating axle.

Axle, Trussed: An axle in which downward
bending h prevented by a truss.

Axle, Tubular: An axle formed of steel tub-
ing. Usually applied to the front axles, but
somttimrs used in referring to tubular shafts
of rear axles.

Axle Casing: That part of a live axle that
encloses the driving shafts and differential
and driving gears. Axle housing.

Axle Housing: See "Axle Casing".

Axle Shaft: The member transmitting the
driving torque from the differential to the
rear wheels.

Babbitt: A soft metal alloy used for lining
the bearings of shafts.

Back -Firing: An explosion of the mixture
in the intake manifold or carbureter caused
by the communication of the name of ex-
plosion in the cylinders. Usually due to too
weak a mixture. Popping.

Back Kick: The reversal of direction of the
starting, caused by back-firing.

Backlash : The play between a screw and nut
or between the teeth of a pair of gear wheels.

Back Pressure: Pressure of the exhaust
gases due to improper design or operation of
the exhaust system.

Baffle Plate: A plate used to prevent too
free movement of a liquid in the container.
In a gas engine cylinder, a plate covering the
lower end of the cylinder to prevent too
much oil being splashed into it. The plate
has a slot through which the connecting rod
may work.

Balance Gear: See "Differential Gear".

Balancing of Gasoline Engines: Insuring
the equilibrium of moving parts to reduce
the vibration and shocks. •'

Ball-and -Socket Joint: A joint in which a
ball is placed within a socket recessed to fit
it, permitting free motion in any direction
within limits.

Ball Bearing: A bearing in which the rotat-
ing shaft or axle is carried upon a number of
small steel balls which are free to turn in
annular paths, called race*.

Balladeur Train: A French name for a slid-
ing change-speed gear.

Barking: The sound made by the explosions
caused by after-firing.

Base Bearing: See "Main Bearing".

Base Explosion: See "Crankcase Explosion".

Battery: A combination of primary or
secondary cells, as dry cells or storage cells.

Battery, Dry: See "Dry Battery".

Battery, Storage: See "Accumulator".

Battery Acid; The electrolyte in ft storage
battery,

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GLOSSARY

Pfcrtery-Charglng Plug: Power terminals
to which the leads of a storage battery may
be connectec for charging the battery.

Battery Gage: (1) Voltmeter or ammeter
or voltammeter (or testing the specific
gravity of the electrolyte in a secondary
battery.

Battery Syringe: A syringe used to draw out
a part of the electrolyte or solution from a
storage battery cell to test its density and
specific gravity.

Baume: A scale indicating the specific
gravity or density of liquids and having
degrees as units. Gasoline of a specific
gravity of .735 has a gravity of 61 degrees
Baume.

Bearing: A support of a shaft upon which it
may rotate.

Bearing, Annular Ball: A ball bearing con-
sisting of two concentric rings, between
which are steel balls.

Bearing, Ball: A bearing in which the
rotating shaft and the stationary portion of
the bearings are separated from sliding con-
tact by steel balls. A steel collar fitted to
the shaft rolls upon the balls, which in turn
roll upon steel cellar attached to the station-
ary portion of the bearing.

Bearing, Cup and Cone: A ball bearing in
which the balls roll in a race, which is formed
between a cone-shaped fixed collar and a
cup-shaped shaft collar.

Bearing, Main: The bearing in which
rotates the crankshaft of an engine.

Bearing, Plain: A bearing in which the
rotating shaft is in sliding contact with the
bearing supporting it.

Bearing, Radial: A bearing designed to
resist loads from a direction at right angles
to the axis of the shaft.

Bearing. Roller: A bearing in which the

Journal rests upon, and is surrounded by,
tardened steel rollers which revolve in a
channel or race surrounding the shaft.

Bearing. Thrust: A bearing designed to
resist loads or pressures parallel with the
axis of the shaft.

Bearing Cap: That portion of a plain bear-
ing detachable from the stationary portion,
and which holds the bearing bushing and
shaft.

Bearing Surface: The projected area of a
bearing in a perpendicular plane to the
direction of pressure.

Beau de Rochas Cycle: The four-stroke
cycle used in most internal-combustion
engines. This cycle was proposed by M.
Beau de Rochas and put into practical form
by Dr. Otto. See "Four-Cycle".

Belt and Clutch Dressing: A composition
to be applied to belts and clutches to prevent
them from slipping.

Belt Drive: A method of transmitting power
from the engine to the countershaft or jack
shaft by means of belts.

Benzine: A petroleum product having a
specific gravity between that of kerosene and

Sasoline. Its specific gravity is between 60
egrees and 65 degrees Baumd.

Benzol: A product of the distillation of coal
tar. Coal tar benzine. Used as a rubber
solvent and in Europe as a motor fuel.

Berllne Body: A limousine automobile body
having mora than two seats in the back part.

Bevel -Gear: Gears the faees of whose teeth
are not parallel with the shaft, but are on a
beveled edge of the gear wheel.

Bevel-Gear Drive: Method of driving one
shaft from another at an angle to the first.
The chief method of transmitting the drive
from the propeller shaft to the rear axle
shafts.

B. H. P.: An abbreviation for brake horse-
power.

Bicycle: A two-wheeled vehicle propelled by
the pedaling of the rider.

Binding Posts: See "Terminals'*.

Bleeder: A by-pass in the sight-feed of a
mechanical oiling system by which the oil
delivered through that feed is allowed to
pass out instead of going to the bearings-
Blister: A defect in tires caused by the
separation of the tread from the fabric

Block Chain: A chain used in automobiles*
bicycles, etc.. of which each alternate link
is a steel block.

Blow-Back: The backward rushing of the
fuel gas through the inlet valve into the
carbureter.

Blower Cooled: A gas engine cooled by
positive circulation of air maintained by a
blower.

Blow-Off: A blow-out caused by the edge of
the bead of tire becoming free from the rim
and allowing the tube to protrude through
the space thus formed.

Blow-Out: The rupture of both the inner
tube and outer casing of a pneumatic tire.

Blow-Out Patch: See "Patch, Tire Repair".

Body: (1) The superstructure of an auto-
mobile; the part that resembles and repre-
sents the body of a horse-drawn vehicle.
(2) In oils, the degree of viscosity. The
tendency of drops of oils to hang together.

Body Hangers: Attachments to or exten-
sions of the frame for holding the body of the
vehicle. They should be properly called
frame hangers.

Boiler: A vessel in which water is evaporated
into steam for the generation of power.

Boiler, Fire-Tube: A tubular steam boiler
in which the end plates are connected by a
number of open ended thin tubes, the spaces
around which are filled with water, the hot
gases passing through the tubes.

Boiler, Flash : A steam boiler in which steam
is generated practically instantaneously.
There is practically no water or steam stored
in the boiler. A flash generator.

Boiler, Water-Tube: A steam boiler in
which the water is carried in metal tubes,
around which the hot gases circulate.

Boiler Alarm: See "Low- Water Alarm".

Boiler Covering: A non-conducting sub-
stance used as a covering for boilers to pre-
vent loss of heat by radiation.

Boiler-Feed Pump: An automatic and self-
regulating pump for supplying a boiler with
feed water.

Boiler-Feed Regulator: A device to make
the feed- water supply of the boiler auto-
matic.

Bonnet: (1) The hood or metallic cover
over the front end of an automobile. See
"Hood". (2) The cover over a pump-
valve box, or a slide-valve casing. (3) A
cover to enclose and guide the tail end of a

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GLOSSARY

srteam-engine-valve spindle or the cover of a
piston-valve casing. (4) The pan under-
neath the engine in an automobile.
Boot: A covering to protect joints from dirt
and water or to prevent the leakage of grease.
(2) Space provided for baggage at the rear
of a car.
Bore: The inside diameter of the cylinder.
Boas: An enlarged portion of a part to give

a point for attachment of another part.
Bottom: The meshing of gears without

clearance.
Bow Separator: A part to prevent chafing

of the bows of a top when folded.
Boyle's Law of Gaaea: A law defining the
volume and pressure of gases at constantly
maintained temperatures. It states that
the volume of a gas varies inversely as the
pressure so long as the temperature remains
the same; or, the pressure of a gas is propor-
tional to its density.
Brake: An apparatus for the absorption of
power by friction, and by clamping some por-
tion of the driving mechanism to retard or
stop the forward motion of the car.
Brake, Air-Cooled : A brake whose parts are
ridged to present a large surface for trans-
ferring to the air the frictional heat generated
in them.
Brake, Band: A brake which contracts
upon the outside of a drum attached to some
part of the driving mechanism.
Brake, Constricting Band : A form of brake
applied by tightening a band around a pulley
or drum.
Brake, Differential: A brake acting upon

the differential gear.
Brake, Double- Acting: A brake which will
hold when the drum is rotating in either
direction.
Brake, Drum, and Band: See "Brake,

Band".
Brake, Emergency: A brake intended to be
used in case the service brake does not act
to a sufficient extent.
Brake, Expanding-Band: A drum brake in
which the braking force is exerted by a band
forced outward against the inner rim of a
pulley.
Brake, External-Contracting: A brake
consisting of a drum affixed to a rotating

Eart, the outer surface of whieh is encircled
y a contracting band.

Brake, Foot: A brake designed to be oper-
ated by the driver's foot. A pedal brake.
Usually the service brake.

Brake, Front-Wheel: A brake designed to
operate on the front wheels of the car.

Brake, Gearaet: A brake designed to act on
the transmission shaft and attached to the
gearbox.

Brake, Hand: A brake designed to be oper-
ated by means of a hand lever. Usually the
emergency brake.

Brake, Hub: A brako consisting of a drum
secured to one of the wheels. This is the
usual type.

Brake, Internal: A brake in which an ex-
panding mechanism is contained within a
rotating drum, the expansion bringing pres-
sure to Dear on the drum.

Brake, Internal-Expanding: A brake con-
sisting of a drum, against the inside of which
may So expanded a Dand or a shoe.

Brake, Motor: A brake in an electric vehicle
which acts upon the armature shaft of the
motor.

Brake, Service: A brake designed to be used
in ordinary driving. It is usually operated
by the driver's foot.

Brake, Shoe: A brake in which a metal shoe
is clamped against a revolving wheel.

Brake, Transmission: A brake designed to
act upon the transmission shaft.

Brake, Water -Cooled: A brake through
which water may be circulated to carry off
the frictional heat.

Brake Equalizer: A mechanism applied to a
system of brakes operated in pairs to assure
that each brake shall be applied with equal
force.

Brake. Horsepower: The horsepower sup-
plied by an engine as shown by the applica-
tion of a brake or absorption dynamometer.

Brake Housing: A casing enclosing the
brake mechanism.

Brake Lever: The lever by which the brake
is applied to the wheel.

Brake Lining: The wearing surface of a
brake; usually arranged to be easily replaced
when worn.

Brake Pedal: Pedal by which the brake is
applied.

Brake Pull Rod: A rod transmitting the
tension from the lever or pedal to the mova-
ble portion of the brake proper.

Brake Ratchet: A device by which the brake
lever or brake pedal can be set in position and
retained there; usually consists of a notched
quadrant with which a movable tongue on
the lever head or pedal engages,

Brake Rod: The rod connecting the brake
lever with the brake.

Brake Teat: A test of a motor by means of a
dynamometer to determine its power output
at different speeds.

Braking Surface: The surface of contact
between the rotating and stationary parts of
a brake.

Braze: To join by brasing.

Brazing: The process of permanently joining
metalparts by intense heat.

Breaker Strip: A strip of canvas placed
between the tread and body of an outer tire
casing to increase the wearing qualities.

Breather: An opening in the crankcase of a
gas engine to permit pressure therein to
remain equal during the movement of the
pistons.

British Thermal Unit. The ordinary unit of
heat. It is that quantity of heat required to
raise the temperature of one pound of pure
water one degree Fahrenheit at the tempera-
ture of greatest density of water.

Brougham Body: A closed-in automobile
body having windows at the side doors, and
in front, but with no extension of the roof
over the front seat.

Brush Holder: In electrical machinery, an
arrangement to hold one end of a connection
flexible in contact with a moving part of the
circuit.

B. T. U.: Abbreviation for British Thermal

Unit.
Buckboard : A four-wheeled vehicle in which

the body and springs are replaced by an

elastic board or frame

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GLOSSARY

Buckling: Irregularities in the shape of the
plates of storage cells following a too rapid
discharge.

Bumper: (1) A contrivance at the front of
the car to minimise shock of collision; it con-
sists of plungers working in tubes and gain-
ing elasticity from springs. (2) A bar placed
across the end of a car, usually the front
end, to take the shock of collision and thus
prevent damage to the car itself. A rubber
or leather pad interposed between the axle
and frame of a car.

Burner, "Torch** Igniter: A movable auxil-
iary vaporiser for starting the fire in steam
automobile burners.

Bushing: A bearing lining. Usually made
of anti-friction metal and capable of adjust-
ment or renewal.

Bus-Pipe: A manifold pipe.

Butterfly Valve: A valve inserted in a pipe,
usually circular and of nearly the same
diameter as the pipe, designed to turn upon
a spindle through its diameter and thus shut
off or permit flow through the pipe. Usually
employed for throttle valves and carbureter
air valves.

Buzzer: (1) A name sometimes applied to
the vibrator or trembler of a jump-spark
ignition coil. (2) A device used in place
of a horn, and consisting of a diaphragm
which is made to vibrate rapidly by an
electromagnet.

By-Pass: A small valve to provide a second-
ary passage for fluids passing through a
system of piping.

C: Abbreviation for a centigrade degree of
temperature.

Calcium Carbide: A compound of calcium
and carbon used for the generation of acety-
lene by the application of water.

Calcium Chloride: * A salt which dissolved
in water is used as an anti-freezing solution.

Cam: A revolving disk, irregular in shape,
fixed on a revolving shaft so as to impart to
a rod or lover in contact with it an intermit-
tent or variable motion.

Cam, Exhaust: A cam designed to operate
the exhaust of an engine.

Cam, Ignition: A cam designed to operate
the ignition mechanism. In magnetos it
operates the make-and-break device.

Cam, Inlet: A cam designed to operate the
inlet valve of an engine.

Camber: (1) The greatest depth of curva-
ture of a surface. (2) The amount of
bend in an axle designed to incline the
wheels.

Camber of Spring: The maximum distance
between the upper and lower parts of a
spring under a given load.

Cambered Frame: A narrowing of the front
of a motor car to permit of easier turning.

Cam Gear: The gear driving the camshaft
of a gas engine. In a four-cycle engine this
is the same as the two-speed gear.

Camshaft: A shaft by which the valve cams
arc rotated ; also known as t he secondary shaft.

Camshaft, Overhead: The camshaft carried
along or above the cylinder heads, to operate
overhead valves.

Camshaft Gears: The gears or train of
gears by which the camshaft is driven from

the crankshaft. Half-time gears, timing

gears, distribution gears.
Canopy: An automobile top that can not be

folded up.
Capacity of a Condenser: The quality of

electricity or electrostatic charge. Of a

storage oattery, the amount of electricity

which may be obtained by the discharge of

a fully charged battery. Usually expressed

in ampere hours.
Cape Hood: An automobile top which is

capable of either being folded up or extended.
Car: A wheeled vehicle.
Carbide: See "Calcium Carbide".
Carbide Feed : A type of acetylene generator

in which the calcium carbide is fed into the

water.

Carbon Bridge: Formation of soot between
points of spark plug.

Carbon Deposit: A deposit upon the inte-
rior of the combustion chamber of a gasoline
engine composed of carbonaceous particles
from the lubricating oil, too rich fuel mix-
ture, or road dust.

Carbon Remover: A tool or solution for
removing carbon deposits from the cylinder,
piston, or spark plug of a gasoline engine.
Carbonization: The deposit of carbon,
Carbureter: An appliance for mixing an
inflammable vapor with air. It allows air
to be passed through or over a liquid fuel
and to carry off a portion of its vapor mixed
with the air, forming an explosive mixture.

Carbureter, Automatic: A carbureter so
designed that either the air supply alone or
both the air and gasoline supplies are regu-
lated automatically.

Carbureter, Constant-Level: A carbureter

the level of the gasoline in which is main-
tained automatically at a constant height.
A float-feed carbureter.

Carbureter, Exhaust -Jacketed : A carbu-
reter whose mixing chamber is heated by the
circulation of exhaust gas.

Carbureter, Multiple- Jet: A carbureter
having more that one spray nozzle or jet.

Carbureter, Water- Jacketed : A carbureter
whose mixing chamber is heated by the cir-
culation of water from the cooling system.

Carbureter Float: A buoyant part of the
carbureter designed to float in the gasoline
and connected to a valve controlling the
flow from the fuel tank, designed to main-
tain automatically a constant level of the
gasoline in the flow chamber.

Carbureter Float Chamber: A reservoir

containing the float and in which a con-
stant level of fuel is maintained.

Carbureter Jet: The opening through which
liquid fuel is ejected in a spray from the
standpipe of a carbureter nozile.

Carbureter Needle Valve: A valve control-
ling the flow of fuel from the flow chamber
to the standpipe.

Carbureter Nozzle: See "Carbureter Jet".

Carbureter Standpipe: A vertical pipe
carrying the nozzle.

Carburetlon: The process of mixing hydro-
carbon particles with the air. The action in
a carbureter.

Cardan Joint; A universal joint or Hooke's

coupling,

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GLOSSARY

Cardan Shaft: A shaft provided with a

Cardan joint at each end.
Casing: The shoe or outer covering of a

double-tube automobile tire.
Catalytic Ignition: See "Ignition.Catalytic".
Cell: One of the units of a voltaic battery.
Cell, Dry: See "Dry Cell".
Cell, Storage: See "Accumulator".
Cellular Radiator: A radiator in which the
openings between the tubes are in the form
of small cells. The same as a honeycomb
radiator.
Cellular Tire : A cushion tire which is divided

into compartments or cells.
Center of Gravity: That point in a body,
which, if the body were suspended freely in
equilibrium, would be the point of applica-
tion of the resultant forces of gravity acting
upon the body.
Center Control: The location of the gear-
shift and emergency brake levers of a car in
the center of a line parallel to the front of
the front seat.
Centigrade Scale: The thermometer scale
invented by Celsius. Used universally in
scientific work.
Century. In automobiling, a hundred-mile

run.
C. G.S. System: Abbreviation for centi-
meter-gram-second system of measurement;
the standard system in scientific work.
Chain, Drive: A heavy chain by which the
power from the motor may be transmitted
to the rear wheels of an automobile.
Chain, Roller: A sprocket chain, the cross

bars of whose links are rollers.
Chain, Silent: See "Silent Chain".
Chain, Tire: A small chain fastened about
the tire to increase traction and prevent
skidding.
Chain Wheel: A sprocket wheel for the
transmission chains of a motor-driven
vehicle.
Change-Speed Gear: See "Gear, Change-
Speed".
Change-Speed Lever: See "Lever, Change-
Speed".
Charge: The fuel mixture introduced into
the cylinder of a gas engine. The act of
storing up electric energy in an accumulator.
Charging: The passing of a current of elec-
tricity through a storage cell.
Charles* Law of Gases: See "Gases, Gay

Lussac's Law of".
Chassis. The mechanical features of a motor
car assembled, but without body, fenders, or
other superstructure not essential to the
operation of the car.
Chauffeur: In America this term means the
paid driver or operator of a motor car. The
literal translation from the French means
stoker or fireman of a boiler.
Check, Steering: Sec "Steering Check".
Check Valve: An automatic or non-return
valve used to control the admission of feed
water in the boiler, etc.
Choke: The missing of explosions or poor

explosions due to too rich mixture.
Circuit, Primary: Sec "Primary Circuit".
Circuit, Secondary: See "Secondary Cir-
cuit".

Circuit Breaker: A device installed in an
electric circuit and intended to open the
circuit automatically under predetermined
conditions of current flow.

Circulating Pump: A pump which keeps a
liquid flowing through a series of pipes which
provides a return circuit. In a motor car.
water and oil circulation is maintained by
circulating pump.

Circulation Pump: A mechanically oper-
ated pump by which the circulation of water
in the cooling system is maintained.

Circulating System: The method or series
of pipes through which a continuous flow of
water or oil is maintained and in which the
liquid is sent through the system over and
over.

Clash Gear: A sliding change-speed gear.

Clearance: (1) The distance between the
road surface and the lowest part of the
under-body of an automobile. (2) The
space between the piston of an engine when
at the extremity of its stroke, snathe head
of the cylinder.

Clearance, Valve: See "Valve Clearance".

Clearance Space: The space left between
the end of the cylinder and the piston plus
the volume of the ports between the valves
and the cylinder.

Clevis: The fork on the end of a rod.

Clevis Pin: The pin passing through the
ends of a clevis and through the rod to which
the clevis is joined.

Clincher Rim : A wheel rim having a turned-
in edge on each side, forming channels. Into
this the edge or flange of the tire fits, the air
pressure within locking the tire and rim
together.

Clincher Tire: A pneumatic tire design to
fit on a clincher rim.

Clutch: A device for engaging or discon-
necting two pieces of shafting so that they
revolve together or run free as desired.
Clutch Cone: A clutch whose engaging sur-
faces consist of the outer surface of the
frustrum of one cone and the inner surface
of the frustrum of another.
. Clutch, Contracting- Band: A clutch con-
sisting of a drum and band, the latter con-
tracting upon the former.
Clutch, Dry-Plate: A clutch whose friction
surfaces are metal plates, not lubricated.

Clutch, Expanding- Band: A clutch consist-
ing of a drum and band, the latter expanding
within the former.

Clutch, Jaw: A clutch whose members lock
end to end by projections or jaws in one
entering corresponding depressions in the
other.

Clutch,< Multiple-Disk: A clutch whose
friction surfaces are metal plates or disks,
alternate disks being attached to one mem-
ber and the rest to the other member of the
drive.

Clutch Brake: A device designed to stop
automatically the rotation of the driven
member of a clutch after disengagement
from the driving member.

Clutch Lining: The wearing surface of a
clutch. This may be easily removed and
replaced when worn.

Clutch Pedal: The pedal by which the
clutch may be disengaged, engagement being
obtained automatically by means of a spring.

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GLOSSARY

Clutch Sprint: A spring arranged to either
hold a clutch out of gear or throw it into
gear.

Coasting: The movement of the car without
constant applications of the motive power,
as in running downhill with the aid of grav-
ity or on the level, through the momentum
obtained by previous power applications.

Cock, Priming: A small cock, usually
operated by a lever, for admitting gasoline
to the carbureter to start its action.

Coll, Induction: See "Spark Coil".

Coll, Non- Vibrator: A coil so designed that
it will supply a sufficient spark for the igni-
tion with one make and break of the primary
circuit.

Coll, Primary: See "Primary Coil".

Coil, Secondary: See "Secondary Spark
Coil".

Coil, Spark: See "Spark Coil".

Coil, Vibrator: A spark coil with which is
incorporated an electromagnetic vibrator to
make and break the primary circuit.

Coil Vaporizer: An auxiliary vaporiser to
assist in starting a steam boiler. It is a coil
of tubing into which liquid gasoline is ad-
mitted and burned to start the generation of
gas in the main burner.

Cold Teat: The temperature in degrees
Tahrenheit at which a lubricant passes from
the fluid to the solid state.

Combustion Chamber: That part of an
explosive motor in which the gases are com-
pressed and then fired, usually by an electric
spark.

Combustion Space: See "Clearance" and
"Clearance Space".

Commercial Car: A motor-driven vehicle
for commercial use, such as transporting
passengers or freight.

Commutator: In the ignition system of an
explosive motor, the commutator is a device
to automatically complete the circuit of
each of a number of cylinders in succession.

Commutator of Dynamo or Motor: That
part of a dynamo which is designed to cause
the alternating current produced in the
armature to flow in one direction in the
external circuit j in a motor, to change the
direct current in the external circuit into
alternating current.

Compensating Carbureter: An automatic
attachment to a carbureter controlling
either air or fuel admission, or both, so that
the proportion of one to the other is always
maintained under any vibration of power
required.

Compensating Gear: See "Differential
Gear".

Compensating Joint: See "Universal
Joint".

Compound Engine: A multiple-expansion
steam engine in which the steam is expanded
in two stages, first in the high-pressure cyl-
inder and then in the low-pressure cylinder.

Compression: (1) That part of the cycle
of a gas engine in which the charge is com-
pressed before ignition; in a steam engine it
is the phase of the cycle in which the pres-
sure is increased, due to compression of the
exhaust steam behind the piston. (2) The
greatest pressure exerted on the gas in the
compression chamber.

Compression Chamber: The clearance vol-
ume above the piston in a gas engine; also
called "Compression Space".

Compression Cock: See "Compression-Re-
lief Cock".

Compression Line: The line on an indi-
cator diagram corresponding to the phase of
the cycle in which the gas is compressed.

Compression-Relief Cock: A small cock by
which the compression chamber of an inter-
nal-combustion motor may be opened to the
air and thus allow the compression in the
cylinder to be relieved to facilitate turning
by hand, or cranking.

Compression Space: See "Compression

Chamber".

Compression Teeter: A small pressure gage
by which the degree of compression of the
mixture in a gas-engine cylinder may be
tested.

Compressor, Air: See "Air Compressor".

Condenser: (1) In a steam motor, an
apparatus in which the exhaust steam is
converted back into water. (2) A device
for increasing the electric capacity of a
circuit. Used in an ignition circuit to
increase the strength of the spark.

Cone Bearing: A shaft bearing in which the
shaft is turned to a taper and the journal
turned to a conical or taper form.

Cone Clutch: A friction clutch in which
there are two cones, one fitting within the
other.

Connecting Rods: The part of an engine
connecting the piston to the crank, and by
means of which a reciprocating motion of
the piston is converted into the rotary
motion of the crank.

Constricting Band Brake: See "Brake,
Constricting Band".

Constricting Clutch: A friction clutch in
which a band is tightened around a drum to
engage it.

Contact Breaker: A device on some forma
of gasoline motors having an induction coil
of the single junu>spark type, to open and
close the electric circuit of the battery and
coil at the proper time for the passage of the
arc or spark at the points of the spark plug.

Contact Maker: See "Contact Breaker".

Continental Drive: Double-chain drive.

Control: The levers, pedals, etc., in general
with the speed and direction of a car is regu-
lated by the driver. In speaking of right,
left, or center control, the gearshift and
emergency brake levers only are meant.

Control, Spark: Method of controlling the
power of an engine by varying the point in
the stroke at which ignition takes place.

Control, Throttle: Method of governing
tho power of the engine by altering the area
of the passage leading to the admission
valve so that the amount of the fuel intro-
duced into the cylinder is varied.

Controller, Electric: Apparatus for secur-
ing various combinations of storage cells and
of motors so as to vary the speed of the car
at will.

Converter: A device for changing alternat-
ing current into direct current for charging
storage batteries, etc. Converters may be
any of three kinds: rotary, electrolytic, or
mercury-vapor. The mercury-vapor con-
verter is most widely used.

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GLOSSARY

Convertible Body: An automobile body
which may be used in two or more ways,
usually aa an open or closed carriage, or in
which several seats may be concealed, and
raised to increase the seating capacity.

Cooling Fan: Fan used in automobiles to
Increase the current of air circulating around
the cylinders, or through the radiator.

Cooling System: The parts of a gas engine
or motor car by which the heat is generated in
the cylinder by the combustion of the fuel
mixture. See "Water Cooling" and "Air
Cooling".

Cork Inserts: Pieces of cork inserted in
friction surfaces of clutches or brakes to
give softer action.

Cotter Pin: A split metal pin designed to
pass through holes in a bolt and nut to hold
the former in place.

Coulomb: The unit of measure of electrical
quantity. Sometimes called "Ampere Sec-
ond". It is equivalent to the product of
the current in amperes by the number of
seconds current has been flowing.

Counterbalance: Weights attached to a
moving part to balance that part.

Countershaft : An intermediate or secondary
shaft in the power-transmission system.

Coupe: An enclosed body seating one or two
passengers and the driver, all within.

Coupling, Flexible: See "Universal Joint".

Cowl: That portion of the body of the car
which forms a hood over the instrument
board or dash.

Cowl Tank: A fuel tank carried under the
cowl and immediately in front of the dash.

Crank: A lever designed to convert recipro-
cating motion into rotating motion or vice
versa; usually in the form of a lever formed
at an angle with the shaft, and connected
with piston by means of connecting rod.

Crank, Starting: A handle made to fit the
projecting end of the crankshaft of a gas
engine, so that the engine may be started
revolving by hand.

Crankcase: The casing surrounding the
crank end of the engine.

Crankcase Explosion: Explosion of un-
burned gases in the crankcase.

Crank Chamber: The enclosed space of
small engines in which the crank works.

Cranking: The act of rotating the motor by
means of a handle in order to start it. Turn-
ing the flywheel over a few times causes the
engine to take up its cycle, and after an
explosion it continues to operate.

Crankpin: The pin by which the connecting
rod is attached to the crank.

Crankshaft: The main shaft of an engine.

Crankshaft, Offset: A crankshaft whoso
center line is not in the same plane as the
axis of its cylinders.

Creeping of Pneumatic Tires: The tend-
ency of pneumatic tires to push forward
from the ground, and thus around the rim, in
the effort to relieve and distribute the
pressure.

Cross Member: A structural member of the
frame uniting the side members.

Crypto Gear: See "Planetary Gear".

Crystallization. The rearrangement of the
molecules of metal into a crytrtallinc form
under continued shocks. This is often the

cause of the breaking of the axles and jprings
of a motor car.

Cup, Priming: A small cup-shaped device
provided with a cock, by which a small
quantity of gasoline can be introduced into
the cylinder of a gasoline engine.

Current: The rate of flow of electricity; the
quantity of electricity which passes per
second through a conductor or circuit.

Current Breaker: See "Contact Breaker'*.
Current Indicator: A device to indicate

the direction of current flow in a circuit; a

polarity indicator.

Current Rectifier: A device for converting
alternating current into direct current. See
"Converter".

Cushion Tire: See "Tire, Cushion".

Cut-Off, Gas Engine: That point in the
cycle of an internal-combustion engine at
which the admission of the mixture is dis-
continued by the closing of the admission
valve.

Cut-Off, Steam Engine: That point in the
cyle of a steam engine, or that point on an
indicator diagram, at which the admission
of steam is discontinued by the closing of the
admission valve.

Cut-Out, Automatic: A device in a bat-
tery charging circuit designed to disconnect
the battery from the circuit when the cur-
rent is not of the proper voltage.

Cut-Out, Muffler: A device by which the
engine is ^ made to exhaust into the air
instead of into the muffler.

Cut-Out Pedal: Pedal by means of which
the engine is made to exhaust into the air
instead of into the muffler.

Cycle: A complete series of operations
beginning with the drawing in of the work-
ing gas, and ending after the discharge of
the spent gas.

Cycle, Beau de Roches: See "Beau de
, Rochas Cycle".

Cylinder: A part of a reciprocating engine
consisting of a cylindrical chamber in which
a gas is allowed to expand and move a
piston connected to a crank.

Cylinder Bore: See "Bore".

Cylinder Cock: A small cock used to allow
the condensed water to be drained away
from the cylinder of a steam engine, usually
called a drain cock.

Cylinder Head: That portion of a cylinder
which closes one end.

Cylinder Jacket: See "Jacket, Water".

Cylinder Oil: Lubricant particularly adapt-
ed to the lubrication of cylinder walls and
pistons of engines.

Dash : The upright partition of a car in front
of the front seat and just behind the bonnet.

Dash Adjustment: Connections by which
a motor auxiliary may be adjusted by a
handle on the dash. Usually applied to
carbureter adjustments.

Dash Coil: An induction coil for jump-
spark ignition, having an element for each
cylinder, with dash connections to the com-
mutator on the engine or camshaft.

Dash Gage: A steam, water, oil, or electric
gage placed upon the dash of the car.

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GLOSSARY

Day Tjrpe of Engine: The two-cycle inter-
nal-combustion engine with an air-tight
crankcase.

Dead Axle: See "Axle, Dead".

Dead Center: The position of the crank and
connecting rod in which they are in the same
straight line. There are two positions, and
in these positions no rotation of the crank-
shaft is caused by pressure on the piston.

Decarbonizer: See "Carbon Remover".

Deflate: Reduction of pressure of sir in a
pneumatic tire.

Deflector: In a two-cycle engine, the curved
plate on the piston head designed to cause
the incoming charge to force out the exhaust
gases and thus assist in scavenging.

Deflocculated Graphite: Graphite so finely
divided that it remains in suspension in a
liquid.

Demountable Rim: A rim upon which a
spare tire may be mounted and carried, and
so arranged that it may be easily and quickly
taken off or put on the wheel.

Denatured Alcohol: See "Alcohol, De-
natured".

Densimeter: See "Hydrometer".

Depolarizer: Material surrounding the nega-
tive element of a primary cell to absorb the
gas which would otherwise cause polarising.

Detachable Body: A body which may be
detached from and placed upon the chassis.

Detachable Rim: See "Demountable Rim".

Diagram Indicator: See "Indicator Card".

Diagram, Jeantaud: A diagrammatic rep-
resentation of the running gear of an auto-
mobile, showing it turning corners of various
radii for the purpose of determining the
front-axle and steering connections.

Diesel Gas Engine: Four-cycle internal-
combustion engine in which the explosion of
the charge is accomplished entirely by the
temperature produced by the high com-
pression of the mixture.

Differential, Bevel-Gear: A balance gear in

which the equalising action is obtained by

means of bevel gears.
Differential. Spur-Gear: A differential gear

in which the equalising action is obtained by

spur gears.

Differential Brake: See "Brake, Differen-
tial".

Differential Case: See "Differential Hous-
ing".

Differential Gear: A mechanism to permit
driving the wheels and yet allow them to
turn a corner without slipping. An arrange-
ment such that the driving wheels may turn
independently of each other on a divided
axle, both wheels being under the control
of the driving mechanism. Sometimes
called balance, compensating, or equalizing
gear.

Differential Housing: The case that en-
closes the differential gear.

Differential Lock: A device which prevents
the operation of the differential gear, so that
the wheels turn as if they were on a solid
shaft.

Dimmer: An arrangement for lowering the
intensity of, or reducing the glare from
headlights.

Direct Current: A current which does not
change its direction of flow, as the current

from a battery or a direct-current generator.
Distinguished from an alternating current,
which reverses its direction many times a
minute.

Direct Drive: Transmission of power from
engine to the final driving mec hanis m at
crankshaft speed.

Discharge: In a storage battery, the passage
of a current of electricity stored therein. In
the ignition circuit, the flow of high-tension
current at the spark gap.

Disk Clutch: A clutch in which the power
is transmitted by a number of thin plates
pressed face to face.

Distance Rod: See "Radius Rod".

Distribution Shaft: See "Camshaft".

Distributor: That part of the ignition svs-
tem which directs the high-tension current,
to the respective spark plugs in the proper
firing order.

Double Ignition: A method of ignition
which comprises two separate system*,
either of which may be used independently
of the other, or both together as desired.
Usually distinguished by two current
sources and two sets of plugs.

Drag: That action of a clutch or brake
which does not completely release.

Drag Link: That rod in a steering gear
which forms the connection between the
mechanism mounted on the frame and the
axle stub, and transmits the movements of
steering from steering post to wheels.

Drive Shaft: The shaft transmitting the
motion from the change gears to the driving
axle; the torsion rod.

Driving Axle: The axla of a motor car
through which the power is transmitted to
the wheels.

Driving Wheel: The wheel to which or by

which the motion is transmitted.
Dry Battery: A battery of one or more drv

cells.

Dry Cell: A primary voltaic cell in which a
moist material is used in place of the ordi-
nary fluid electrolyte.

Dual Ignition: An ignition system compris-
ing two sources of current and one set of
spark plugs.

Dust Cap: A metal cap to be screwed over
a tire valve to protect the latter from dust
and water.

Dynamo: The name frequently applied to a
dynamo-electric machine used as a gener-
ator. Strictly, the term dynamo should be
applied to both motor and generator.

Dynamometer: The form of equalising gear
attached to a source of power or a piece of
machinery to ascertain the power necessary
to operate the machinery at a given rate of
speed and under a given load.

Earth: See "Ground".

Economizer, Gas: An appliance to be
attached to a float-feed carbureter to im-
prove the mixture by automatically govern-
ing the amount of air in the float chamber.

Eccentric: A disk mounted off-center on a
shaft to convert rotary into reciprocating
motion.

Economy, Fuel: The fuel economy of a
motor is the relation between the heat units

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GLOSSARY

in the fuel used in the motor and the work
or energy given out by the motor.
Efficiency: The proportion of power ob-
tained from a mechanism as compared with
that put into it.
Efficiency of a Motor: The efficiency of a
gasoline motor is the relation between the
heat units consumed by the motor and the
work of energy in foot-pounds given out by
it. Electrical efficiency of a motor is the
relation between the electrical energy put
into the motor and the mechanical energy
given out by it.
Ejector: An apparatus by which a Jet of
steam propels a stream of water in almost
the same way as an injector, except that the
ejector delivers it into a vessel having but
little pressure in it.
Electric Generator: A dynamo-electric ma-
chine in which mechanical energy is trans-
formed into electrical energy; usually called
dynamo.
Electric Horn: An automobile horn elec-
trically operated.
Electric Motor: A dynamo-electric machine
in which electrical energy is transformed into
mechanical energy.
Electric Vehicle: An automobile propelled
by an electric motor, for which current is
supplied by a storage battery carried in the
vehicle.
Electrolyte: A compound which can be
decomposed by electric current. In refer-
ring to storage batteries, the term electro-
lyte means the solution of sulphuric acid in
water in which the positive and negative
plates are immersed.
Electromagnet: A temporary magnet which
obtains its magnetic properties by the action
of an electric current around it and which
is a magnet only as long as such current is
flowing.
Electromotive Force: A tendency to cause a
current of electricity to flow; usually syn-
onymous with potential, difference of poten-
tial, voltage, etc.
Element: The dissimilar substances in a
battery between which an electromotive
force is set up, as the plates of a storage
battery.
Emergency Brake: A brake to be applied
when a quick stop is necessary; usually
operated by a pedal or lever.
En Bloc: That method of casting the cylin-
ders of a gasoline engine in which all the
cylinders are made as a single casting.
Block casting; monoblock casting.
End Play: Motion of a shaft along its axis.
Engine, Alcohol: An internal-combustion
engine in which a mixture of alcohol and air
is used as fuel.
Engine, Gasoline: An internal-combustion
motor in which a mixture of gasoline and air
is used as fuel.
Engine, Kerosene: An internal-combustion
engine in which a mixture of kerosene and
air is used as fuel.
Engine, Steam: An engine in which the
energy in steam is used to do work by
moving the piston in a cylinder.
Engine Primer: A small pump to force fuel

into the carbureter.
Engine Starter: An apparatus by which a
gasoline engine may be started in its cycle of
operations without use of the starting crank.

It belongs usually to one of four classes: (1)
Mechanical or spring actuated, such as a
coil spring wound up by the running of the
engine or a strap around the flywheel; (2)
fluid pressure, Buch as compressed air or
exhaust gases induced into the cylinder to
drive the piston through one cycle; (3) the
electric system, in which a small motor is
used to turn the engine over; (4) combina-
tions of these.
Epicyclic Gear: See "Planetary Gear".
Equalizing Gear: See "Differential Gear".
Exhaust: The gases emitted from a cylinder
after they have expanded and given up their
energy to the piston; the emission of the
exhaust gases.
Exhaust, Auxiliary: See "Auxiliary Ex-
haust".
Exhaust Horn: An automobile horn in
which the sound is produced by the exhaust
gases.
Exhaust Lap: The extension of the inside
edges of a slide valve to give earlier closing
of the exhaust. Also called inside lap.
Exhaust Manifold : A largo pipe into which the
exhaust passages from all the cylinders open.
Exhaust Port: The opening through which
the exhaust gases are permitted to escape
from the cylinder.
Exhaust Steam: Steam which has given up
its energy in the cylinder and is allowed to
escape.
Exhaust Stroke: The stroke of an internal-
combustion motor during which the burned
gases are expelled from the cylinder.
Exhaust Valve: A valve in the cylinder of
an engine through which the exhaust gases
are expelled.
Expanding Clutch: A clutch in which a
split pulley is expanded to press on the inner
circuraferenco of a ring which surrounds it,
and thus transmits motion to the ring.
Expansion, Gas Engine: _ That part of the
cycle of a gas engine immediately after
ignition, in which the gas expands and drives
the piston forward.
Expansion, Steam Engine: That portion
of the stroke of the steam engine in which
the steam is cut off by the valves and con-
tinues to perform work on the piston, increas-
ing in volume and decreasing in pressure.
Explosive Motor : See ' ' Internal-Combustion
Motor".

Fan, Cooling: A mechanically operated fan
for producing a current of air for cooling the
radiator or cylinder of a gas engine.

Fan, Radiator: A mechanically operated
rotary fan used to induce the flow of air
through the radiator to facilitate the cooling
of the water.

Fan Belt: The belt which drives the cooling
fan.

Fan Pulley: A pulley permanently attached
to the fan and over which the fan belt runs
to drive it.

Fat Spark: A short, thick, ignition spark.

Feed Pump: A pump by which water is
delivered from the tank to the boiler of a
steam car.

Feed Regulator: A device to maintain a
uniform water level in a steam boiler by
controlling the speed of the feed pump.

371

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GLOSSARY

Feed-Water Heater: An apparatus for
heating the boiler-feed water, either by
means of a jet of steam or steam-heated
coils.

Fender: A mud guard or shield over the
wheels of a car.

Field, Magnetic: Space in the neighborhood
of the poles of a magnet in which the mag-
netism exerts influence. Field also refers to
the coils which produce the magnetism in an
electromagnet.

Fierce Clutch: A clutch which cannot be
engaged easily. A grabbing clutch.

Filler Board: Woodwork shaped to fill the
space between the lower edge of the wind-
shield and the dash.

Fin: Projections cast on the cylinders of a
gas engine to assist in cooling.

Final Drive: That part of a car by which the
driving effort is transmitted from the parts
of the transmission carried on the frame to
the transmission parts on the rear axle.
The propeller shaft in a shaft-drive car.

Fire Teat: A test of a lubricant to determine
the temperature at which it will burn.

Firing: (1) Ignition of the charge in a gas
engine. (2) The act of furnishing fuel
under the boiler of a steam engine.

First Speed : That combination of transmis-
sion gears which gives the lowest gear ration
forward. Blow speed; low speed.

Flash Boiler: A boiler arranged to generate
highly superheated steam almost instan-
taneously, by allowing water to come in
contact with very hot metal surfaces.

Flash Generator: See "Flash Boiler".

Flash Point: The temperature at which an
oil will give off a vapor that will ignite when
a flame comes in contact with it.

Flash Teat: A test to determine the flash
point of oils.

Flexibility: In an engine the ability to do
useful work through a range of speeds.

Flexible Coupling: See "Universal Joint".

Flexible Shaft: A pliant shaft which will
transmit considerable power when revolving.

Flexible Tubing: A tube for the conduction
of liquids or gases, which may be bent at a
small radius without leaking.

Float Carbureter: A carbureter for gasoline
engines in which a float of cork or hollow
metal controls the height of the liquid in the
atomising noztle. Sometimes culled float-
feed carbureter.

Float Valve: An automatic valve by which
the admission of a liquid into a tank is con-
trolled through a lever attached to a hollow
sphere which floats on the surface of the
liquid and opens or closes the valve accord-
ing as it is high or low.

Floating Axle: See "Axle, Floating".

Floating the Battery on the Line: Charg-
ing the battery while it is giving out current.

Flooding: Excessive escape of fuel in a
carbureter from the spraying nozzle.

Flushing Pin: In a float-feed carbureter, a
pin arranged to depress the float in priming.
Also called primer and tickler.

Flywheel: A wheel upon the shaft of an
engine which, by virtue of its moving mass,
stores up the energy of the gas transmitted
to the flywheel during the impulse stroke
and delivers it during the rest of the cycle,
thus producing a fairly constant torque.

Flywheel Marking: Marks on the face of a

flywheel to indicate the time of valve open-
ing and closing and thus assist in valve
setting.

Foaming: See "Priming'*.

Fore Carriage: A self-propelled vehicle in
which the motor is carried on the forward
trucks, and propelling and steering is done
with the forward trucks.

Fore-Door Body: An automobile body hav-
ing doors in the forward compartment.

Four-Cycle or Four-Stroke Cycle: The
cycle of operations in gas engines occupying
two complete revolutions or four strokes.

Four-Wheel Drive: Transmission of driving
effort to all four wheels.

Fourth Speed: That combination of trans-
mission gears which gives the fourth from
the lowest gear ratio forward. Usually the
highest speed.

Frame: The main structural part of a chas-
sis. It is carried upon the axles by the
springs and carries the different elements of
the car.

Frame Hangers: See "Body Hangers".
Free Wheel: A wheel so arranged that it

can rotate more rapidly than the mechsvniam

which drives it.

Friction: The resistance existing bet-ween

two bodies in contact which tends to prevent

their motion on each other.
Friction Clutch: A device for coupling said

disengaging two pieces of shafting while in

motion, by the friction of cones or plates on

one another.
Friction Disk: The thin plate used in a disk

or friction clutch. See * T Diak Clutch".
Friction Drive: A method of transmitting

power or motion by frictional contact.

Fuel: A combustible substance by whose

/ combustion power is produced. Gasoline

and kerosene are the chief automobile fuel*.

Fuel Economy. See "Economy, Fuel".

Fuel Feed, Gravity: See "Gravity Fuel
Feed".

Fuel Feed, Pressure: See "Lubrication,
Force-Feed. "

Fuel Feed, Vacuum. See "Vacuum Fuel
Feed".

Fuel-Feed Regulator: A device in the fuel
system of steam motor by which the rate of
flow of fuel to the burner is automatically
regulated.

Fuel Level: The height of the top of the fuel
in the float chamber of a carbureter.

Fuel-Level Indicator: An instrument either
permanently connected to the fuel tank or
which may be inserted thereon to indicate
the quantity of fuel in the tank.

Fuel Tank, Auxiliary: A tank designed to
hold a supply of fuel in addition to that
carried in the main shaft.

Fuse: A length of wire in an electric circuit
designed to melt and open the circuit when
excess current flows through it and thus pre-
vent damage to other portions of the circuit.

Fusible Plug: A hollow plug filled with an
alloy which melts at a point slightly above
the temperature of the steam in a boiler, as
when the water runs low, thus putting out
the firo and preventing the burning out of
the boiler.

372

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GLOSSARY

Gage: (1) Strictly speaking, a measure of, or
instr ument for determining dimensions or
capacity. Practically, the term refers to an
instrument for indicating the pressure or
level of liquids, etc. (2) The distance be-
tween the forward or rear wheels measured
at the points of contact of the tires on the
road. Tread; track.
Gage Cock: A small cock by which a pipe

leading to a gage may be opened or closed.
Gage Lamp: Lamp, usually electric, placed
above or near the gages to enable them to bo
read at night.
Gage, Oil: See "Oil Gage".
Gage, Tire: See "Tire-Pressure Gage".
Gap: In automobiles, the spark gap.
Garage: A building for storing and caring

for automobiles.
Garage, Portable: A garage which may be
moved from one place to another either as a
whole or in sections.
Gaa: Matter in a fluid form which is elastic
and has a tendency to expand indefinitely
with reduction in pressure.
Gaa Economizer: See "Economiser".
Gaa Engine: An internal-combustion motor
in which a mixture of gas and air is used as
fuel. The term is also applied to the gaso-
line engine.
Gaa Engine, Otto: A four-stroke cycle
engine developed by Otto and using the
hot-tube method of ignition.
Gaa Generator: An apparatus in which a

gas is generated for any use.
Gaa Lamp: See "Acetylene Lamp".
Gases, Boyle'* Law of: See "Boyle's Law

of Gases .
Gaaea, Gay Lussac*s Law of: Called
Charles* • Law and the Second Law of Gases.
Law denning the physical properties of
gases at constantly maintained pressure.
It states that at constant pressure the vol-
ume of gas varies with the temperature, the
increase Deing in proportion to the change of
temperature and volume of the gas.
Gasket: A thin sheet of packing material or

metal used in making joints, piping, etc.
Gasoline: A highly volatile fluid petroleum
distillate; a mixture of fluid hydrocarbons.
Gasoline-Electric Transmission: A sys-
tem of propulsion in which a gasoline engine
drives an electric generator, and the power
is transmitted electrically to motors which
drive the wheels.
Gasoline Engine: An internal-combustion
motor in which a mixture of gasoline and air
is used as a fuel.
Gasoline Primer: The valve on the car-
bureter of a gasoline engine by which the
action of the engine can be started.
Gasoline-Tank Gage : A fuel-lever indicator

for gasoline.
Gasoline Tester: A hydrometer graduated
to indicate the specific gravity of gasoline,
usually in degrees Baume.
Gate: A plate which guides the geexshift

lever in making speed changes.
Gather: Convergence of the forward por-
tions of the front wheels. Toeing in.
Gay Lussac's Law of Gases: See "Gases,
Gay Lussac's Law of".

Gear, Balance: See "Differential Gear'*.
Gear, Bevel: See "Bevel Gear".
Gear, Change-Speed: An arrangement of
gear wheels which transmits the power of
the motor to the differential gear at variable
speeds independently of the motor speed.
Gear, Differential: See "Differential".
Gear, Fiber: A gear cut from a vulcanised

fiber blank.
Gear, Helical: A gear whose teeth are not

parallel to the axis of the cylinders.
Gear, Internal: A gear whose teeth project
inward toward the center from the circum-
ference of gear wheel.
Gear, Planetary: See "Planetary Gears".
Gear, Progressive: See "Progressive Change-
Speed Gears".
Gear, Rawhide: A gear cut from a blank

made up of compressed rawhide.
Gear, Selective: See "Selective Change-
Speed Gears".
Gear, Timing: See "Timing Gears".
<Gear, Worm: A helical gear designed for
transmitting motion at angles, usually at
right angles and with a comparatively great
speed reduction.
Gearbox : The case covering the change-speed

gears.
Gear Shifting: Varying the speed ration
between motor and rear wheels by operating
the change-speed gears.
Gear-Shift Lever: A lever by which the

change-speed gears are shifted.
Geared -Up Speed: A speed obtained by an
arrangement of gears in tho gearset such that
the propeller shaft rotates more rapidly than
the crankshaft.
Gearset: See "Gear, Change-Speed".
Generator, Acetylene: See "Acetylene Gen-
erator".
Generator, Electric: See "Electric Gener-
ator".
Generator, Steam: A steam boiler.
Generator Tubing : Tubing by which acety-
lene is conducted from the generator to the
lamp.
Gimbal Joint : A form of universal joint.
Gong: A loud, clear sounding bell, usually
operated either electrically or by foot power.
Governor: A device for automatically regu-
lating the speed of an engine.
Governor, Dynamo: A method of auto-
matic control of the generator (usually an
ignition generator, in automobile work) by
which its speed is maintained approximately
constant.
Governor, Hydraulic: A governor applied
to engines cooled by a pump circulation of
water in such a way that the throttle opening
is controlled by the pressure of the water.
Governor, Spark: A method of automati-
cally controlling the speed of the engine by
varying the time of ignition. See "Gov-
ernor".
Grabbing Clutch: See "Fierce Clutch".
Gradometer: An instrument for indicating
the degree of the gradient or the per cent of
the grade. It consists of a level with a
graduated scale.
Graphite: One of the forms in which carbon
occurs in matter. Also known as black Uad

373

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GLOSSARY

and plumbago. Used as a lubricant in pow-
dered or flake form in the cylinders of
explosive engines.

Gravity-Feed Oiling System: See "Lubri-
cation, Gravity".

Gravity Fuel Feed: Supply of fuel to the
carbureter from the tank by force of gravity.

Grease and Oil Gun: A syringe by means
of which grease or oil may be introduced
into the bearings of the machinery.

Grease Cup: A device designed to feed
grease to a bearing by the compression of a
hand screw.

Grid: A lead plate formed in the shape of a
gridiron to sustain and act as a conductor of
electricity for the active material in a
storage battery.

Grinding Valves: See "Valve Grinding".
Gripping Clutch: See "Fierce Clutch".
Ground: An electric connection with the
earth, or to the framework of a machine.

Half-Motion Shaft : See "Half-Time Shaft".

I la If -Time Gear: See "Timing Gears".

Half -Time Shaft: The cam shaft of a four-
cycle gas engine. It revolves at one-half
the speed of the crankshaft.

Hammer Break : A make-and-break ignition
system in which the spark is produced when
the moving terminal strikes the stationary
terminal like a hammer.

Header: A pipe from which two or more
pipes branch. Manifold.

Heater, Automobile: A device for warming
the interior of an automobile, usually electric,
or by means of exhaust gases or jacket
water.

High Gear: That combination of change-
speed gears which gives the highest speed.

High -Tension Current: A current of high
voltage, as the current induced in the second-
ary circuit of a spark coil.

High-Tension Ignition: Ignition by means
of high-tension current.

High-Tension Magneto: A magneto which
delivers high-tension current.

Honeycomb Radiator: A radiator consist-
ing of many very thin tubes, giving it a
cellular appearance.

Hood: (1) That part of the automobile
body which covers the frame in front of the
dash. The engine is usually under the hood.
(2) The removable covering for the motor.

Hooke's Coupler: See "Universal Joint".

Horizontal Motor: A motor the center line
of whose cylinder lies in a horizontal plane.

Horn, Automobile: A whistle or horn for
giving warning of the approach of the
automobile.

Horsepower: The rate of work or energy
expended in a given time by a motor. One
horsepower is the rate or energy expended
in raising a weight of 550 pounds one foot
in one second, or raising 33,000 pounds one
foot in one minute.

Horsepower Brake: The power delivered at
the flywheel of an internal combustion
engine as ascertained by a brake test.

Horsepower, Rated: The calculated power
which may be expected to be delivered by a
motor* In America the term usually refers

to the horsepower as calculated by the
D.A.hi. formula.

Hot-Air Intake: The pipe or opening con-
veying heated air to the carbureter.

Hot-Head Ignition : The method of igniting
the charge in a gas-engine cylinder bv main-
taining the head of the combustion chamber
at a high temperature from the internal heat
of combustion, as in the Diesel engine.

Hot-Tube Ignition: An ignition device
formerly used for gas engines in which a
closed metal tube is heated red-hot by a
Bunsen flame. When the compressed gasea
in the cylinder are allowed to come in con-
tact with this, ignition takes place.

Housing: A metallic covering for mo vine
parts. ^

H *!VL **) Abbreviation for horaewnoer. (2)

Abbreviation for high pre*»ure.
Hub Cap: A metal cap placed over the outer

end of a wheel hub.
Hydrocarbons: Chemical combinations of

carbon and hydrogen in varied proportions.

usually distillates of petroleum, sush as

gasoline, kerosene, etc.
Hydrometer: An instrument by which the

specific gravity or density of liquids may be

ascertained.

Hydrometer Scale, Baume's: An arbitrary
measure of specific gravity.

I-Beam: Sometimes called I Section. A struc-
tural piece having a cross section resembling
the letter I. I-Beam front axle.

Igniter: An insulated contact plug without
sparking points, used in make-and-break
ignition with low-tension magneto.

Igniter, High-Speed: An igniter having a
short spark coil for high-speed engines.

Igniter, Jump-Spark: A system of ignition
m which is used a current of high pressure,
which will jump across a gap in the high-
pressure circuit, causing a spark at the gap.

Igniter, Lead of: Amount by which the igni-
tion is advanced. See "Advanced Ignition".

Igniter, Primary: The apparatus in a pri-
mary circuit for making and breaking the
circuit.

Igniter Spring: A spring to quickly break
the circuit of a primary igniter.

Ignition, Advancing: See "Advanced Ig-
nition".

Ignition, Battery: A system which gets its
supply of current from a storage batterv or
dry cells. This system usually consists of a
battery, a step-up coil, and a distributor for
sending the current to the different spark
plugs.

Ignition, Catalytic: Method of ignition for
explosive motors based on the property of
some metals, particularly spongy platinum,
of becoming incandescent when in contact
with coal gas or carbonised air.

Ignition, Double: See "Double Ignition".

Ignition, Dual: See "Dual Ignition".

Ignition, Fixed: Ignition in which the
spark occurs at a given point in the cycle
and cannot be changed from that point at
the will of the operator except by retiming
the ignition system. Fixed spark.

Ignition, Generator : Ignition current which
is furnished by a combination lighting
generator and magneto. The generator i*

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'8'

GLOSSARY

fitted with mn interrupter and distributor.
Sometimes refers to system in which a gener-
ator charges a battery and the latter fur-
nishes the ignition current in connection
with a coil and distributor.
Ignition, High-Tenelon: Sometimes called
jump-spark. Ignition which is effected by
means of a high-tension or high-voltage
current which is necessary to jump a gap in
the spark plug.
Ignition, Hot-Head: See "Hot-Head Igni-
tion".
Ignition, Jump-Spark: See "Ignition,

High-Tension' ' .
Ignition, Low-Tension: See "Ignition,

Make-and-Break' ' .
Ignition, Make-and-Break: A system in
which the spark is produced by the breaking
or interruption of a circuit, the break
occurring in the combustion space of the
cylinder. The current used is of low-volt-
age, hence the synonym, low-tension ignition.
Ignition, Magneto: Ignition produced bv
an electric generator, called a magneto, which
is operated by the gas engine for which it
furnishes current. Dynamo ignition. Gen-
erator ignition.
Ignition, Master Vibrator: A system which
uses as many non-vibrator coils as there
are cylinders, and one additional coil, called
the master vibrator, for interrupting the
primary circuit for all coils. The master
vibrator also is used with vibrator coils in
which the vibrators are short-circuited.
Ignition, Premature: Ignition occurring so
^ar before the top dead center mark that the
explosion occurs before the piston has reached
upper dead center.
Ignition, Primary: An ignition system in
which a low-tension current flows through a
primary coil, the circuit being mechanically
opened, allowing a high-tension spark to
jimp across the gap. See "Primary Cod .
Ignition, Retarding: Setting the spark of
an internal-combustion motor so that the
ignition will occur at a later part of the
stroke.
Ignition, Self: Explosion of the combusti-
ble charge by heat other than that produced
by the spark. Incandescent carbon will
cause this. Motor overheating because of
lack of water is another cause.
Ignition, Single: A system using but one

source of current.
Ignition, Synchronized: Ignition by means
of which the timing in each cylinder of a
multicylinder engine is the same. In syn-
chronised ignition the spark occurs at the
came point in the cycle in each cylinder.
This type of ignition is obtained with a
magneto and is lacking in a multi-coil sys-
tem using vibrator coils.
Ignition, Timing of: The adjustment of the
ignition system so that ignition will take
place at the desired part of the cycle.
Ignition, Two-Independent: See "Igni-
tion, Double".
Ignition, Two-Point: A system comprising
two ignition sources, or a double-distributor
magneto, and two seta of spark plugs, both
of which spark at the same time.
Ignition Distributor: See "Distributor."
Ignition Switch: A control or switch for
turning the ignition current on and off volun-
tarily.

I. H. P.: Abbreviation for indicated horae-

power.
Indicated Horsepower: (1) The horse-
power developed t>y the fuel on the pistons,
in contradistinction to brake horsepower.
See "Horsepower, Brake". (2) The horse-
power of an engine as ascertained from an
indicator diagram.
Indicator: An instrument by which the
working gas in an engine records its working
pressure.
Indicator Card: A figure drawn by means
of an indicator by the working gas in an
engine. Also called indicator diagram.
Induction Stroke: The downstroke of a
piston which causes a charge, of mixture to
be drawn into the cylinder.
Inflammation: The act or period of com-
bustion of the mixture in the cylinder.
Inflate: To increase the pressure within a

tire by forcing air into it.
Inflator, Mechanical Tire: A small power-
driven air-pump for inflating the tire; either
driven by gearing, chain, or belt from the
engine shaft, or by friction from the flywheel.
Inherent Regulation: Expression applied
to elec*ric generators which use no outside
means of regulating the output, the regula-
tion being affected by various windings of
the armature and fields.
Initial Air Inlet: See "Primary Air Inlet".
Initial Preasure: Pressure in a cylinder
after the charge has been drawn in but not
compressed.
Injector: A boiler-feeding device in which
the momentum of a steam jet, directed by a
series of conical nozzles, carries a stream of
water into the boiler, the steam condensing
within and heating the water which it forces
along.
Inlet, Valve: The valve which controls the
inlet port and so allows or prevents mixture
from passing to the cylinder.
Inlet Port: Passage or entrance in the cylin-
der wall through which the fuel mixture is
taken. Sometimes called intake port.
Inlet Manifold: Sometimes called intake
manifold or header. A branched pipe con-
nected to the mixing chamber at one end
and at the branch ends to the cylinders so as
to communicate with the inlet ports.
Inlet Manifold, Integral: A manifold or

header cast integral with the cylinder.
Inner-Tire Shoe: A piece of leather or
rubber placed within the tire to protect the
inner tube.
Inner Tube: A soft air-tight tube of nearly
pure rubber, which fits within a felloe upon
the casing.
Inside Lap: See "Exhaust Lap".
Intake Manifold: The large pipe which
supplies the smaller intake pipes from each
cylinder of a gas engine.
Intake Pipe: Sometimes made synonymous
with inlet manifold. Correctly, the pipe
from the carbureter to the inlet manifold.
Intake Stroke: See "Induction Stroke".
Intensifler: See "Outside Spark Gap".
Intermediate Gear: A gear in a change-
speed set between high and low. In a
three-speed set it would be second speed-
In a four, either second or third,

375

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GLOSSARY

Intermediate Shaft: See "Shaft, Inter-
mediate".

Internal-Combustion Motor: Any prime
mover in which the energy is obtaineJ by
the combustion of the fuel within the
cylinder.

Internal Gear: See "Gear, Internal".

Interrupter: 8ee "Vibrator".

Keyway: Slot in a rotating member used to

hold the key
Kick Switch: Ignition twitch mounted so

that the driver can operate it with the foot.

Kilowatt: An electrical unit equal to IPX)
watt*.

Knuckle Joint: See "Swivel Joint".

Jack: A mechanism by which a small force
exerted over a comparatively large distance
is enabled to raise a heavy body. Used for
raising the automobile axle to remove the
weight from the wheels.

Jacket, Water: A portion of the cylinder
easting through which water flows to cool
the cylinder.

Jacket Water: The cooling water circulating
in a water-cooling system.

Jackshaft: Shaft used in double-chain drive
vehicles. Shaft placed transversally in the
frame and driving from its ends chains which
turn the rear wheels mounted on a dead
axle.

Jeantaud Diagram: See "Diagram, Jean-
taud".

Joint Knuckle: See "Swivel Joint."

Joule's Law of Gaaea: See "Gases, Joule's
Law of".

Jump Spark: A spark produced by a sec-
ondary jump-spark coil.

Jump Spark, Circuit Maker: A mechani-
cally operated switch by which the circuit in
a jump-spark ignition system is opened and
closed.

Jump-Spark Coil: An electrical transformer
ana interrupter, consisting of a primary
winding of a few turns of coarse wire sur-
rounding an iron core, and a secondary
winding consisting of a great number of
turns of very fine wire. The condenser is
usually combined with this. Also known as
secondary spark coil.

Jump-Spark Igniter: See "Igniter, Jump-
8park'\

Jump-Spark Plug: See "Spark Plug".

Junction Box: A portion of an electric-
lighting system to which all wires are carried
for the making of proper connections.

Junk Ring: A packing ring used in sleeve-
valve motors. It has the same functions as
a piston ring. See "Piston Ring".

Kerosene: A petroleum product having a
specific gravity between 58° and 40° Baumo*.
It is used as a fuel in internal-combustion
engines and can often be used in gasojine
engines by starting the engine on gasoline,
then switching to kerosene.

Kerosene Burner: A burner especially
adapted to use kcroseno as a fuel.

Kerosene Engine: An engine using kero-
sene as fuel.

Key: A semicircular or oblong piece of
metal used to hold a member firmly on a
revolving shaft so as to prevent the member
from rotating.

Key, Baldwin : A key with an oblong section.

Key, Woodruff: A key with a semicircular

Labor: The jerkv operation of an engine.
The engine is said to labor when it cannot
pull its load without misfiring or jerking.

Lag, Combustion: The time between the
instant of the spark occurrence and the
explosion.

Lag, Ignition: The time between the instant
of spark occurrence and the time at which
the spark mechanism producing it begins
to act.

Lamp, Trouble: Sometimes called inspec-
tion lamp. A small electric bulb carried in
a suitable housing, and attached to a long
piece of lamp cord. Used for inspecting
parts of the car.

Lamp Bulb: The incandescent bulb used in
a lamp.

Lamp Bracket: A support for a lamp.

Lamp Lighter: An apparatus for lighting
gas lamps by electricity. The lamps are
usually so arranged that by pushing the
button the gas is turned on and the spark
made at the same time.

Landaulet: A type of car which may be
used as an open or closed car. The rear por-
tion of the body may be folded down like a
top.

Landaulet Body: An automobile body
resembling a limousine body, but having a
cover fitted to the back, which may be let
down, leaving the back open. The top
generally extends over the driver.

Lap: To make parte fit perfectly by operat-
ing them with an abrasive, such as ground
glass, between the rubbing surfaces. To
finish.

Lap of Steam Valves: In the slide valve of
a steam engine, the amount by which the
admission edges overlap the steam port when
the valve is central with the cylinder case.

Lay shaft: A countershaft or secondary shaft
of a gearset operated by the main or shifter
shaft.

Lead, or Lead Wire: Any wire carrying
electricity.

Lead: In a steam engine the amount by
which the steam port is opened when the
piston is at the start of its stroke.

Lead Battery: See "Accumulator".

Lead of Igniter: See "Igniter, Lead of".

Lead of Valve: In an engine the amount by
which the admission port is opened when the
piston is at the beginning of the stroke;
according as this is greater or less, the admis-
sion of working fluid is varied through
sever" 1 fractions of the stroke.

Lean Mixture: Fuel after leaving the car-
bureter, which contains too much air in pro-
portion to the gasoline. Sometimes called
thin mixture, rare mixture, or weak mixture.

Lever, Brake: See "Brake L^ver."

Lever, Change-Speed: Lever by which the
different combinations of change gears are
made so as to vary the speed of the driving

376

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GLOSSARY

wheels in relation to the speed of the engine;
also called gearshift lever.

Lever, Spark: Lever by which the speed and
power of the engine are controlled by adjust-
ing the time of ignition.

Lever, Steering: See "Steering Lever".

Lever, Throttle: A lever by which the speed
and power of the engine are controlled by
adjusting the amount of mixture admitted
to the cylinder.

Lever Lock: An arrangement for locking the
gearshift lever in free position so that with
the engine running the driving axle will not
be driven.

Lift: The distance through which a poppet
valve is moved in opening from fully-closed
to fully-open position.

Lifting Jack: See "Jack".

Lighting Outfit, Electric: An outfit for
electrically lighting an automobile. This
usually consists of a dynamo, storage bat-
tery, and lamps and switchboard, with the
necessary wiring and cut-outs.

Limousine Body: An enclosed automobile
body having the front and sides with side
doors. The top extends over the seat of the
driver.

Liner: One or more pieces of metal placed
between two parts so they may be adjusted
by varying the thickness of the liner. Some-
times called a shim. Also refers to a tool
used for lining up parts.

Liner, Laminated : A liner or shim made in
a number of parts, the thickness being
varied by removing or adding parts.

Lines of Force: See "Field, Magnetic".

Link Motion: In a steam engine, the name
for the arrangement of eccentric rods, links,
hangers, and rocking shafts by which the
relative motion and position of the slide
valves are changed at will, providing for
varying rates of expansion of the steam and
thus varying the speed for either forward or
backward motion.

Live Axle: See "Axle, Live".

Lock, Auto Safety: A device arranged so
that it is impossible to start the motor car
except by the proper combination or key.

Lock Nut: A nut placed on a bolt immedi-
ately behind the main nut to keep the main
nut from turning.

Lock Switch: A switch in the ignition cir-
cuit so arranged that it can not be thrown on
except by the use of a key.

Lock Valve: A valve capable of being secured
with lock and key.

Long-Stroke: A gas engine whose stroke is
considerably greater than its bore.

Lost Motion: Sometimes called play or
backlash. Looseness of space between two
moving parts.

Louver: A slit or opening in the side of a
hood or bonnet of a motor car. Used to
allow air from the draft to escape. A venti-
lator.

Low Gear: The lowest speed gear. First
speed in a change-speed set.

Low-Speed Adjustment: A carbureter ad-
justment which regulates the mixture when
the motor is operating slowly, with little
throttling opening.

Low-Speed Band: The brake or friction
band which controls the low speed of a plan-
etary change-speed set.

Low-Tension Current: A current of low
voltage or pressure, such as is generated by
dry cells, storage battery, or low-tension
magneto.

Low-Tension Ignition: See "Ignition,
Make-and-Break".

Low -Tension Magneto: A magneto which
initially generates a current of low voltage.

Low-Tension Winding: The winding of a
transformer or induction coil through which
the primary or low-tension currentfiows.

Low Test: Gasoline which has a high den-
sity, thus giving a low reading on the Baume*
scale. Low-grade gasoline.

Low-Water Alarm: An automatic arrange-
ment by which notice is given that the
water in the boiler is becoming too low for
safety.

Lubricant: An oil or grease used to dimin-
ish friction in the working parts of machin-
ery.

Lubrication: To supply to moving parts
and their bearings grease, oil, or other lubri-
cant for the purpose of lessening friction.

Lubrication, Circulating: A system in
which the same oil is used over and over.

Lubrication, Constant-Level: A system
in which the level in the crankcase is kept to
a predetermined level by means of a pump.

Lubrication, Force-Feed: Method of lubri-
cating the moving parts of an engine by
forcing the oil to the points of application by
means of a pump.

Lubrication, Gravity: Method of supplying
oil to moving parts of an engine by having a
reservoir at a certain height above the highest
point to be lubricated and allowing the oil
to flow to the points of application by
gravity.

Lubrication, Non-Circulating: A system
in which the same oil is used but once.

Lubrication, Pressure-Feed: See "Lubri-
cation, Force-Feed".

Lubrication, Sight-Feed: System of lubri-
cation in which the oil pipe to different
points of application is led through a glass
tube in plain sight ; usually at a point on the
dashboard.

Lubrication, Splash: Method of lubricat-
ing an engine by feeding oil to the crank-
case and allowing the lower edge of the
connecting rod to splash into it.

Lubricator: A device containing and supply-
ing oil or grease in regular amounts to the
working parts of the machine.

Lubricator, Force-Feed: A pump-like de-
vice which automatically forces oil to the
moving parts.

Magnet: A piece of iron or steel which has
the characteristic properties of being able to
attract other pieces of iron and steel.

Magnet, Horseshoe: A magnet shaped like
the letter U.

Magnet, Permanent: A magnet which
when once charged retains its magnetism.

Magnetic Field: See "Field, Magnetic".

Magnetic Spark Plug: A spark plug used
in a make-and-break system of ignition in
which contact is obtained by means of a
magnet.

Magneto: See "Ignition, Magneto".

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GLOSSARY

Magneto: See "Magneto-Electric Gener-
ator".

Magneto, Double-Distributor: A magneto
with two distributors feeding two sets of
spark plugs, two in each cylinder and both
sparking at once. See "Ignition, Two-
Point."

Magneto, High -Tension: A magneto has
two armature windings and requires no out-
side coil for the generation of high-tension
current.

Magneto, Induction: A type of magneto in

which the armature and fields are stationary

and a rotator or spool-shaped piece of metal

is used to break the lines of fore**.
Magneto, Low-Tension : See ' ' Low-Tension

Magneto".
Magneto, Rotating Armature: A magneto

in which the armature winding revolves.
Magneto Bracket: A shelf or portion of the

crankcase web used to support the magneto.
Magneto Coupling: A flexible joint which

connects the magneto with a revolving

motor shaft.

Magneto Distributor: See "Distributor".

Magneto-Electric Generator: A machine
in which there are no field magnet coUs, the
magnetic field of the machine being due to
the action of permanent steel magnets.
Usually contracted to magneto.

Main Bearing: A bearing used for support-
ing the crankshaft.

Manifold: A main pipe or chamber into
which or from which a number of smaller
pipes lead to other chambers. Sec "Intake
Manifold", "Exhaust Manifold", and "Inlet
Manifold".

Manometer: A device for indicating either
the velocity or the pressure of the water in
the coiling system of a gasoline motor.

Master Vibrator: A single vibrator which
interrupts the current to each of a set of
several spark coils in order.

Mean Effective Pressure: The average
pressure exerted upon a piston throughout
its stroke.

M. E. P.: Abbreviation for mean effective
pressure.

Mercury Arc Rectifier : A mercury vapor con-
verter. See "Mercury Vapor Converter"*.

Mercury Vapor Converter: An apparatus
for converting alternating current into direct
current by means of a bubble of mercury in
a vacuum. The vapor of mercury possesses
the property of allowing the flow* of current
in one direction only. Its principal use is
for charging storage batteries.

Mesh: Two gears whose teeth are so posi-
tioned that one gear will drive the other are
said to be in mesh.

Misfire: Failure of the mixture to ignite in
the cylinder; usually due to poor ignition or
poor mixtures.

Miss: The failure of a gas engine to explode
in one or more cylinders. Sometimes called
misfiring.

Mixing Chamber: A pipe or chamber
placed between the carbureter and inlet
manifold. Sometimes integral with the car-
bureter or manifold.

Mixing Tube: A tubular carbureter for a
gas or gasoline engine.

Mixing Valve: A device through which air
and gas are admitted to form an explosive

mixture. The carbureter of a gasoS-w
engine combines the mixing valve ssi
vaporiser.

Mixture: The fuel of a gas engine, consist^
of sprayed gasoline mixed with air.

Mono bloc: Cast en bloc or in one pier*
Refers usually to cylinders, which are csrf
two or more at once.

Motocycle: A trade name for a special wwl*
of motorcycle.

Motor, Electric: See "Electric Motor".

Motor, Gasoline: See "Gasoline Motor".

Motor, High-Speed: A gas engine wb.w
rotative speed is very high and whose p*»«- -
output goes up with the speed to an unusui
degree.

Motor, Horizontal: A gas engine whose c\ -
inder axis lies in a horizontal plane.

Motor, I-head: A gas engine which ha*

cylinders, a section of which resembles th«-

letter I. This type has the vr.lves in tbt
head.

Motor, L-Head: A gas engine in which a
section of cylinders resembles the letter L.
The valves in this type are all on one &ide.

Motor, Long-Stroke: See "Long-Strokt
Motor".

Motor, Non-Poppet: A gas engine whose
valves are not of the poppet type. In ihi*
class is the Knight sleeve valve, the rotary
valve, and the piston valve.

Motor, Overhead Valve: A motor with cyl-
inders whose valves are in the head.

Motor, Piston Valve: A gas engine using
valves which are in the form of pistons.

Motor, Poppet: A gas engine using poppet-
type valves. See "Poppet Valve".

Motor, Revolving Cylinder: A motor whose
cylinders revolve as a unit.

Motor, Rotary Valve: One in which the
valves consist of slots cut out along cvlin-
drical rods which rotate in the cylinder
casting.

Motor, Sliding Sleeve: The Knight type
motor in which thin sleeves slide up and
down in the cylinder, the sleeves having
ports which register with the inlet and
exhaust manifolds.

Motor, T-Head: A gas engine with the
valves on opposite sides of the cylinders, a
section of which resembles the letter T.

Motor, V-Type: A motor whose cylinders
are set on the crankcase so as to form an
angle of 45 to 90 degrees between them.

Motor, Vertical: A motor with the cylinder
axis in a vertical plane.

Motorcycle: A bicycle propelled by a gaso-
line engine.

Mud Guard: Metal or leather strips placed
over the wheels to catch the flying mud and
to prevent the clothing from coming in con-
tact with the wheels when entering and
leaving the car.

Muffler Cut-Out: See "Cut-Out, Muffler".

Muffler Cut-Out Pedal: See "Cut-Out
Pedal".

Muffler Exhaust: A vessel containing par-
titions, usually perforated with small holes
and designed to reduce the noise occasioned
by the exhaust gases of an engine, by forcing
the gases to expand gradually,

378

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GLOSSARY

Muffler Explosion: Explosion of unburned
gases in exhaust passages of the muffler,
usually due to poor ignition or poor mixture.

Multiple Circuit: A compound circuit in
which a number of separate sources or
electrically operated devices, or both, have
all their positive poles connected to a single
positive conductor and all their negative
poles to a single negative conductor.

N.A.A.M.: Abbreviation for National Asso-
ciation of Automobile Manufacturers.

Naphtha: A product of the distillation of
petroleum use.d to some extent for marine
engines.

Needle Valve: A valve in a carbureter used
for regulating the amount of gasoline to flow
in with the mixture.

Negative Plate: Plate of a storage battery to
which current returns from the outside
circuit.

Negative Pole: That pole of an electric
source through which the current is assumed
to enter or now back into the source after
having passed through the circuit external
to the source.

Neutral Position: The position of the
change-speed lever which so places the gears
that the motor may run idle, the car remain-
ing still.

Non-Defla table Tire: See "Tire, Non-
Puncturable".

Non -Freezing Solution: A solution placed
into the radiator of a motor car to prevent
the water therein from freeiing. Alcohol
and glycerine arc the usual anti-freezing
agents. See "Anti-Free«ing Solution".

Non-Puncturable Tire: See "Tire, Non-
Puncturable".

Non-Skid Device: See "Anti-Skid Device".

Odometer: (1) The mileage-recording mech-
anism of a speedometer. (2) An instrument
to be attached to an automobile wheel to
automatically indicate the distance traveled.

Odometer, Hub: A speed-recording device
which is placed on the nub cap of a wheel.

Offset: Off center, as a crankshaft in which
a line vertically through the crankpins does
not coincide with a line vertically through
the center of the cylinder.

Ohm: (1) Unit of electrical resistance. (2)
Amount of electrical resistance. Such resist-
ance as would limit the flow of electricity
under an electromotive force of one volt to
a current of one ampere.

Ohm's Law: The law which gives the rela-
tion between voltage, resistance, and current
flow in any circuit. Expressed algebraically,

C— -= where C is the current flowing in am-

K
peres, J the voltage and R the ohmic resist-
ance.

Oil Burner: A burner equipped with an
atomizer for breaking up liquid fuel into a
spray.

Oil Engine: An internal-combustion motor
using Kerosene or other oil as fuel.

Oil Gage: (I) A gage to indicate the flow
of oil in the lubricating system. (2) Used
to show the level of oil in a compartment in
the base of a gas engine.

Oil Gun: A cylinder with a long point and a
spring plunger for squirting oil or grease
into inaccessible parts of a machine.

Oil Pump: A small force pump providing a
constant positive supply of oil under pres-
sure; usually considered to be more reliable
than a lubricator.

Oiler: An automobile device for oiling
machinery.

Opposed Motor: A gasoline engine whose
cylinders are arranged in pairs on opposite
sides of the crankshaft, both connecting
rods of each pair being connected to the
same crank, so that the shock of the explo-
sion in one will be balanced by the cushion-
ing effect of the compression in the other.
In general these motors are two-cylinder,
horizontal.

Otto Cycle: See "Four-Stroke Cycle".

Outside Spark Gap: See "Spark Gap, Out-
side".

Overcharged: The state of the storage bat-
tery when it has been charged at too high a
rate or for too great a length of time.

Overhead Camshaft: A camshaft which is
placed above the cylinder of a gas engine.

Overhead Valves: See "Motor, Overhead
Valve".

Overheating: The act of allowing the motor
to reach an excessively high temperature
due to the heat of combustion being not
carried away rapidly enough by the cooling
devices, or to insufficient lubrication. Over-
heating of a bearing is due to insufficient
lubrication.

Packing: The material introduced between
the parts of couplings, joints, or valves, to

f>revent the leakage of gas or liquids to or
rom them.

Panel, Charging: A small switchboard for
charging a storage battery.

Parallel Circuit: See "Multiple Circuit".

Patch, Tire-Repair: Rubber strips for mak-
ing repairs in punctured or ruptured tires.

Petcock: A control cock which when open
allows gas or liquid to escape from the cham-
ber to which it is attached:.

Petrol: Word used in 'England for gasoline.

Picric Acid: Acid which may be added to
gasoline to increase the motor efficiency.
Gasoline will absorb about five per cent of
its weight of picric acid.

Pin, Taper: A conically shaped pin.

Pinch: A cut in an inner tube caused by the
tube being caught or pinched between the
outer casing and the rim.

Pinion: (1) The smaller of any pair of
gears. (2) A small gear made to run with
a larger gear.

Piston: The hollow, cylindrical portion
attached to the connecting rod of a motor.
The reciprocating part which takes the
strain caused by the explosion.

Piston Air Valve: A secondary air valve in
the piston of earlier types of gas engines to
compensate the imperfect operation of sur-
face carbureters used with those engines
and to secure the injection of a sufficient
quantity of air to insure the combustion of
the charge.

Piston Head: The top of the pistoi).

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GLOSSARY

PUton Pin: A pin which holds the connect-
ing rod to the piston.

Piston Ring: (1) A metal ring inserted in a
groove cut into a piston assisting in making
the latter tight in the cylinder. There are
usually three rings on each piston. (2)
Rings about the circumference of a piston,
whose diameter is slightly greater than that
of the piston. These are to insure closer fit
and prevent wearing of the piston, as the
wear is taken up by the rings which may
be easily removed.

PUton Rod: Usually called connecting rod*
The rod which connects the piston with
the crankshaft.

PUton Skirt: The portion of a piston below
the piston pin.

PUton Speed : The rate at which the piston
travels in its cylinder.

PUton Stroke: The complete distance a
piston travels in its cylinder.

Pitted: Condition of a working surface which
has become covered with carbon particles
which have been imbedded in the metal.

Planetary Gear: An arrangement of spur
and annular gears in which the smaller gears
revolve around the main shaft as planets
revolve around the sun.

Planetary Transmission: A transmission
system in which the speed changes are ob-
tained by a. set of planetary gears.

Plate: Part of a storage battery which holds
active material. 8ee "Negative Plate".

Pneumatic Tire: A tire fitted to the wheels
of automobiles, consisting usually of two
tubes, the outer of India rubber, canvas, and
other resilient wear-resisting material, and
the inner composed of nearly pure rubber
which is inflated with compressed air to
maintain the outer tube jn its proper form
under load.

Polarizing: Formation of gas at the negative
element of a cell so as to prevent the action
of the battery. This formation of gas is
caused by the violent reaction taking place
in a circuit of low resistance.

Pole Piece: A piece of iron attached to the
pole of a magneto used in an electric gener-
ator.

Poppet Valve: A disk or drop valve usually
seating itself through gravitation or by
means of springs, and frequently opening by
suction or cams.

Port: An opening for the passage of the
working fluid in an engine.

Portable Garage: See "Garage, Portable".

Positive Connection: A connection by
which positive motion is transmitted by
means of a crank, bolt, or key, or other
method by which shipping is eliminated.

Positive Motion: Motion transmitted by
cranks or other methods in which slipping
is eliminated.

Positive Plate: Plate in a storage battcrv,
from which the current flows to the outside
circuit.

Positive Pole: The source from which elec-
tricity is assumed to flow; the opposite of
negative pole. In a magnet the positive pole
is the end of the magnet from which the
magnetic flux is assumed to emanate.

Pounding in Engine: Pounding noise at
each revolution, usually caused by either

carbon deposit, loose or tight piston, loose
bearing or other part, or pre-ignition.

Power Stroke: The piston stroke in a gas
engine in which the exploded gases are
expanding, thus pushing the piston down-
ward.

Power Tire Pump: A pump which ie oper-
ated by a gas engine and is used to inflate
the tires of a motor car.

Power Unit: The engine with fuel, cooling,
lubrication, and ignition systems, without
the transmission or running gears. Some-
times the gearset and driving shaft are
included by the term.

Pre-Ignitlon: See "Premature Ignition".

Premature Ignition: Ignition of fuel before
the proper point in the cycle.

Pressure-Feed: See "Lubrication, Force-
Feed".

Pressure Gage: A gage for indicating: the
pressure of a fluid confined in a chamber,
such as steam in a boiler, etc.

Pressure Lubricator: A lubricating device
in which the oil is forced to the bearings by
means of a pump or other device for main-
taining pressure.

Pressure Regulator: A device for main-
taining the pressure of the steam in the
principal pipe at a constant point irrespective
of the fluctuations of pressure in the boiler.

Primary Air Inlet: The main or fixed air
intake of a carbureter.

Primary Circuit: The circuit which carries
low-tension current.

Primary Coil: A self-induction coil consist-
ing of several turns of wire about an iron
core.

Primary Spark Coil: An induction coil
which has only a single winding composed
of a few layers of insulated copper wire
wound on a bundle of soft iron wires, known
as the core, also as a wipe, or touch, spark coil.

Primer: A pin in a float-feed valve so
arranged that it may depress the float in
priming a gasoline engine. Also called
tickler and flushing pin.

Priming: (1) The carrying of water over
with the steam from the boiler to the
engine, due to dirty water, irregular evapo-
ration, or forced steaming. (2) Injecting; a
small amount of gasoline into the cylinder
of a gasoline engine to assist in starting.

Priming Cock: A control cock screwed into
the cylinder and which when open com-
municates with the combustion chamber
allowing gasoline to be poured into the
cylinder.

Progressive Change-Speed Gears: Change-
speed gears so arranged that higher speeds
are obtained by passing through all the
intermediate steps and vice versa.

Prony Brake: A dynamometer to indicate
the horsepower of an engine. ^ A band
encircles the flywheel of the engine and is
secured to a lever, at the other end of which
is a scale to measure the pull.

Propeller Shaft: The shaft which turns the
rear axle of a motor car. The drive shaft.

Pump, Centrifugal: A pump with a hollow
hub and curved blades which by centrifugal
force throw water or oil into the system
requiring it.

Pump, Circulation: See "Circulation
Pump".

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GLOSSARY

Pomp, Fuel-Peed: A mechanically oper-
ated pump for insuring positive feed of fuel
to the burner of a steam engine or carbureter
of a gas engine.

Pump, Oil: See "Oil Pump".

Pump, Plunger: Sometimes called piston
pump. One containing a piston which
forces a liquid to a system.

Pump, Power Tire: See "Tire Pump".

Pump, Steam Boiler-Feed: See "Boiler-
Feed Pump".

Pump, Water Circulating: See "Circula-
tion Pump".

Pump Gear: A pump composed of two
gears in mesh placed in a housing. When
the gears revolve they carry oil or water, as
the case may be, on their teeth, which deliver
it to an outlet.

Puncture: The perforation of an inflated
rubber automobile tire by some sharp sub-
stance on the roadbed.

Puncture-Closing Compound: A viscous
compound placed within the inner tire tube
to close the hole caused by a puncture.

Push Rod: A rod which operates the valves
of a poppet-valve motor. A rod which
imparts a pushing motion.

Race: (1) The parts upon which the balls
of a ball bearing roll. (2) When referring
to a gas engine, to operate at high speed
without a load.

Racing Body: A low, light automobile body,
having two seats with backs as low as possi-
ble; designed for large fuel capacity and
very high speed.

Radiator: A device consisting of a large
number of small tubes, through which the
heated water from the jacket of the engine
passes to be cooled, the heat being carried
away from the metal of the radiator by air.

Radiator, Cellular: See "Honeycomb
Radiator".

Radiator, Tubular: A radiator consisting
of many tubes, through which water passes
to be cooled.

Radiator Protector: See "Bumper".

Radius Rod : A bar in the frame of an auto-
mobile to assist in maintaining the proper
distance between centers. Also called
distance rod.

Rawhide Gear: Tooth gears, built up of
compressed rawhide, used for high-speed
drive. Sometimes a metal gear is merely
faced with rawhide for the purpose of reduc-
ing noise.

Reach Rod: See "Radius Rod".

Reciprocating Parts: The parts such as
pistons and connecting rods which have a
reciprocating motion.

Rectifier, Alternating-Current: See "Cur-
rent Rectifier".

Relief Cock : See "Compression-Relief Cock".

Removable Rim : See "Demountable Rim".

Resiliency: That property of a materia
by virtue of which it springs back or recoils
on removal of pressure, as a spring.

Resistance, Electrical: (1) A part of an
electric circuit for the purpose of opposing
the flow of the current in the circuit. (2)
The electrical resistance of a conductor is

that quality of a conductor by virtue of
which the conductor opposes the passage of
electricity through its mass. Its unit is
the ohm.

Retard: With reference to the ignition sys-
tem, causing the spark to occur while the
piston is retarding or moving downward on
the working stroke.

Retarding Ignition: See "Ignition, Retard-
ing".

Retarding the Spark: See "Ignition, Re-
tarding .

Retread: To replace the tread of a pneu-
matic tire with a new one.

Reverse Cam: On a gasoline engine a cam
so arranged that by reversing its motion or
shifting it along its shaft it will operate the
valves and cause the engine to reverse.

Reverse Gear: In a steam engine, a device
by which the valves may be set to effect
motion of the car in either direction. In a
gasoline > automobile, the reversing gear is
usually incorporated with the change-speed
gears.

Reverse Lever: A lever by which the direc-
tion of movement of the driving wheels may
be reversed without reversing the engine.
This is usually combined with the change-
speed levers.

Rheostat: A device for regulating the flow
of current in a closed electrical circuit by
introducing a series of graduated resistances
into the circuit.

Rim: The portion of a wheel to which a solid
or pneumatic tire is fitted. A circular,
channel-shaped portion attached to the
wheel felloe.

Rim, Demountable: A rim which may be
removed from the wheel easily in order that
another with an inflated tire may take its
place.

Rim, Quick-Detachable: A rim made of
two or more parts so that the tire may be
detached and attached quickly.

Rim, Removable: See "Demountable Rim".

Road Map: A map of a section or locality
showing the best roads for motor-car travel,
and usually the best stopping places and
repair stations.

Roadster: A small motor car designed to be
fairly speedy; usually has carrying capacity
for an extra large quantity of fuel and sup-
plies; generally seats two persons, with pro-
vision for one or two more, by the attach-
ment of a rumble seat in the rear.

Rocker Arm: A pivoted lever used to oper-
ate overhead valves in a T-head motor.

Rod, Radius: See "Radius Rod".

Rod, Steering: See "Steering Rod".

Roller Bearings: See "Bearing, Roller".

Roller Chain: A chain whose links are pro-
vided with small rollers to decrease the mo-
tion and the noise.

Rotary Valve: A type of valve somewhat
similar to the Corliss engine valve used on
automobile motors.

Rumble: A small single seat to provide for
an extra passenger on a two-seated vehicle.
Usually detachable.

Runabout: A small two-seated vehicle, usu-
ally of a lower power and lower speed, as
well as lower operating radius, than a road-
ster.

381

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GLOSSARY

Running Board: A horizontal step placed
below the frame and used to assist passen-
gers in leaving and entering a motor car.

Running Gear: The frame, springs, motor,
wheels, speed-change gears, axles, and
machinery of an automobile, without the
body; used synonymously with chassis.

Safety Plug: See "Fusible Plug".

Safety Valve: A valve seated on the top of a
steam boiler, and loaded so that when the
pressure of the steam exceeds a certain point
the valve is lifted from the seat and allows
the steam to escape.

Saturated Steam: The quality of the
steam when no more steam can be made in
the closed vessel without raising the tempera-
ture or lowering the pressure.

Scavenging: The action of clearing the cyl-
inder of an internal-combustion motor of
the burned-out gases.

Score: To burn, or abrade a moving part
with another moving part.

Screw: An inclined plane wrapped around a
cylinder; a cylinder having a helical groove
cut in its surface.

Searchlight: A headlight designed to throw
a very bright light on the road. Electricity
or acetylene is usually used as an illuminant,
and the lamp has a parabolic reflector and
may be turned to throw the light in any
direction.

Secondary Battery: See "Accumulator".

Secondary Circuit: A circuit in which the
electromotive force is generated by induc-
tion from a primary circuit in which a varia-
ble current is flowing. The high-tension
circuit of a jump-spark ignition system.

Secondary Circuit : The circuit which carries
high-tension current.

Secondary Spark Coll: An induction coil
having a double winding upon its core.
The inner winding is composed of a few
layers of insulated wire of large size, and
the outer winding consists of a great many
layers of very small insulated copper wire.
Also known as a jump-spark coil.

Seize: Refers to moving parts which adhere
because of operation without a film of oil
between the working surfaces.

Selective Change-Speed Gears: Change-
speed gears sO arranged that any desired
speed combination can be obtained without
going through the intermediate steps.

Self -Firing: Ignition of the mixture in a
gas engine due to the walls of the cylinder or
particles attached to them becoming over-
heated and incandescent.

Self-Starter: See "Engine Starter".

Separator, Steam: A device attached to
steam pipes to separate entrained water
from live steam before it enters the engine,
or to separate the oily particles from exhaust
steam on its way to the condenser.

Series Circuit : A compound circuit in which
the separate sources or the separate elec-
trical receiving devices, or both, are so
placed that the current supplied by each, or
passed through each, passes successively
through the other circuits from the first to
the last.

Set Screw: A small screw with a pointed
end used for locking a part in a fixed position
to prevent it from turning.

Setting Valves: See "Valve Setting**.

Shaft, Intermediate: The shaft placed
between the first and third motion gearing
and acting as a carrier of motion between
the two.

Shaft Drive: System of power transmission
by means of a shaft.

Shim: See "Liner".

Shock Absorber: A device attached to the
springs or hangers of motor cars to decrease
the jars due to rough roads, instead of
allowing them to be transmitted to the
frame of the carriage.

Short Circuit: A shunt or by-path of com-
paratively small resistance around a portion
of an electric circuit, by which enough cur-
rent passes through the new path to virtu-
ally cut out the part of the circuit a around
which it is passed, and prevent it from
receiving any appreciable current.

Sight Feed: An indicator covered with glass
which shows that oil is flowing in a system.
A telltale sight. A check on the oiling
system.

Side- Bar Steering: See "Steering, Side-
Bar".

Side-SUpping: See "Skidding**.

Silencer: See "Muffler, Exhaust*'.

Silent Chain: A form of driving chain in
which the links are comprised of sections
which so move over the sprocket that prac-
tically all noise is eliminated. Silent chains
are used specially for driving timing gears,
gearsets, etc.

Skidding: The tendency of the rear wheels
to slide sideways to the direction of travel,
owing to the slight adhesion between tires
and the surface of the roadbed, also called
side-slippinj.

Skip: See "Miss".

Sleeve Valve: A form of valve consisting of
cylindrical shells moving up and down in
the cylinders of such a motor as the Silent
Knight.

Sliding Gears: A change-speed set in which
various gears are placed into mesh by the
sliding on a shaft of one or more gears.

Sliding Sleeve: See "Motor, Sleeve- Valve**.

Slip Cover: A fabric covering for the top
when down or for the upholstery of a motor
vehicle.

Smoke in Exhaust: Smoky appearance in
the exhaust due to too much oil, too rich
mixture, low grade of fuel, or faulty ignition.

Solid Tire: See "Tire, Solid".

Sooting of Spark Plug: Fouling of the
spark plug with soot, due to poor mixture,
impure fuel, or improper lubrication.

Spare Wheel: An extra wheel complete
with inflated tire, carried on the car for quick
replacement of wheel with damaged tire.

Spark, Advancing: See "Advanced Igni-
tion".

Spark Coil: A coil or coils of wire for pro-
ducing a spark at the spark plug. It may
be either a secondary or primary spark coil.

Spark Gap: A break in the circuit of a
jump-spur k ignition system for producing a
spark within the cylinder to ignite the
charge. The spark gap is at the end of a
small plug called the spark plug.

Spark Gap, Extra; See "Spark Gap, Out-
side",

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GLOSSARY

Spark Gap, Outside: A device to overcome
the short circuiting in the spark gap due to
fouling and carbon deposits between the
points of the high-tension spark plug. It is
a form of condenser, or capacity in which
the air acts as the dielectric between two
surfaces at the terminals of a gap in a high-
tension circuit.

Spark Intenslfier: See "Spark Gap, Out-
side".

Spark Lever: See "Timing Lever".

Spark Plug: The terminals of the secondary
circuit of a jump-spark ignition system
mounted to leave a spark gap between the
terminals projecting inside the cylinder for
the purpose of igniting the fuel in the cylin-
der by means of a spark crossing the gap
between them.

Spark Plug, Pocketing: Mounting the
spark plug in a recess of the cylinder head to
reduce the sooting of the sparking points.

Spark Plug, Sooting of: See "Sooting of
Spark Plug".

Spark Regulator: A mechanism by which
the time of ignition of the charge is varied
by a small handle on or near the steering
wheel.

Spark, Retarding: See "Ignition, Retard-
ing".

Spark Timer: See "Timer, Ignition".

Speaking Tube: See "Annunciator".

Specific Gravity: The weight of a. given
substance relative to that of an equal bulk
of some other substance which is taken as a
standard of comparison. Air or hydrogen
is the standard for gases, and water is the
standard for liquids and solids.

Specific Heat: The capacity of a substance
for removing heat as compared with that of
another which is taken as a standard. The
standard is generally water.

Speed-Change Gear: A device whereby the
speed ratio of the engine and driving wheels
of the car is varied.

Speed Indicator: An instrument for show-
ing the velocity of the car.

Speedometer: A device used on motor cars
for recording the miles traveled and for
indicating the speed at all times.

Speedometer Gears: Gears used to drive a
shaft which operates the speedometer.

Speedometer Shaft: A flexible shaft which
operates a speedometer.

Spiral Gear: A gear with helically-cut
teeth.

Splash Lubrication: See "Lubrication,

Splash".
Spline: A key.

Spontaneous Ignition: See "Self-Firing".
Sprag: A device to be let down (usually at

the rear of the car) to prevent its slipping

back when climbing a hill.

Spray Nozzle: That portion of a carbureter
which sprays the gasoline.

Spring: An elastic body, as a steel rod,
plate, or coil, used to receive and impart
power, regulate motion, or diminish con-
cussion.

Spring, Cantilever: A type of spring which
appears like a semi-elliptic reversed; and
which is flexibly attached in the center,
rigidly at one end, and by a shackle at the
other.

Spring, Elliptic: A spring, elliptic in shape,
and consisting of two half-elliptic members
attached together.

Spring Semi-Elliptic: A spring made up ot
a number of leaves, the whole resembling a
portion of an ellipse.

Spring, Supplementary: See "Shock Ab-
sorber".

Spring, Underslung: A spring which is
fastened under the axle instead of over it. .

Spring Hangers: 8ee "Body Hangers".

Spring Shackle: A link attached to one end
of a spring which allows for flattening of the
spring.

Sprocket: A wheel with teeth around the
circumference, so shaped that the teeth will
fit into the links of a chain which drives or
is driven by the sprocket.

Starboard: The right-hand side of a ship or
vessel.

Starter, Engine: See "Engine Starter".

Starting, Gas Engine: The operation neces-
sary to make the engine automatically con-
tinue its cycle of events. It usually consists
of opening the throttle, retarding the spark,
closing the ignition circuit, and cranking the
engine.

Starting Crank: A crank by which the
engine may be given several revolutions by
hand in order to start it.

Starting Device: See "Engine Starter".

Starting on Spark: In engines having four
or more cylinders with well-fitting pistons,
it is often possible to start the motor after it
has stood idle for some time by simply clos-
ing the ignition circuit, provided that the
previous stopping of the engine was done
by opening the ignition circuit before the
throttle was closed, leaving an unexploded
charge under compression in one of the
cylinders.

Steam: The vapor of water; the hot invisible
vapor given off by water at its boiling point.

Steam Boiler: See "Boiler".

Steam Condenser: See "Condenser".

Steam, Cycle of: A series of operations of
steam forming a closed circuit, a fresh series
beginning where another ends; that is,
steam is generated in the boilers, passes
through the pipes of the engine, doing work
successively in its various cylinders, escap-
ing at exhaust pressure to the condenser,
where it is converted into water and returned
to the boiler, to go through the same opera-
tions once more.

Steam Engine: A motor depending for its
operation on the latent energy in steam.

Steam Gage: See "Pressure Gage".

Steam Port: See "Admission".

Steering, Side-Bar: Method of guiding the
car by means of an upright bar at the side
of the seat.

Steering Angle for Front Wheels: Maxi-
mum angle of front wheels to the axle when
making a turn; should be about 35°.

Steering Check: A device for locking the
steering gear so that the direction will
not be changed unless desired.

Steering Column: See "Steering Post".

Steering Gear: The mechanism by which
motion ia communicated to the front axle of
the vehicle, by which the wheels may be
turned to guide the car as desired.

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GLOSSARY

Steering Knuckle: A knuckle connecting
the steeling rods with the front axle of the
motor.

Steering Lever: A lever or handle by which
the car is guided.

Steering Neck: The vertical spindle carried
by the steering yoke. It is the pivot of the
bell crank by which the wheel is turned.

Steering Pillar: See "Steering Post".

Steering Poet: The member through which
the twist of the steering wheel is trans-
mitted to the steering knuckle. The steering
post often carries the spark and throttle
levers also.

Steeling Rod: The rod which connects the
steering gear with the bell cranks or pivot
arms, by means of which the motor car is
guided.

Steering Wheel: The wheel by which the
driver of a motor car guides it.

Steering Yoke: The Y-shaped piece in
which the front axle terminates. The yoke
carries the vertical steering spindle or
steering neck.

Stephenson Link Motion: A reversing gear
in which the ends of the two eccentric rods
are connected by a link or quadrant sliding
over a block at the end of the valve spindle.

Step-Up Coll: A coil used to transform low-
into high-tension current.

Storage Battery: See "Accumulator".

Stroke: See "Piston Stroke".

Strainer, Gasoline: A wire netting for pre-
venting impurities entering the gasoline feed
system.

Strangle Tube: The narrowing of the
throat of the carbureter just above the air
inlets in order to increase the speed of the
air, and thus increase the proportion of gas
which will be picked up.

Stroke: The distance of travel of a piston
from its point of farthest travel at one end
of the cylinder to its point of farthest travel
at the other end. Two strokes of the piston
take place to every revolution of the crank-
shaft.

Stud Plate: The plate or frame in a planet-
ary transmission system carrying studs upon
which the central pinions revolve.

Suction Valve: The type of admission valve
on an internal combustion engine which is
opened by the suction of the piston within
the cylinder and admits the mixture. The
valve is normally held to its seat by a spring.

Sulpha ting of Battery: The formation of
an inactive coating of lead sulphate on the
surface of the plates of a storage battery.
It is a source of loss in the battery.

Superheated Steam: Steam which has been
still further heated after reaching the point
of saturation.

Supplementary Air Valve: See "Auxiliary
Air Valve".

Swivel Joint: The joint for connecting the
steering arm of the wheel or lever-steering
mechanism to the arms on the steering
wheel. Also called knuckle joint.

Tachometer: An instrument for indicating
the number of revolutions made by a machine
in a unit of time.

Tandem Engine: A compound engine hav-
ing two or more cylinders in a line, one

behind the other, and with pistons attached
to the same piston rod.

Tank Gage: See "Fuel-Level Indicator".

Tappet Rod: See "Push Rod".

Taxlcab: A public motor-driven vehicle in
which the fare is automatically registered by
the taximeter.

Taximeter: An instrument in a public
vehicle for mechanically indicating the fare
charged.

Terminals: The connecting posts of elec-
trical devices, as batteries or coils.

Thermal Unit: Usually called the British
Thermal Unit, or B. t. u. A measure of
mechanical work equal to the energy re-

auired to raise one pound of water one
egree Fahrenheit.

Thermostat: An instrument to automati-
cally regulate the temperature.

Thermoelphon Cooling: A method of cool-
ing the cylinder of a gas engine. The water
rises from the jackets and siphons into a
radiator from whence it returns to the
supply tank, doing away with the necessity
for a circulating pump.

Three-Point Suspension: A method used
for suspending motor car units, such as the
motor, on three points.

Throttle: A valve placed in the admission
pipe between the carbureter and the admis-
sion valve of the motor to control the speed
and power of the motor by varying the
supply of the mixture.

Throttle, Foot: See "Accelerator".

Throttle, Lever: A lever on the steering
wheel which operates the carbureter throttle.
See "Throttle''.

Throttling: The act of closing the admistuon
pipe of the engine so that the gas or steam is
admitted to the cylinder less rapidly, thus
cutting down the speed and power of the
engine.

Thrust Bearing: A bearing which takes
loads parallel with the axis of rotation of the
shaft upon which it is fitted.

Tickler: A pin in a carbureter arranged to
hold down the float in priming, also called
flushing pin and primer.

Timer, Ignition: An ignition commutator.

Timing Gears: The gears which operate the
camshaft and magneto shaft. The camshaft
gear is twice as large as the crankshaft gear.

Timing Lever: A lever fitted to gas engines
by means of which the time of ignition is
changed. Also called spark leper.

Timing Valve: In a gas engine using float-
tube ignition, a valve controlling the opening
between the combustion space and the
igniter.

Tip, Burner: A small earthen, aluminum, or
platinum cover for the end of the burner
tube of an acetylene lamp. It is usually
provided with two holes, so placed that the
jets from them meet and spread out in a
fan shape.

Tire, Airless: See "Airless Tire".

Tire, Clincher: A type of pneumatic tire
which is held to a clincher.

Tire, Cushion: Vehicle tire having a very
thick rubber casing and very small air space.
It is non-puncturable and does not have to
be inflated, but is not as resilient as a pneu-
matic tire.

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GLOSSARY

Tire, Non-Delia table: See "Tire, Non-
Puncturable".

Tire, Non Pu net urable: A tire so construct-
ed that it cannot be easily punctured or will
not become deflated when punctured.

lire. Punctures in: Holes or leaks in pneu-
matic tires caused by foreign substances
penetrating the inner tube and allowing the
air to escape.

Tire, Single-Tube: A pneumatic tire in
which the inner and outer tubes are com-
bined.

lire. Solid: A tire made of solid, or nearly
solid rubber.

Tire Band: A band to protect or repair a
damaged pneumatic tire. See "Tire Pro-
tector*.

Tire Bead: Lower edges of a pneumatic tire
which grip the curved portion of a rim.

Tire Case: (1) A leather or metal case for
carrying spare tire; same as tire holder,
(2) The outer tube.

Tire Chain: See "Anti-Skid Device".

Tire Filling: Material to be introduced into
the tire to take the place of air and do away
with puncture troubles

lire Gage: Gage used for measuring the air
pressure in a pneumatic tire.

lire Holder: A metal or leather case for
carrying spare tires.

Tire-Inflating Tank: A tank containing
compressed air or gas for inflating the tires.

lire Inflater, Mechanical : A small mechan-
ical pump for inflating pneumatic tires.

Tire Patch: See "Patch, Tire Repair".

Tire-Pressure Gage: A pressure gage to
indicate the pressure of air in the tire.

Tire Protector: The sleeve or band placed
over a tire to protect it from road wear.

Tire Pump: A pump for furnishing air under
pressure to the tire, may be either hand- or
power-operated.

Tire Sleeve: A sleeve to protect the injured
part of a pneumatic tire. It is a tire pro-
tector which covers more of the circumfer-
ence of the wheel than a tire band. See
"Tire Protector".

Tire Tape: Adhesive tape used to bind the
outer tube to the rim in repairing tires.

Tire Tool: Tool used to apply and remove a
tire.

Tire Valve: A small valve in the inner tube

to allow air to be pumped into the tube

without permitting it to escape.
Tires, Creeping of: See "Creeping of Tires".
Tonneau: The rear seats of a motor car.

Literally, the word means a round tank or

water barrel.
Torque: Turning effort, or twisting effort of

a rotating part.

Torque Rod: A rod attached at one end to
the rear axle and at the other to the frame;
used to prevent twisting of the rear-axle
housing.

Torsion Rod: The shaft that transmits the
turning impulse from the change gears to
the rear axle. Usually spoken of as the
ehafl.

Touch Spark: See "Wipe Spark".

Tourabout: A light type of touring car.

Touring Car: A car with no removable rear

seats, and a carrying capacity of four to
seven persons.

Town Car: A car having the rear seats
enclosed but the driver exposed.

Traction: The act of drawing or state of
being drawn. The pull (or push) of wheels.

Tractor: A self propelled vehicle for hauling
other vehicles or implements; a traction
engine.

Transmission, Individual Clutch: - A
transmission consisting of a set of spur gears
on parallel shafts which are always in mesh,
different trains being picked up with a
separate clutch for each set.

Transmission, Planetary: A transmission
system in which a number of pinions revolve
about a central pinion in a manner similar to
the revolution of the planets about the sun;
usual type consists of a central pinion sur-
rounded by three or more pinions and an
internal gear.

Transmission, Sliding Gear: A trans-
mission system in which sliding change-speed
gears are used.

Transmission Brake: Brake operating on
the gearset shaft or end of the propeller shaft.

Transmission Gears: A set of gears by
which power is transmitted. In automo-
biles, usually called change-epeed gears.

Transmission Ratio: .The ratio of the speed
of the crankshaft to the speed of the trans-
mission shaft or driving shaft.

Tread: That part of a wheel which comes in
contact with the road.

Tread, Detachable: A tire covering to pro-
tect the outer tube, which may be taken off
or replaced.

Trembler: The vibrating spring actuated by
the induction coil magnet which rapidly
connects and disconnects the primary circuit
in connection with jump-spark ignition.

Truck: (1) A strong, comparatively slow-
speed vehicle, designed for transporting
heavy loads. (2) A swiveling carriage
having small wheels, which may be placed
under the wheels of a car.

Try Cock: A faucet or valve which may be
opened by hand to ascertain the height of
water in the boiler.

Tube Case: See "Tire Case".
Tube Ignition: See "Hot-Tube Ignition".
Tubing, Flexible: See "Flexible Tubing".
Tubular Radiator: An automobile radiator

in which the jacket water circulates in a

series of tubes.

Tungsten Lamp: Incandescent bulb with
the filament made of tungsten wire.

Turning Moment: See "Torque".

Turning Radius: The radius of a circle
which the wheels of a car describe in making
its shortest turn.

Turntable: Device installed in the floor of a
garage and used for turning motor cars
around.

Two-Cycle or Two-Stroke Cycle Engine:

An internal-combustion engine in which an
impulse occurs at the beginning of every
revolution, that is, at the beginning of every
downward stroke of the piston.

Two- to-One Gear: The system of gearing in
a four-cycle gas engine for driving the cam-
shaft, which must revolve once to every two
revolutions of the crankshaft.

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GLOSSARY

Under Frame: The main frame of the
chassis or running gear of a motor vehicle.

Unit -Power Plant: A power system consist-
ing of a motor, gearset, and clutch which
may be removed from the motor car as a
unit.

Universal Joint: A mechanism for endwise
connection of two shafts so that rotary
motion may be transmitted when one shaft
is at an angle with the other. Also called
universal coupling, flexible coupling, Cardan
joint and Hooke's joint.

Upkeep: The expenditure for maintenance
or expenditure required to keep a vehicle in
good condition and repair.

Vacuum Fuel Feed : A system of feeding the
gasoline from a tank at the rear of an auto-
mobile by maintaining a partial vacuum at
some point in the system, usually at the dash,
the fuel flowing from this point by gravity to
the carbureter.

Vacuum Line: In an indicator diagram, the
line of absolute vacuum. It is at a distance
corresponding to 14.7 pounds below the
atmospheric line.

Valve: A device in a passage by which the
flow of liquids or gases may be permitted or
stopped.

Valve, Admission : The valve in the admis-
sion pipe of the engine leading from the car-
bureter to the cylinder by which the supply
of fuel may be cut off.

Valve, Automatic: See "Automatic Valve".
Valve, Inlet: See "Inlet Valve".
Valve, Mixing: See "Mixing Valve".
Valve, Muflaer Gut-Out: See "Cut-Out.
Muffler".

Valve, Overhead: See "Overhead Valve".

Valve, Poppet: See "Poppet Valve".

Valve, Rotary: See "Motor, Rotary Valve"-

Valve, Suction: An admission valve which
is opened by the difference between the pres-
sures in the atmosphere and in the cylinder.

Valve Cage: A valve-retaining pocket which
is attached to the cylinder.

Valve Clearance: The clearance of play
between the valve stem and the tappet.

Valve Gear: The mechanism by which the
motion of the admission or exhaust valve is
controlled.

Valve Grinding: The act of removing marks
of corrosion, pitting, etc., from the seats and
faces of poppet or disk valves. The surfaces
to be ground are rotated in contact with each
other, an abrasive having been supplied.

Valve Lift: See "Lift".

Valve Lifter: A device for raising a poppet

valve from its seat.
Valve Seat: (1) That>portion of the engine

upon which the valve rests when it is closed.

(2) The portion upon which the face of a

valve is in contact when closed.
Valve Setting: The operation of adjusting

the valves of an engine so that the events of

the cycle occur at the proper time. Also

called valve timing.
Valve Spring: The spring which is around

the valve stem and is used to return the

valve to closed position after it has been
opened by the cam:

Valve Stem : The rod-like portion of a poppet
valve. *~*rwr-

Valve Timing: See "Valve Setting".

Vaporizer: A device to vaporise the fuel for
an oil engine. In starting it is necessary to
heat the vaporizer, but the exhaust gaae*
afterwards keep it at the proper tempera-
ture. The carbureter of the gas engine
properly belongs under the general head of
vaporizer, but the term has become restricted
to the vaporiser for oil engines.

Variable-Speed Device: See "Gear, Change-
Speed".

Vertical Motor: An upright engine whose
piston travel is in a vertical plane.

Vibrator: The part of the primary circuit of
a jump-epark ignition system by which the
circuit is rapidly interrupted to give a trans-
former effect in the coil.

Vibrator, Master: See "Master Vibrator".

Volatile: Passing easily from a liquid to a
gaseous state, in opposition to fixed.

Volatilization: Evaporation of liquids upon
exposure to the air at ordinary temperatures.

Volt: Practical unit of electromotive force -
such an electromotive force as would cause
a current of one ampere to flow through a
resistance of one ohm.

Voltammeter: A voltmeter and an ammeter
combined; sometimes refers to wattmeter.

Voltmeter: An instrument for measuring
the difference of electric potential between
the terminals of an electric circuit. It
registers the electric pressure in volts.

Vulcanization: The operation of combining
sulphur with rubber at a high temperature
either to make it soft, pliable, and elastic, or
to harden it.

Vulcanizer: A furnace for the vulcanisation
of rubber.

Walking Beam: See "Rocker Arm".

Water Cooling: Method of removing the
heat of an internal-combustion motor from
the cylinders by means of a circulation of
water between the cylinders and the outer
casing.

Wa ,5 er . Gage: An instrument used to indicate
the height of water within a boiler or other
water system. It consists of a glass tube
connected at its upper and lower ends with
the water system.

Water Jacket: A casing placed about the
cylinder of an internal-combustion engine to
permit a current of water to flow around it
for cooling purposes.

Watt: The unit of electric power. It is the
product of the current in amperes flowing in

a circuit by the pressure in volts. It is -—

74d
of a horsepower.
Watt Hour: The unit of electrical energy.
The given watt-hour capacity of a battery,
for instance, means the ability of a battery
to furnish one watt for the given number of
hours or the given number of watts for one
hour, or a number of watts for a number of
hours such that their product will be the
given watt hours.

Welding, Autogeneous: A method of joining
two pieces of metal by melting by means of a

386

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GLOSSARY

blow torch burning acetylene in an atmos-
phere of oxygen. This melts the ends of the
parts and these are then run together.
Wheel, Artillery: A wood-spoked wheel
whose spokes are in line with a line drawn
vertically through the hub.
Wheel, Dished: A wheel made concave or
convex so that the hub is inside or outside as
compared with the rim. This is to counter-
act the outward inclination of the wheel due
to the fact that the spindle is tapered and
that its outward center is lower than its
inner center.
Wheel, Double-Interacting: The mecha-
nism by which two wheels are hung on one
hub or axle, the outer being shod with an
ordinary solid tire and the inner with a
pneumatic tire, so that the weight of the
vehicle bears against the lowest point of the
pneumatic tire of the inner wheel to give the
durability and tractive properties of a solid
tire with the resiliency of a pneumatic.
Wheel, Spare: See "Spare Wheel".
Wheel Steering: See "Steering Wheel".
Wheel, Wire: A wheel with spokes made of

wire.
Wheel Puller: A device used for pulling

automobile wheels from their axles.
Wheel Steer: A method of guiding a car by

means of a hand wheel.
Wheel, Steering Angle for: Tho angle
which the steering column makes with the
horizontal. It varies from 90° to 30° or less.
Wheelbase: The distance between the road
contact of one rear wheel with the point of
road contact of the front wheel on the same
side.
Wheels, Driving on All Four: The method
of using all four wheels of an automobile aa
the driving wheels.
Wheels, Driving on Front: The method of

using the two front wheels as the drivers.
Wheels, Steering on Rear: Method of
guiding the vehicle by turning the rear
wheels.

Whistle: An automobile accessory consisting
of a signalling apparatus giving a loud or
harsh sound. Also called a horn.

Wind Guard: See "Wind Shield".

Wind Shield: A glass front placed upright
on the dash to protect the occupants of the
car from the wind.

Wipe Spark: Form of primary sparking
device in which a spark is produced by a
moving terminal sliding over another ter-
minal, the break thus made causing a spark.
Also called touch spark.

Wipe-Spark Coil: A primary spark coil
with which the spark is made by wiping
contact.

Wire Drawing: The effect of steam passing
through a partially closed valve or other
constricted opening; so called from the thin-
ness of the indicator diagram.

Working Pressure: The safe working pres-
sure of a boiler, usually estimated as ft of
the pressure at which a boiler will burst.

Worm : A helical screw thread.

Worm and Sector: A worm gear in which

the worm wheel is not complete but is only

a sector. Used especially in steering

devices.
Worm Drive: A form of drive using worm

gears. See "Gears, Worm".
Worm Gear: The spiral gear in which a

worm or screw is used to rotate a wheel.
Worm Wheel: A wheel rotated by a worm.
Wrist Pin: See "Piston Pin".

X Spring: A vehicle spring composed of two
laminated springs so placed one upon the
other that they form the letter X.

Yorke, Steering: See "Steering Yoke"

387

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REVIEW QUESTIONS

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REVIEW QUESTIONS

ON THE SUBJECT OF

ELECTRIC AUTOMOBILES

PART I

1. Why is the Edison battery of special interest?

2. What are the advantages of a series-wound motor?

3. Why is the electric automobile essentially a pleasure vehicle?

4. Give a description of the construction of the Edison nega-
tive plate.

5. Describe the drum type of controller.

6. What is the standard unit for measuring the capacity of
a storage cell?

7. What is the strongest recommendation for an electric car?

8. Make a control wiring diagram.

9. Give a short description of the Arrol-Johnston electric car.

10. Describe the positive plate of the Ironclad Exide type.

11. What are the essentials of an electric motor?

12. State the advantages of worm-gear transmission.

13. What is the office of a shunt?

14. Of what is a battery composed?

15. What are the advantages and disadvantages of Edison
storage batteries?

16. How is counter-e.m.f. developed in an electric motor?

17. What is the office of a fuse?

391

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REVIEW QUESTIONS

ON THE SUBJECT OF

ELECTRIC AUTOMOBILES

PART II

1. At what temperature will an electrolyte freeze which has
a specific gravity of 1.210?

2. What parts of an electric motor are subject to wear?

3. Which is the corresponding specific gravity for 30° Baume?

4. What is one of the commonest ways of abusing a battery?

5. By what is the power of an electric vehicle limited?

6. What is the lowest limit to which a battery could be dis-
charged?

7. Describe the Fritchle Milostat.

8. Why are solid rubber tires adaptable to electric cars?

9. What should be the specific gravity of the electrolyte when
fully charged?

10. Describe the automatic charge-stopping device.

11. The price of one kilowatt of electricity for charging storage
batteries is 7 cents; what will 76,560 watts cost?

12. State the constituents of the electrolyte and their pro-
portion.

13. State the cause of low battery power.

14. Discuss the danger of overcharging.

15. What are the dangers of sulphating and how can we guard
against it?

16. Describe the different steps necessary in starting an electric
car.

17. State the most important point to be observed in the care
of the battery.

392

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REVIEW QUESTIONS

ON THE SUBJECT OF

STEAM AUTOMOBILES

1. Define radiation, absorption, conduction, and convection.

2. What is absolute zero? What molecular state does it
theoretically represent?

3. Discuss the location of the steam engine on automobiles.

4. Convert 65 degrees Fahrenheit into centigrade.

5. State Boyle's Law.

6. Define force, work, power, and horsepower.

7. Describe and sketch the action of an elementary slide
valve.

8. Define British thermal unit.

9. Draw a theoretical indicator card for one-fourth cut-off.

10. • Define latent heat. How many British thermal units are
absorbed in boiling away a pound of water at atmospheric pressure?

11. Discuss the effect of compression on the indicator card of
an engine.

12. Why is the explosion of a stationary boiler so destructive?

13. Define superheat. What is its object?

14. What is the purpose of condensers if used on steam cars?

15. Describe and sketch the Stephenson link valve motion.

16. Describe the Bunsen burner.

17. What is the object of the pilot light?

18. Describe the Ofeldt burner.

19. How are automobile boilers classified?

20. Explain the principles of the fire-tube boiler.

21. In what way do flash boilers differ from the other types?

22. For what purpose are check valves used; how are they
constructed?

393

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REVIEW QUESTIONS

ON THE SUBJECT OF

COMMERCIAL VEHICLES

1. Classify commercial vehicles as to power used.

2. State briefly the advantages of the electric.

3. What methods of motor suspension are used on light shaft-
driven delivery cars?

4. Describe rear-axle construction of the 2-ton Commercial.

5. What are the peculiar advantages of the Couple-Gear
truck?

6. What transmission is used on the Walker electric?

7. Why are safety devices installed on most all up-to-date
trucks? Describe action of the charging circuit-breaker.

8. Where is the controller located in the Baker?

9. How many plates are used per cell in light delivery wagons?

10. What are the dimensions and horsepower of motor used on
the Autocar delivery wagon?

11. Give bore and stroke of motors used on the White 5-ton
trucks; on the Pierce Arrow; on the Locomobile; on the Vulcan.

12. What type of radiator is usually used on trucks; why is it
used?

13. Sketch the White sight-feed lubricating system.

14. Explain the action of the Pierce centrifugal motor governor.

15. Describe the Jeffery Quad.

16. Explain the principle of compensating spring support.

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GENERAL INDEX

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GENERAL INDEX

In this Index the Volume number appears in roman numerals — thus:
I, II, III, IV, etc., and the Page number in Arabic numerals— thus:
1, 2, 3, 4, etc. For example: Volume IV, Page 327, is written, IV, 327.

The page numbers of this volume will be found at the bottom of the pages;
the numbers at the top refer only to the section.

Vol. Page

A. C. rectifiers

IV,

241

Accurate filing in automobile

repair shop

361

draw filing

362

filing to a micrometer fit

II,

362

revolving filing

II,

363

use of safe edges

II,

361

Accessories for gasoline truck

motors

304

carburetors

304

cooling systems

305

ignition

304

lubrication

307

Action of storage cell on charge

IV,

195

Action of storage cell on discharge IV,

196

Action of steering-gear wheels on

turning

II,

Adjusting annular bearings

435

Adjusting clutch pedals

392

Adjusting fans

316

Adjusting pumps

317

Adjusting spring hangers

II,

110

Adjusting specific gravity of

electrolyte

IV,

206

Adjusting tension of valves

271

Adjustment of air and gasoline sup-

ply in carburetors

116

auxiliary air valve

117

double carburetors for multi-c>

lin-

der motors

121

double-nozzle carburetors

119

multiple nozzle carburetors

122

Vol. Page
Adjustment of air and gasoline sup-
ply in carburetors
(continued)
nature of new developments in

carburetors
use of by-pass
usual forms of auxiliary air-inlet

valve
Venturi-tube mixing chamber
water-jacketing
Adjustment of connecting-rod bear-
ings
babbitting bearings
drilling thin shims
kinks in adjusting-bearings
mandrel for lapping
special sleeve replaces shims
Adjustment of carburetor nozzle
Advance and retard ignition adjust-
ments III
adjust ing for time factor of coil III
analysis of oscillograph

diagrams
calculation of small time allow-
ance
magneto timing
Mca method of advancing
spark
Advantages of boosting in charging

batteries V

Advantages of electric transmission

in motor trucks V, 335

III

III
III

III

120
120

117
118
116

79
79
82
79
82
81
210

139
140

144

140
142

145

108

Note. — For page numbers see foot of pages.

397

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INDEX

Vol. Page

Advantages of oxy-acetylene wcld-

Vol. Page
Automatic engagement devices for

ing process

IV,

403

electric starters

Air-cooling system for motors

314

(continued)

air jackets

315

Bendix drive III,

309

,348

blowers and fans

315

Bosch-Rushmore type

III,

309

flanges or fins

314

Automatically timed systems

III,

14$

internal cooling and scavenging I,

315

. Eisemann centrifugal-governor

Air leaks in manifold of motor-

type

III,

149

cycle

IV,

390

Herz ball-governor tyj>e

III,

150

Air-supply system for public

Automobile boilers for steam cars V,

232

garages

338

flash boilers

237

Alignment of front wheels

special types

230

troublesome

water-tube boilers

234

Ammeter, typical

iv,

114

Auto-tractor

352

Ammeter and dash lamp

IV,

138

Auxiliary air valve of carburetor

117

Ampere-hour meter

163

Avery tractor

35S

methods of use

164

Axle bearings

II,

readjusting meter

164

ball bearings

II,

types of instruments

169

classification

11,

Analysis of motorcycle

roller bearings

II,

mechanisms

IV,

343

Axle carrying load and drive

II,

150

Anti-freezing solutions

313

Apparatus for simple welding job IV,

414

Arbor presses and gear pullers

411

Arc welder

Back-firing

IV,

424

apparatus

iv,

413

Back-kick releases

III,

312

graphite electrode

iv,

413

Ball and Ball carburetor

163

metallic electrode

iv,

413

adjustments

165

Architectural appearance of public

pick-up device

165

garage

ii,

323

Ball bearings I, 348

; ii,

Armature of electric vehicle motor V,

Basis of classification of springs

ii,

Armature troubles

adjusting spring hangers

ii,

110

Armature windings

in,

cantilever

ii,

100

Atwater-Kent ignition system

in,

182

full elliptic

ii,

Auburn-Delco starter

in,

334

Hotchkiss drive

ii,

102

Autocar gasoline delivery wagon

295

platform

ii,

Auto-Lite starting and lighting

semi-elliptic

ii,

system

in,

346

shackles and spring horns

ii,

110

Automatic battery cut-out

in,

296

spring construction and

Adlake type

in,

297

materials

ii,

112

Ward-Leonard type

in,

297

spring lubrication

ii,

111

Automatic gear-cutting machines I,

423

spring troubles and remedies

ii,

112

Automatic charge-stopping devit

three-quarter elliptic

ii,

for batteries

unconventional types

ii,

103

Automatic engagement devices for

varying methods of attaching

electric starters

III,

309

springs

ii,

108

Auto-Lite type

III,

309

Battery cut-out III, 350;

iv,

Note. — For page numbers see foot of pages.

398

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INDEX

Vol. Page

Battery equipment for electric cars V, 282

Bearing scraping II, 360

Bearings I, 86, 344

ball bearings I, 348

blearing wear I, 87

combined radial and thrust

bearings I, 351

crankshaft pounding I, 88

holding for bearing caps I, 89

plain bearings I, 345

roller bearings I, 346

test for tightness I, 88
types of bearings required for

different locations I, 344
Becker gear-cutting machine I, 438
Bench work II, 353
bearing scraping II, 366
chipping and filing II, 355
cutting gears II, 406
drilling II, 382
filing methods II, 357
fitting piston rings II, 373
fitting taper pins II, 393
forging II, 401
hand keyseating II, 394
lapping cylinders II, 379
miscellaneous bench methods II, 410
reaming II, 389
rebabbitting bearings II, 364
riveting II, 396
soldering II, 371
tapping II, 385
use of micrometers II, 377
work bench design II, 353
work vises II, 354
Bending oil pipes I, 343
Bennett carburetor I, 197
adjustment I, 200
installation I, 199
kerosene modified adjustments I, 200
Bent needle- valve stem I, 207
Bevel gears I, 442
Bevel type friction disc trans-
mission I, 416
Bijur starting and lighting system III, 355
Bilgram gear-planing machine I, 441
Blacksmi thing repair outfit II, 402

Vol. Page

Blowouts in tire repair II, 261

inside and outside method II, 263

inside repair method II, 262

Boiler accessories and regulation

in steam cars V, 240

check valves V, 240

Doble V, 249

fuel system V, 240

Ofeldt V, 251
Stanley fuel, water and steam

systems V, 241

Boiler and engine types V, 200

Boosting in charging batteries V, 108

advantages of V, 108

methods of V, 111

possible safe charging rates V, 110

regulation of boosting charge V, 109

Boring II, 426

Bosch-Rushmore starting and

lighting system III, 372

Boyle's law V, 204

Brake adjustment on gasoline cars II, 181

Brake lubrication on gasoline cars II, 181

Brake linings II, 396

riveting lining II, 306

types of rivets II, 396

Brake troubles and repairs II, 185

dragging brakes II, 185

dummy brake drum useful II, 186

eliminating noises II, 188

stretching brake lining II, 188

stopping brake chattering II, 186

truing brake drums II, 180

Brakes II, 172; IV, 361; V, 287, 339

brake adjustment II, 181

brake lubrication II, 181

brake troubles and repairs II, 185

braking all wheels V, 340

classification II, 173

double brake drum for safety II, 178

electric brakes II, 181

external-contracting brakes II, 173

function of brake II, 172

hydraulic brakes II, 182

internal-expanding brakes II, 174

methods of brake operation II, 178

recent developments II, 181

Note. — For page numbers see foot of pages.

399

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INDEX

Vol. Page

Brakes (continued)

usual types

339

vacuum brakes

11,

183

Braking on all wheels

340

British thermal unit

206

Brown and Sharpe gear-cutting

machine

437

Browne-Branford carburetor

144

Browne carburetor

142

Brushes and commutator of electric

vehicle motor

154

Buick-Delco type of starter

III,

330

Building materials for public

garages

II,

321

availability

II,

322

fireproof

II,

322

first cost

II,

321

Burner principles

227

Bunsen burner

227

modifications for automobile

work V, 227

Burning hole in metal in welding IV, 431

Bushing removers I, 66

Cable and rope drives I, 416
Cadillac carburetor I, 186
Camber II, 63
Cams I, 246
Cantilever spring II, 100
Capacity of battery IV, 197
Capacity of condensers III, 39
Carburetor operation and adjust-
ments I, 122, 209
Ball and Ball carburetor I, 163
Bennett carburetor I, 197
Browne-Branford carburetor I, 144
Browne carburetor I, 142
Cadillac carburetor I, 186
carburetors on Ford cars I, 134
Carter carburetor I, 182
Deppe gas generator I, 204
Edwards carburetor I, 149
foreign kerosene carburetors I, 193
"H. & N." duplex carburetor I, 201
Holley carburetors I, 134, 137, 192
Johnson carburetor I, 179

Note. — For page number 8 tee foot of pages.

Vol. Pap

Carburetor operation and adjust-
ments (continued)
Kingston carburetors I, 134, 139

Longuemare carburetor I, 151

Marvel carburetor I, 169

Master carburetor I, 148, 195

need for heavy fuel carburetors I, 192
Newcomb carburetor I, 166

oxygenerator vaporizing device I, 189
Packard carburetor I, 1S5

Ray field carburetor I, 159

Schebler carburetors I, 172

Senrab carburetor I, 195

Stewart carburetor I, 176

Stromberg carburetors I, 122

Sunderman safety carburetor I, 150

"~ Webber automatic carburetor I, 155
Zenith carburetors I, 127

Carburetor troubles and remedies I, 206
adjustment of nozzle I, 210

bent needle-valve stem I, 207

causes of misfiring I, 215

cleaning the carburetor I, 212

engine should start on first turn I, 206
gasoline strainer a source of

trouble I, 207

pre-heating the air I, 214

smallest detail important I, 213

throttle loose on shaft I, 20S

Carburetors I, 109; IV, 383, 388; V, 304
classification of I, 111

effect of heavier fuels I, 109

floats I, 115

on Ford cars I, 134

function of I, 109

needle valves I, 114

throttle valves I, 113

Carburetors and carburet ion I, 109

adjustment of gasoline supply I, 116
carburetor operation and adjust-
ment I, 122
carburetor troubles and remedies I, 206
kerosene and heavy fuel car-
buretors I, 192

Care of storage battery IV, 200; V, 113
a. c. rectifiers TV, 241

adding acid IV, 201

400

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INDEX

Vol.

Page

Vol.

Page

3are of storage battery (continued)

Carter carburetor

182

adding distilled water

200

Cast aluminum welding

471

adjusting specific gravity

206

after-treatment

IV,

472

charging from outside source

237

aluminum castings

471

charging in series for economy

240

pre-heating

471

cleaning battery IV, 219; V

117

preparation

471

cleaning repairs parts

257

welding process

471

complete renewal of battery

127

Cast axles

detecting deranged cells

IV,

217

Cast-iron welding

IV,

459

equalizing charges necessary

IV,

239

expansion and contraction

IV,

460

gassing

IV,

209

flux

IV,

461

higher charge needed in cold

general considerations

IV,

459

weather

IV,

211

oxidation

IV,

459

how to take readings

IV,

217

pre-heating

IV,

460

hydrometer

IV,

201

preparation of welds

IV,

462

installing new battery

IV,

235

welding process

IV,

463

internal damage

IV,

216

welding rods

IV,

460

joint hydrometer and volt-

Cast-steel wheels on gasoline com

meter test

IV,

218

mercial cars

II,

207

lead burning

IV,

229

Causes of ignition failure

III,

202

methods of charging

IV,

240

failure of current to supply

III,

203

miscellaneous operations

139

short-circuits

III,

202

motoi>generator

IV,

241

weak magnets

III,

203

overhauling battery

IV,

223

Causes of boiler explosions

209

putting battery out of commis

Causes of low battery power

147

Bion

137

Causes of misfiring in engine

215

replacing jar

IV,

220

bent float spindle

216

restoring sulphated battery

IV,

214

carburetion and fuel

215

specific gravity too high

IV,

215

leaky float

216

storing battery

IV,

235

obstructed spraying nozzle

216

sulphating

IV,

212

Causes of variations in ratings of

temperature variations in

truck motors

301

voltage test

IV,

218

Cell types, general characteristics

» v,

to test rate of charge

IV,

249

Centrifugal type of motor governor V,

309

to test rate of discharge

246

Central location for public garage

II,

284

voltage tests

IV,

253

Chain drive

why starting is harder in cold

for camshafts

278

weather

244

Chain-driven Genemotor

100

Care of burner on steam cars

261

mounting starter

100

Care of engine bearings

260

operation

104

Care and operation of electrics

wiring

103

care of battery

113

Changes in construction of manifold I

222

charging battery

Changing tires, gasoline cars

218

electric indicating instruments

interchangeable Continental

and their uses

163

tires

220

some sources of power loss

150

interchangeable Michelin tires

219

tires and mileage

156

possible tire changes

219

Note. — For page numbers see foot of pages.

401

Vol.
V
V
V
IV
V

Charging battery

boosting

method of

outside source

sources of charging current
Charging an Edison battery
Charging process after washing

battery
Charging rate of batteries
Chassis group

characteristics of parts

frames

shock absorbers

springs
Checking up Ford axles
Chemical effect of current
Check valves
Chemical action on charging

battery plate
Chemical sources of current

primary -batteries

storage cells
Chevrolet-Auto-Lite starting and

lighting type III

Chipping and filing in automobile
repair

chipping

chisels

chisel types
Circuit-breaker III, 298,

Circuits III, 21

V
V
II
II
II
II
II
II
III
V ;

V
III
III
III

multiple or shunt circuit

Series circuit

series-multiple circuit
Circulation, water

Cadillac system

pumps

thermosiphon
Classification of

axle bearings

carburetors

connecting-rod troubles

engine operation principles

final drive

gasoline automobiles

generators

pneumatic tires

III
III
III

I
I

III

INDEX

Page Vol. Page

87 Classification of (continued)

108 rear axles II, 149

93 tire troubles II, 260

237 types of front axles II, 57 «

87 Cleaning I, 316

107 aluminum I, 98

camshaft gears I, 284

121 carburetor I, 212

96 chains IV, 396

74 cylinder after grinding in

74 automobile repair II, 382

75 files in automobile repair shop II, 363
115 repair parts IV, 257

96 transmission gears I, 428

171 Cleaning and fitting connecting-rod

29 bearings II, 367

240 cleaning parts II, 367

cutting-in bearing II, 368

25 filing shims II, 368

96 scraping process II, 368

96 Cleaning or washing a battery V, 117

97 charging process after washing

battery V, 121

334 materials to have on hand V, 119

replacing a defective jar V, 123

355 treating the plates V, 119

357 washing or renewing separators

355 and assembly cells V, 120

356 Clearances in reamer teeth II, 391
337 Clincher rims for gasoline car

43 wheels II, 222
23 Clutch accessibility I, 384
21 Clutch adjustment I, 384
23 Clutch bearings I, 383

307 Clutch facings II, 397
310 preparing leather II, 397

308 proper clutch leathers II, 397
310 putting leather on clutch II, 397

riveting process II, 397

67 Clutch group I, 17, 365

111 friction disc I, 415

75 individual clutch I, 409

345 miscellaneous types I, 416

318 planetary gears I, 413

173 sliding gear I, 395

44 transmission troubles and repair* I, 423
213 types of clutches I, 365

Note. — For page numbers see foot of pages.

402

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INDEX

Vol. Page

Clutch pedals

I, 381

Clutch spinning

I, 389

Clutch and transmission

V, 312

clutches

V, 312

transmission

V, 312

Clutch trouble and remedies

I, 384

cork inserts

I, 389

failure of clutch to take hold

I, 394

fierce clutch

I, 388

Ford clutch troubles

I, 388

handling clutch springs

I, 387

loss of power

I, 393

lubricating multiple-disc clutches I, 393

multiple-disc clutches failing

hold

I, 393

replacing clutch leathers

I, 385

slipping clutch

I, 384

spinning

I, 389

throwing in clutch

I, 393

troubles outside of clutch

I, 393

Clutches III, 310; IV, 364; V, 312

cone type V, 312

loss of power in I, 393

lubrication of I, 382

multiple-disc type V, 312

necessity for disengaging devicelll, 310
operation, methods of I, 380

requirements applying to all I, 365
roller type III, 312

Coefficient of expansion IV, 436

Coil spring absorber II, 117

combinations II, 118

double-coil-spring types II, 119

springs alone II, 117

Coils and vibrators III, 100

complication of multi-vibrator III, 101
function of the coil III, 100

master vibrator III, 101

necessity for vibrator III, 100

non-vibrator coil III, 102

Cold-riveting metals II, 398

Combinations for firing order III, 155
Combined radial and thrust bear-
ings I, 351
Commercial vehicles V, 265

classification

V, 267

Commercial vehicles (continued)
construction of frames II
electric vehicles V,
gasoline vehicles V,
Commercial-car wheels on gasoline
cars II
cast-steel wheels II
miscellaneous wheel types II
modern status of spring wheel II
requisites II.
wheel troubles and repairs II
wood wheels II
Commutator maintenance III
Commutators III
Complete renewal of battery V
burning groups V
dismantling the battery V,
initial charge V,
materials needed V,
reassembling the cells V,
recharge V,
test discharge V,
Condenser III
Conduction V,
Conductors III
Cone clutch I
Connecticut battery system III
Connecting rods * I
bearings I
design characteristics I
troubles and repairs I
Connecting welding apparatus IV
Constant-current generator III
Constant-potential generators III
Construction of motorcycles IV.
brakes IV,
clutches IV
drive IV
electrical equipment IV
gearsets, or change-speed mecha-
nisms IV,
lubrication IV
motors IV
regulation IV
spring and frame construction IV,
starting IV,

Vol. Page

Note. — For page numbers see foot of pages.

403

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INDEX

Vol. I
Construction and action of typical

. cell " y,

chemical action on charging

plate V,

discharge V,

efficiency of storage cell V,

electrolyte V,

forming the plate V,

general description V,

process of charging V,

restoring a sulphated battery V,
sulphating V,

Construction and efficiency of cell

plates V,

containers for the cell V,

life of the cell V,

measurement of capacity V,

rate of discharge V,

safe discharge point for plates V,

Contact makers or timers III,

Atwater-Kent interrupter III,

roller contact timer III,

Containers for cell V,

Contracting-band clutch I,

Control of starting and lighting

systems III, 301; IV

battery cut-out IV, 76,

controller V,

counter e.m.f. V,

electric brake V,

fuses V

methods of V

office of shunt V,

planetary gear IV,

Splitdorf system IV,

switch IV,

transmission IV,

Wagner system IV,

Westinghouse system IV,
Controller for electric vehicles V, 70,

care of V,

drum type V,

duplex control V,

flat radial type V,

flush type V,

Note.— For page number 8 see foot of pages.

'age

25
27
28
14
24
13
26
31
29

34
41
38
35
36
36
99
99
99
41
368

83
83
70
69
84
84
78
82
78
56
75
75
83
89
282
77
70
77
72
74

Vol. Page
Convection V, 202

Cooling systems for gasoline

motors I, 300; V, 305

adjusting fans

adjusting pumps

air cooling

circulating apparatus

cleaning

fans

radiator construction

replacements

washing

water cooling
Copper welding

after-treatment

general considerations

reparation

welding
Cork inserts in brakes
Counter-e.m.f.
Crankcases

arms and engine supports

construction

materials

modern tendencies in design

oil for

troubles and remedies ,
Crankshaft bearings
Crankshaft lapping
Curing excessive lubrication
Curing noisy tappet
Current and current control on
electric cars
battery equipment
brakes
controller
safety devices
tires
Cut-outs, muffler
Cutting blowpipe
Cutting gears in repair work
Cutting valve-key slots
Cyclemotor

Cycles of engine operation
Cylinder heads
Cylinder repairs

I, 316

I, 317

I, 314

V, 307

I, 316

V, 306

V, 305

I, 316

I, 300

IV, 472

IV, 474

IV, 472

IV, 473

IV, 473
I, 389

V, 69
I, 94
I, 97
I, 95
I, 97
I, 96
I, 343
I, 98
I, 85
I, 93
I, 70
I, 266

V, 282
V, 282
V, 287
V, 282
V, 285
V, 287

I, 300

IV, 478

II, 406

I, 272

IV, 334

.•I, 21

I, 49

I, 41

404

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INDEX

D
Dangers of overcharging
Dayton motorcycle
Defects in welds
Delco instructions
adjusting third brush

Vol. Page

V, 105
IV, 334
IV, 432
III, 402
III, 403
commutator maintenance III, 414

general instructions III, 402

seating brushes 111, 412

testing armatures III, 415

testing circuit breaker III, 411

testing cut-outs III, 408

testing field coils III, 420

tests of wiring III, 405

Delco starting and lighting

system III, 191, 381

earlier model interrupter III, 192

ignition relay III, 195

instructions III, 402

interrupter for higher-speed

engines III, 196

six-volt; single-unit; single-wire III, 381

six- volt; two-unit; single-wire III, 397

timer with resistance unit III, 193

Deposits of carbon in cylinder I, 45

Deppe gas generator I, 204

Development of steam engines V, 197

Dies in repair work II, 388

Differential lock V, 329

Dimming devices III, 325

Disc clutch I, 370

Discharge V, 27

Disco starting and lighting

system III, 425

Dismounting motor for repair II, 360
Distributor III, 103

Dixie magneto III, 122

Doble steam car V, 222, 249

lubrication V, 250

steaming test V, 250

Double brake drum for safety on

gasoline automobiles II, 178
Double spark ignition III, 134

Dragging brakes on gasoline cars II, 185
Drainage of public garages II, 334

Drill presses II, 418

function of II, 418

Note. — For page numbers see foot of pages.

Drill presses (continued)
lubrication in drilling
met hod of act ion
securing work

Drilling hard metals

Vol. Page

II, 420
II, 419
II, 420
II, 411

Drilling in modern repair shop II, 382

grinding drills II, 384

lubrication II, 385

sizes of drills II, 384

speed of drills II, 385

types of drills II, 382

Drive for motorcycles IV, 362

belt drive . IV, 362

chain drive IV, 363

shaft drive IV, 363

Drop forged axles II, 64

Dry bearings V, 153

Dual ignition system III, 128

Bosch type III, 128

details of typical distributor III, 131

Rerny type III, 130

typical wiring diagram III, 132

Duplex ignition system III, 133

Dynamotor connections IV, 48

Dynamotors III, 61, 381

Disco type III, 425

Dyneto type III, 425

North East type IV, 20

Simms-Huff type IV, 47

Splitdorf type IV, 55

Wagner type IV, 75

West inghouse type IV, 89

Early motorcycles IV, 327

Edison battery V, 48

advantages and disadvantages V, 50

composition of plate V, 48

size of battery V, 51

Edison cell not available IV, 200

Edwards carburetor I, 149

Effect of compression on indicator

card V, 214
Effect of high pressure and early

cut-off V, 215

Efficacy of storage cell V, 28

405

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INDEX

Electric automobiles
essential features of
similarity of types

Electric brakes

Electric circuit

Electric delivery wagon

Vol. Page
V, 11
V, 11
V, 12
II, 84; V, 84
III, 13
V, 269

current and current control V, 282

design of V, 270

general specifications V, 269

motive power V, 271

Electric drive I, 418; II, 55

Electric gearshaft IV, 182

Electric horns III, 319

Electric indicating instruments V, 163

ampere-hour meter V, 163

volt-ammeter V, 163

Electric motor principles III, 57

Electric starting and lighting

system III, 281; IV, 11

Electric tractors V, 287

Electric transmission I, 419; V, 335

advantages V, 335

several systems V, 336

Electric trucks

characteristics of chassis V, 291
classification V, 291
Electric vehicles V, 267
electric delivery wagon V, 269
electric trucks V, 291
special forms of V, 287
Electrical devices, inherent weak-
ness of III, 11
Electrical equipment IV, 367
automatic switches IV, 369
development from battery

current IV, 367
electric starting and lighting

systems HI, 281
elementary electrical principles III, 12
ignition III, 91
magneto generators IV, 369
Electrical pressure III, 14
Electrical principles III, 12
Electrical troubles IV, 398
care of brushes IV, 398
lubrication of electrical equip-
ment requires care IV, 398

Note. — For page numbers see foot of pages.

Vol. Page
Electrical troubles (continued)

short-circuits and open circuits IV, 39S
storage batteries IV, 39S

Electrically operated gears I, 407

Electrolyte V, 14, 104

adjusting specific gravity V, IS

determination of strength of acid V, 15
purity of acid and water V, 15

replacing evaporation or other

losses V, 17

temperature correction V, 15

Electromagnets • III, 32

Elementary dynamo III, 44

Elementary slide valve V, 212

Elevator vs. ramps for large size

garage II, 302

Elliott type of front axle II, 58

Emery paste for lapping work II, 381
Engine cylinders IV, 496

Engine group I, 13

carburetion sub-group I, 13

cooling system I, 15

cylinder and crankshaft sub-
group I, 13
exhaust system I, 15
flywheel I, 17
ignition system I, 15
inlet and exhaust valves I, 15
lighting system I, 17
lubrication system I, 16
starting system I, 16
Engine lubrication V, 256
Engine troubles I, 25
Engine types and details on

steam ears V, 221

Doble V, 222

National V, 226

Stanley V, 221

Evolution of motorcycle IV, 325

Exhaust-valve setting I, 263

Expanding band clutch I, 369

Expansion and contraction in

welding IV, 408, 436,

446, 453, 460, 468
External-contracting brakes II, 173

External lubrication I ; 332

406

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INDEX

Vol. Page

Four-wheel driving, steering, and

Fans

312

braking

Faulty ignition cause of trouble

III,

Four-wheel steering arrangement

Fellows gear shaper

438

Frames

11, 75,

487

Field magnets

III,

bracing methods

forms of

III,

classes of

permanent field used in mag-

effect on springs

neto

III,

general characteristics

self-excited fields

III,

presscd-steel

Fierce clutch

388

rigid

Filing methods in automobile

sub-frames

repair

II,

357

tendency in design

Final drive

317

troubles and repair

classification

318

types of

differential lock

329

Friction disc

415

double-reduction live axle

326

Frictional plate shock absorber

116

four-wheel drives

332

Front axles

front drives

330

bearings

internal gear-driven axle

326

materials

side-chain drive

318

troubles and repairs

worm drive

321

types

Fire-tube boilers

232

Front drives

330

fusible plug

233

early development

330

Stanley

232

electric front drive

330

Firing-up

254

Fuel feeding

223

Fisher Ford starter

IV,

142

Fuel supply

223

battery and wiring

IV,

145

Fuel system

1,230

240

mounting starting unit

IV,

143

Fuels and burners for steam cars

226

operating instructions

IV,

147

burner principles

227

preparing engine

IV,

142

gasoline and kerosene as fuels

226

Finish filings

11,

395.

pilot light

228

Firing orders

III,

153

types of burners

228

Fitting piston rings II,

373

,376

Fuels and oils for public

garages

336

Fitting taper pins

II,

393

Full elliptic springs

Flash boilers

237

Full floating axle

154

Floats

115

Fuses III,

317, 339

Flooding of carburetor

217

Fusible plug

256

Flux for welding IV,

109

, 461

Flywheel characteristics

351

Flywheel markings

260

Ford clutch troubles

388

Garage furniture

339

Ford magneto

III,

134

Garage tools

345

Ford planetary type

414

Gases

403

Ford steering gear

11,

Gasoline automobiles

Foreign kerosene carburetors

193

chassis group

Forming battery plate

final-drive group

137

Four-wheel drives

332

steering gears

Note. — For page numbers see foot of pages.

407

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INDEX

Vol. Page

Gasoline delivery wagons

295

Autocar

295

classification limits

295

White

299

Gasoline-driven traction engines

343

mechanical details

343

types

347

Gasoline pump

261

Gasoline strainer a source of trouble I,

207

Gasoline trucks

300

details of chassis and running

gear

338

motor details

301

power transmission details

312

Gasoline vehicles

295

gasoline delivery wagons

295

gasoline-driven traction engines V,

343

gasoline trucks

300

trailers

341

Gasoline and kerosene as fuels

226

Gassing of battery electrolyte

iv,

209

Gear cases

Gear drive

Gear pitch and faces

447

Gear pullers

425

Gear troubles

447

Gears

435

Gearsets

IV,

365

Generator principles

III,

Generator-starting motor

iv,

Generator tests

III,

354

Generators III, 347, 355, 372,

397, 426, 430, 44fl

i, IV 405

Gleason gear planer

439

Gradual clutch release

381

Gravity feeding

331

Gray & Davis starting and light-

ing systems

iv,

114

adjusting cut-out

111,

447

adjusting regulator

111,

449

generator test chart

III,

442

installation of Ford starter

iv,

114

instructions for operating Ford

starter

iv,

125

six-volt; two-unit; single-wire

system

111,

430

starting-motor test chart

III,

446

Vol. Page
Gray & Davis starting and light-
ing systems (continued)
testing generator with am-
meter on Ford

starter IV, 127

Grease cups I, 344

Grinders II, 415

Grinding drills in repair shop I, 384

Grinding-out cylinder bore I, 51

Grinding valves I, 272

" H. & N " duplex carburetor I, 201
adjustments I, 203
installation precautions I, 202
starting I, 203
Hand keyseating II, 394
finish filings II, 395
keyseating process II, 3&4
Woodruff keys II, 396
Hand tools for public garages II, 344
Handling clutch springs I, 387
Handling crankshaft in machines I, 91
Handling expansion and contrac-
tion in welding IV, 439
heating confining members IV, 438
heating entire casting IV, 438
use of wedges IV, 438
Handy spring tool I, 431
Handy test set for electric circuit III, 340
Hart-Parr tractor V, 349
Headlight glare III, 324
Heat treatment in automobile

repair II, 403

bonding rods II, 406

hardening high-speed steel II, 405

hardening steel II, 404

self-hardening steel II, 405

tempering steel II, 403

Heating transformation V, 206

Heat transmission V, 201

conduction V, 202

convection V, 202

expansion V, 202

radiation and absorption V, 202

relative conductivity V, 202

temperature scales V, 203

Note. — For page numbers sec foot of pages.

408

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INDEX

Vol.

Heat value of fuels V,

Heat and work V,

heat transformation V,

heat transmission V

laws of gases V,

thermodynamics of steam V

Heating effect of current III

Heating for public garages II

Heavy sheet-steel welding IV

Heavy welding section IV,

Heinze-Springfield starting and

lighting system III

Heinze-Springfield Ford starter IV

Helical and herringbone gears I

High-tension ignition system III

High-tension magneto III

Hoists and cranes for repair work I

Holley carburetors I, 134, 137

Holt caterpillar tractor V,

Hot-riveting metals II,

Hotchkiss drive II
Hydraulic analogy for ignition

system III,

Hydraulic brakes for gasoline cars 1 1

Hydraulic transmission I

Janney-Williams I

Manly I

Hydrometer IV,

frozen cells IV,

low cells IV,

tests IV,

variations in readings IV

Ignition III, 91, 179

fundamental ignition principles III, 91

ignition, motorcycle IV, 383

ignition setting point III, 151
ignition system, fixed timing

point III, 148

ignition systems III, 128

ignition systems on motor trucks V, 304
ignition trouble eliminated by

efficient devices III, 202

modern battery ignition system III, 179

sources of current III, 90

spark timing III, 139

Note. — For page numbers see foot of pages.

Page Vol. Page

206 Ignition (continued)
201 standard types

206 testing, adjustment and main-

201 tenance

204 Improper inflation of tires
208 Improved forms of battery types

28 Edison battery

333 ironclad Exide type

451 nature of improvements

458 starting batteries

Incandescent lamps
449 Bosch type

127 Mazda type

443 tungsten and other filaments

94 Indicator diagrams
115 Individual clutch

28 Induction
, 192 Inductor-type magneto
354 Industrial trucks
398 Inherently controlled generator
102 Inlet manifold

design and construction
109 troubles

182 Inner tire tube repairs
417 Inside tire casing forms
417 Installation of Gray & Davis Ford
417 starter

201 battery

205 final connections and adjust-

206 ments

203 mounting starter-generator

204 preparing engine
priming device
remounting engine parts
starting switch

Installing battery IV,

Installing special system for Ford

cars

Fisher

Gencmotor

Gray & Davis

Heinze-Springfield

North p;ast

Splitdorf

Westinghouse
Interchangeable Continental tires II,
Interchangeable Michclin tires II,

III, 128

III

i
i

ii
n

IV
IV

IV
IV
IV
137

IV
IV
IV
IV
IV
IV
IV
IV

409

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INDEX

Vol. Page
Interlocking devices I, 405

Internal cooling and scavenging I, 315
Internal-expanding brakes II, 174

Internal-gear drive II, 153

Internal gear-driven axle V, 326

International tractor V, 347

Ironclad Exide battery V, 43

improved connectors V, 45

negative plate V, 44

positive plate V, 43

separators V, 44

Instructions
Apperson starter equipment III, 368
Dyneto starter III, 426, 429

for connecting welding appara-
tus IV, 422
Gray & Davis Ford starter

III, 439; IV, 125
Heinze-Springfield system III, 452

Hupp starter equipment III, 367

Jeffery (Chesterfield six) equip-
ment III, 366
Leece-Neville system IV, 11
North East system IV, 24
Packard starter equipment III, 370
Remy system IV, 42
Scripps-Booth starter equip-
ment III, 369
Simms-Huff system IV, 52
Splitdorf system IV, 161
U. S. L. system . IV, 64
Wagner system IV, 85
Westinghousc system IV, 89
Winton starter equipment III, 363

Jacking-up troubles

162

Jeffery-Bijur starter

in,

337

Jeffery "Quad"

334

Johnson carburetor

179

Johnson tractor

352

Joint hydrometer and voltmeter

tests IV, 218, 255

K
Keyseating process
Kingston carburetors

II, 394
I, 139

Vol. Pago
Kingston carburetors (continued)

dual form , I, 140

enclosed type I, 139

model L I, 141

Knight sleeve valves I, 286

Knocking in engine I, 25

Lamp voltage

HI,

322

Lapping engine cylinders

II,

379

cleaning after grinding

II,

382

cleating down castings

II,

380

emery paste

II,

381

lapping by drill press

II,

381

lapping by hand

II,

379

proper fit for piston

II,

380

worn cylinders

II,

379

Large size garage

II,

302

Latent heat

208

Lathe equipment

II,

423

Lathe work

II,

424

Lathes

II,

421

Laws of gases

2(H

behavior with changes of tem-
perature V, 205
Boyle's law V, 2M

Laws of magnetic attraction and

repulsion III, 31

Lead burning V, 139

first method of burning V, 139

hydrogen-gas outfit V, 143

illuminating gas outfit V, 142

second method of burning V, 140

type of outfit V, 139

use of forms to cover joint V, 140

Leece-Neville starting and lighting

system IV, 11

Lemoine type of front axle II, 60

Lighting III, 321

dimming devices III, 325

headlight glare III, 324

incandescent lamps III, 321

lamp voltage III, 322

lighting batteries III, 322

lighting of public garage II, 330

reflectors III, 323

Note. — For page numbers see foot of pages.

410

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INDEX

Vol. Page

Lines of magnetic force III, 35

Longuemare carburetor I, 151

adjustments I, 153

changing choke tubes I, 155

operation I, 152

Loosening seized pistons I, 65

Lost motion and backlash II, 35

Low-tension magneto III, 113

Lubrication IV, 359, 384; V, 307

drilling II, 395, 420

multiple disc clutches I, 393

oil pumps IV, 359

path of oil IV, 359

steering-gear assembly II, 46

transmission gears I, 434

Lubrication troubles and remedies I, 339

bending oil pipes I, 343

care of lubricant in cold weather I, 339

mammoth grease gun I, 339

oil filtering outfit I, 342

oil settling tanks I, 342

oil tank and outfit for testing

bearings I, 340

Machine tools for public garages II, 345

drill press II, 346

emery wheel or grinder II, 346

grinding in lathe II, 348

hack saw II, 346

lathe II, 345

lathe accessories II, 345

milling in lathe II, 348

utility of portable electric motor II, 349

Machines and machine processes II, 411

Machining crankcases I, 99

Magnetic clutch I, 378

Magnetic field III, 33

Magnetism III, 30

electromagnets III, 32

laws of magnetic attraction

and repulsion III, 31

lines of magnetic force III, 35

magnetic field III, 33

magnetic substances III, 32

natural and artificial magnets III, 30

Note. — For page numbers see foot of pages.

Vol. Page
Magnetism (continued)

poles of a magnet III, 31

solenoids III, 35

Magneto, working principle of III, 112

Magneto mounting III, 177

Magneto speeds III, 147
Major equipment for public garage II, 330

Malleable iron IV, 467

Malleable-iron welding IV, 467
Management and care of steam

cars V, 252

adjusting throttle V, 262

care of burner V, 261

care of engine bearings V, 260

causes of low pressure V, 256

end of run V, 255

engine lubrication V, 256

filling boiler V, 257

firing-up V, 254

fusible plug V, 256

gasoline pump V, 261

general lubrication V, 258

management on road V, 252

operating instructions V, 262

operating cut-off and reverse V, 261

raising gasoline pressure V, 258
scale prevention and remedies V, 257

water pump V, 259

Mandrel for turning pins I, 67

Manifolds, engine IV, 494
Manipulation of blowpipe and

welding-rod IV, 427

Marmon self-lubricating axle II, 61

Marvel carburetor I, 169

adjustments I, 171

fuel supply I, 172

Master carburetor I, 148

Materials for front axles II, 63

cast axles II, 63

change of axle type simplifies II, 66

drop forgings II, 64

forgings H» 64

prcssed-steel axles II, 65

tubular axles II, 65

Measuring acetylene consumptionlV, 502

Measuring oxygen consumption IV, 499

411

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INDEX

Vol. Page
Mechanical connection of Remy

starter IV, 40

National IV, 42

Oakland IV, 42

Reo IV, 42

wiring diagrams IV, 40
Mechanical elements of steam

engine V, 211
slide valve V, 212
superheated steam and com-
pound expansion V, 216
valve gears V, 219
Mechanical equivalent of heat V, 207
Medium size garage II, 296
typical arrangements II, 296
Melting point of substances IV, 434
Merkel motorcycle IV, 334
Methods of arranging cars in

public garage II, 286
Methods of boosting in battery

charging V, 111
approximate constant-poten-
tial method V, 111
constant-current method V, 112
constant-potential method V, 111
Method of battery charging V, 93
automatic charge-stopping de-
vice V, 99
charging an Edison battery V, 107
charging rate V, 96
dangers of overcharging V, 105
electrolyte V, 104
making proper connections V, 93
precautions V, 98
starting charge V, 98
temperature of battery V, 95
testing progress of charge V, 101
time required to charge V, 106
voltage after charging V, 94
Methods of casting cylinders I, 34
cast in pairs I, 35
cast separately I, 34
cast together I, 35
Methods of control of electrics V, 78
resistance in circuit V, 80
series and multiple connections V, 78
wiring diagram V, 81

Note. — For page numbers see foot of pages.

Vol. Pagp

Methods of cylinder lapping I, 51

Methods of fastening flywheels I, 353

Methods of pre-heating in welding IV, 441
charcoal fire IV, 443

gas and oil burners IV, 442

pre-heating with welding blow-
pipe IV, 441

Methods of regulation of electric
starting and light-
ing systems III, 287
constant-potential generators III, 292
independent controllers III, 291
inherently controlled generator III, 289
necessity for control of genera-
tor output III, 287

Methods of storage of batteries V, 137
dry storage V, 138

wet storage V, 137

Milling machines II, 431

cutters II, 431

types II, 431

Modern battery ignition systems III, 179
effect of starting and lighting
developments on
ignition III, 179

generator design follows mag-
neto precedent III, 179
typical arrangement III, 181

Motor design for tractors V, 344

multi-cylinder motors V, 346

Rumely kerosene motor V, 344

Motor governors for trucks V, 30S

centrifugal type V, 309

controlling car speed V, 309

general characteristics of V, 309

hydraulic type V, 310

Motor lubrication I, 319

external lubrication I, 332

gravity feeding I, 331

individual pump pressure feeding I, 331
interior and exterior demands I, 319
single-pump pressure feeding I, 322
splash lubrication I, 332

splash-pressure feeding I, 320

Motor windings and poles III, 303

commercial forms III, 304

standard design III, 303

412

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INDEX

Vol.

Page

Motor-car construction

clutch group

engine group

final drive group

frame group

steering group

transmission group

Motorcycles

325

analysis of motorcycle

mechanisms

343

construction details

349

control

385

evolution of

IV,

325

history

IV,

327

light-weight types

IV,

336

mechanism nomenclature

343

operation and repair of motor-

cycles

IV,

381

overhauling

388

present trend of models

IV,

327

principles of engine operation

IV,

345

special bodies and attachments IV,

376

standard specification

IV,

325

types of motorcycles

IV,

330

Motors, electric

armature

capacity for overloads

essentials of motor

motor speeds

parts of motor

principle of rotation

Motors, motorcycle

351

four-cylinder type

356

single-cylinder type

351

two-cylinder type

353

N
National steam car

225

Natural and artificial magnets

III

Necessary equipment for public

garage

330

air-supply system

338

drainage

334

fuels and oils

336

garage furniture

339

garage tools

344

heating

333

Vol. Page

Necessary equipment for public
garage (continued)

lighting

major equipment

provision for moving cars

provision for power

special stands for units

ventilation

water supply

work benches
Needle valves

external needle type

external sectional needle type

internal needle type

simple vertical tube
Neglect of lubrication
New developments in carburetors

effect of heavier fuels

effect of motor changes

effect of vacuum feeds
Newcomb carburetor

adjustments

dashpot

mixture indicating pointer

starting device
Noise in gear operation
Noisy bevel gears

lining up axles

Packard bevel adjustment

repair for broken spring clips

taking out bend in axle
Noisy valves
Non-alignment of axles
Non-alignment of steering wheels
Non-conductors of electricity
Non-leaking piston rings
North East Ford starter

mounting battery

mounting starter

operating instructions

preparing engine
North East starting and light-
ing system

dynamotor

instructions

protective devices

switch tests

II,

330

II,

330

II,

335

II,

335

II,

343

II,

333

II,

333

II,

341

114

115

114

344

120

121

166

169

167

168

167

423

II,

167

II,

169

II,

167

II,

168

II,

169

274

152

151

III,

IV,

147

IV,

151

IV,

148

IV,

152

IV,

147

IV,

Note. — For page numbers see foot of pages.

413

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INDEX

Vol. Page
North East starting and light-
ing system (continued)
twelve- volt; sixteen- volt, or
twenty-four - volt;
single-unit; single-
wire, or two wire IV, 20
wiring diagrams IV, 22

Notes on cutting

cutting dirty and poor material IV, 481
cutting round shafts, etc. IV, 481

heating flames IV, 481

piercing holes IV, 481

restarting cut IV, 481

speed of cutting IV, 481

Obstruction in carburetor needle

valve
Ofeldt boiler system

automatic fuel feed

fuel, water and steam connec-
tion
Ohm's law
Oil filtering outfit
Oil settling tanks
Oil tank and outfit for testing
Oils and greases

characteristics of good oils

principles of effective lubrica-
tion

testing oils for acid, etc.
Oily motorcycle clutches
Operating cut-off and reverse on

steam cars
Operating instructions

Gray & Davis Ford starter

North East Ford starter

Westinghouse Ford starter
Operating suggestions for motor-
cycles

carburetor

control

ignition

lubrication

motor

tires

valves

Note. — For page numbers see foot of pages.

217

251

252

251

III,

342

340

336

337

IV,

395

261

IV,

113

iv,

152

iv,

176

iv,

381

IV,

383

iv,

385

iv,

383

iv,

384

iv,

381

IV,

3S5

iv,

3S2

IV,

416

IV,

430

IV,

421

iv,

422

iv,

416

iv,

416

iv,

419

iv,

416

IV, 3S1

Vol. Page
Operation and care of welding
apparatus

general notes on welding

hose

instructions for connecting ap-
paratus

necessary apparatus

necessity for care

regulators

welding blowpipe
Operation and repair of motor-
cycles
Operation principles of electric
motors

rotation, how produced
Outer shoe, or casing, repairs

blowouts

classifying troubles

retreading

rim-cut repair

sand blisters

use of reliner
Overhauling and repair of motor-
cycles

air leaks in inlet manifold

carburetors

cleaning chains

dirty muffler

electrical troubles

oily clutches

overhauling

valve timing

valve troubles
Overhead and vertical welding

beginning long weld
Overload springs
Oxidation in welding process
Oxy-acetylene cutting
Oxy-acctylene flame IV, 408, 424

carbonizing, or reducing flame IV, 426

caution .against oxidizing flame IV, 426

flame regulation IV, 425

neutral, or welding flame IV, 425

oxidizing flame IV, 420

removing carbon IV, 485

use of reducing flame IV, 420

in,

ii,

260

ii,

261

ii,

260

ii,

26i

ii,

263

ii,

261

ii,

266

IV,

388

iv,

390

iv,

38S

IV,

396

IV,

397

iv,

398

iv,

395

IV,

390

iv,

393

IV,

389

iv,

431

iv,

431

II,

124

iv,

468

iv,

410

414

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INDEX

Vol. Page

Oxy-acetylene process IV, 403, 424

advantages of IV, 403

character of flame IV, 424

expansion and contraction IV, 408

flux IV, 409

gases IV, 403

generators IV, 405

oxy-acetylene cutting IV, 410

oxy-acetylene flame IV, 408

preparation of work IV, 408

strength of weld IV, 409

welding blowpipes IV, 407
Oxygenerator vaporizing device I, 189

adjustments 1, 192

Packard carburetor I,

adjustments I,

Packing a battery
Parker pressed-steel wheels
Parts of storage cell

electrolyte

elements

separators
Parts of electric motor
Passenger attachments for motor-
cycles

novelties in motorcycle equip-
ment
Peening

Perlman tire rim patents
Piston and ring troubles and repairs I

bushing removers

curing excessive lubrication

loosening seized pistons

mounting pistons on lathes

non-leaking rings

removal and replacement of
pistons

testing size of new piston

tracing a ring knock
Piston construction
Piston pins
Pistons and accessories

characteristics of piston rings

piston construction

piston pins

185
186
146
203
193
193
193
193
56

376

378
410
236
63
66
70
65
71
69

63
69
70

58
62
58
59
58
62

216

220

Vol. Page
Pistons and accessories (continued)

types of piston rings I, 61

Platform springs H, 99

Pleasure-car wheels II, 192

Parker pressed-steel wheels II, 203

sheet-steel wheels II, 200

wire wheels H> 196

wood wheels H, 192

Planetary gears I, 413

Ford planetary type I, 414

Pneumatic drive I, 418

Pneumatic gear-shift 1, 409

Pneumatic tires II, 213

changing tires II, 218

classification II, 213

proper tire inflation pressures II,

recent tire improvements II,

Poles of a magnet III,

Popping in carburetor I,

Position of blowpipe in welding IV, 427

importance of movement IV, 429

inclination of blowpipe IV, 427

movement of blowpipe IV, 428

travel of blowpipe IV, 428

Position of hose in welding IV, 427

Position of welding rod IV, 429

building-up weld IV, 430

faults to be avoided IV, 430

when to add welding rod IV, 429

Position of work in soldering II, 372

Pouring babbitt in bearings II, 365

Power hack saws II, 420

allowance for cut II, 421

method of action II, 420

pressure for different metals II, 421

pressure on blades II, 420

Power transmission details in

trucks V, 312

clutch and transmission V, 312

electric transmission V, 335

final drive V, 317

Practical analysis of types III, 327

Auto-Lite system III, 346

Bijur system III, 355

Bosch-Rushmore system III, 372

Delco system III, 381

Disco system III, 425

Note. — For page numbers see foot of pages.

415

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INDEX

Vol. Page
Practical analysis of types (con-
tinued)
Dyneto system HI, 425

Gray & Davis system III, 430

Heinze-Springfield system III, 449

Leece-Neville system IV, 11

North East system IV, 20

Remy system IV, 35

Simms-Huff system IV, 47

Splitdorf system IV, 55

U. S. L. system IV, 61

use of protective and testing

devices III, 337

Wagner system IV, 75

Westinghouse system IV, 89

Pre-heating air for carburetors I, 214

Pre-heating in cast-iron welding IV, 460

Preparing engine for Ford starter

Fisher IV, 142

North East IV, 147

Splitdorf IV, 154

Westinghouse IV, 162

Preparation of cast-iron welds IV, 462
to prevent crack from extending IV, 462
Pressed-steel axles II, 65

Pressed-steel frames II, 78, 81

Pressing gears on shafts I, 425

Pressure and voltage III, 40

fall in pressure III, 40

Primary batteries III, 96

defects of dry cells III, 96

liquid batteries III, 97

Principle of compensating support V, 339
Principle of cutting with oxygen IV, 477
metals that can be cut IV, 477

Principles and construction of
starting and light-
ing storage battery IV, 192
action of cell on charge IV, 195

action of cell on discharge IV, 196

capacity of battery IV, 197

construction details IV, 199

Edison cell not available IV, 200

function of storage battery IV, 192
parts of cell IV, 193

specific gravity IV, 195

Note. — For page numbers Bee foot of page*.

Vol. Page
Principles of engine operation IV, 345
classification IV, 345

four-cycle type IV, 345

two-cycle type IV, 347

Process of charging storage bat-
teries V, 26
charging rate and time of charge V, 26
gassing V, 27
precautions regarding electrolyte V, 26
Progressive type of sliding gear I, 395
Proper tire inflation pressures,

gasoline cars II, 216

standard pressure and oversize

tires II, 217

Properties of metals IV, 434

coefficient of expansion IV, 436

expansion and contraction IV, 436

handling complex case of ex-
pansion and con-
traction IV, 439
handling simple case of expan-
sion and contrac-
tion IV, 437
melting point IV, 434
specific heat IV, 436
Protective devices III, 296, 387; IV, 20
automatic battery cut-out HI, 296
battery cut-out HI, 387
circuit-breaker III, 388, 398
various forms III, 296
Provision for moving cars in

public garages II, 335

Provision for power in public

garages II, 335

Public garages
designs of public garages II, 291

finances and building costs II, 316

necessary equipment for garage II, 330
preliminary problems II, 281

typical exterior design II, 321

Push rods and guides I, 280

Putting new battery in commis-
sion V, 145
charging V, 146
inspection of battery V, 145
replacements V, 146

416

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INDEX

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Putting the battery out of com-
mission V, 137
methods of storage V, 137

Q. D. type for straight sides II, 228
Quick-detachable rims for gasoline

car wheels II, 222

quick-detachable No. 2 II, 225

Quick-detachable clincher forms II, 227

R
Radiation and absorption V, 202
Radiators and piping I, 303
modification of cellular and tubu-
lar forms I, 306
types of cells I, 305
types of tubes 1, 305
Railway car needs I, 409
Range of business in public garages II, 281
financial problems II, 283
selling accessories II, 282
selling cars as side line II, 282
service of public garage II, 281
special side lines II, 283
Range of use of electric vehicles V, 267
Rate of discharge of storage cells V, 36
Rayfield carburetor 1, 159
adjustments I, 160
Reading micrometer II, 379
Reamers II, 392
fluted chucking II, 392
spiral-fluted II, 392
three-flute chucking II, 392
Reaming in shop II, 389
characteristics of hand reamers II, 392
clearances II, 391
function of reamer II, 389
kinds of reamers II, 392
number of teeth II, 390
Rear axles II, 137, 165
assembling II, 167
disassembling rear construction II, 166
rear-axle troubles and repairs II, 162
transmission II, 137
truss rods II, 165
types of rear axles II,_149

Note. — For page numbers see foot of pages.

Vol. Page

Rear-axle housings II, 157

Rear-axle lubrication II, 162

Rear-axle troubles and repairs II, 162

checking up Ford axles II, 171

jacking-up troubles II, 162

locating trouble II, 170

noisy bevel gears II, 167

rear-axle II, 165

universal-joint housings II, 164

workstand equipment II, 163

Rear-end changes in frames II, 87

Rear-wheel bearings II, 161

Reassembling calls V, 130

Rebabbitting bearings II, 364

finishing bearing II, 366

pouring the babbitt II, 365

types of jig use II, 364

Recharging batteries V, 135

Reflectors III, 323

comparison of parabolic with lens

type III, 323
parabolic type III, 323
types for various locations III, 323
Regulation of electric generator III, 346
North East system IV, 20
Remy system IV, 35
Simms-Huff system IV, 47
Splitdorf system IV, 56
U. S. L. system IV, 62
Wagner system IV, 83
Westinghouse system IV, 89, 91
Regulation in construction of motor-
cycles IV, 371
Regulation of starters III, 355, 398, 372
ballast coil employed III, 372
Delco system III, 384
Disco system III, 425
Dyne to system III, 426
Gray & Davis system III, 431
Heinze-Springfield system III, 450
Regulators in welding IV, 419, 479
acetylene regulator IV, 420
care of regulators IV, 420
operation of regulator IV, 419
oxygen welding regulator IV, 420
Regulator cut-out III, 434
to check candle power of lamps III, 434

417

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INDEX

Vol. Page

Regulator cut-out (continued)

to check cutting-out point III, 435

to check for adjustment III, 434

to check for closing voltage III, 434

Relation of tires to mileage V, 156

Relative conductivity • V, 202

Removal and replacement of piston I, 63

Removal of carbon 1, 41

Removing steering gear II, 34

Removing valve I, 266

Removing valve spring I, 267

Remy system III, 188; IV, 40

detecting grounds III, 189

igniting switch III, 190

instructions IV, 42

interrupter and distributor III, 190

mechanical combination IV, 40

Repairing cracked water jackets I, 53

Repairing poppet valves and

valve parts I, 266

Repairs, engine I, 26

general instructions I, 26

hoists and cranes I, 28

Replacing clutch leathers I, 385

Replacing defective battery jar V, 123

Replacing pistons in cylinders I, 56

Reserve tanks I, 229

Resistance III, 15

Restoring a sulphated battery V, 31

sulphate tests V, 31

treatment for sulphating V, 31

Retreading tires II, 264

building up tread II, 265

repairing carcass II, 264

Rims for gasoline car wheels II, 222

clincher rims II, 222

demountable rims II, 228

kinds of rims II, 222

Perlman rim patents II, 236

plain rims II, 222

quick-detachable tire rims II, 222

standard sizes of tires and rims II, 237

Riveting II, 396

brake linings II, 396

clutch facings II, 397

cold-riveting metals II, 398

hot-riveting metals II, 398

Note. — For page numbers see foot of pages.

Vol. Page

Riveting (continued)

installing new ring gear

II,

399

Riveting frame

II,

Roller bearings

1,346,

II,

Rumely tractor

347

Safe discharge point for plates V, 36

Safety devices V, 285

charging circuit-breaker V, 286

circuit-breaker and hand switch V, 285

cut-out switch connected to

brake V, 285
devices to prevent accidental

starting or tamperingV, 286
Sagging of frames II, 91
Samson tractor V, 351
Sand blisters in tire repairs II, 261
Scale prevention and remedies V, 257
Schebier carburetors I, 172
adjustment of model "L" I, 172
adjustment of model "R" I, 174
adjustment of model "S" I, 174
adjustment of model "T" hori-
zontal I, 175
Seating brushes, Delco III, 412
Self-induction • III, 38
Selling accessories for public

garage II, 282
Selling cars as side line in public

garages II, 282

Semi-elliptic springs II, 97

Semi-reversible gear II, 33

Senrab carburetor I, 195
Separate casing moulds for patch

work II, 249

Service of public garage II, 281
Shackles and spring horns for

springs II, 110

Shaft-driven Genemotor IV, 105

ammeter IV, 114

adjustment of gears IV, 108

failure to start IV, 114

mounting Genemotor IV, 108

operating instructions IV, 113

preliminary adjustments IV, 105

Shaft and axle IV, 493

418

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INDEX

Vol. Page
Shaft and chain transmission V, 276
Shapers II, 428
characteristics II, 428
clamping work in shaper II, 428
operation suggestions II, 430
Sheet-steel wheels II, 200
Shock absorbers II, 115
coil springs, alone and in com-
bination II, 117
frictional plate type II, 116
function II, 115
general classes of absorbers II, 115
overload springs II, 124

Shop information for garages II, 353

bench work II, 353

importance of equipment II, 353
machines and machine processesll, 411

Side chain drive for trucks V, 318

radius and torque rods V, 320

speed reduction V, 321

standard types V, 319

Simple welding job IV, 414

apparatus required IV, 414

connecting apparatus IV, 414

preparing the metal IV, 414

Single-cylinder motor IV, 395

Single-pump pressure feeding I, 322

Marmon I, 326

methods of driving pumps I, 327

Stearns I, 324

types of oil pumps I, 326

Single-wire and two-wire start-
ing systems III, 283

Six-volt; two-unit, Disco III, 425

instructions III, 425

units HI, 425

Six-volt; two-unit Dyneto III, 426

instructions III, 429

generator III, 426

starting motor III, 428

wiring diagram III, 428

Six-volt; two-unit; single-wire

systems III, 346,397,430,449

battery cut-out III, 350

battery cut-out tests III, 355

generator III, 346, 397

Gray & Davis III, 430

Note. — For page numbers eee foot of page*.

Vol. Page
Six-volt; two-unit; single-wire
systems (continued)
Heinze-Springfield III, 449

instructions III, 351

instruments III, 351

regulation III, 347, 398

starting motor III, 348, 398

starting switch III, 399

wiring diagram III, 351, 399

Size of conductors III, 26

Sizes of drills in automobile repair II, 384
Sliding gear I, 395

Slide valves V, 212

effect of adding steam lap V, 215

effect of compression on indica-
tor card V, 214
effect of high pressure and early

cut-off V, 215

elementary slide valve V, 212

indicator diagrams V, 214

use of steam cut-off V, 213

•Slipping clutch I, 384

Small tool equipment for tire repair

shop II, 255

Small size public garage II, 291

Smith motor wheel IV, 330

Soldering II, 371

general instructions II, 371

heavy work II, 372

light work II, 372

position for work II, 372

soldering flux II, 371

special stoves and irons II, 373

use of blow torch II, 372

Soldering flux II, 371

Solenoids IN, 35

Solving ignition troubles III, 204

breakdown of magneto 111,206

care of Ford magneto IN, 210

effect of compression on spark 111,205

inspection of contact breaker III, 204

leakage at distributor IN, 205

magnet recharger III, 208

remagnetizing HI, 207

sparking at safety gap 111,206

Sources of current IN, 96

419

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INDEX

Vol.

Page

Sources of current (continued)

alternating current

charging current

chemical sources of current

III,

direct current

induction sources of ignition cur-

rent

III,

112

voltage and spark control de

vices

III,

Sources of power loss

151

armature troubles

155

brushes and commutator

154

dry bearings

153

non-alignment of axles

152

non-alignment of steering

wheels

151

worn chains and sprockets

152

Spark plugs

III,

104

electrode arrangement

III,

106

fundamental requisite

III,

105

magnetic plugs

III,

107

plug threads

III,

108

priming plugs

III,

108

series plugs

III,

107

waterproof plugs

III,

108

Spark timing

III,

139

advance and retard

III,

139

automatically timed systems

III,

148

effect of irregular sparking

III,

139

firing order

III,

153

ignition setting point

III,

151

magneto speeds

III,

147

Special side lines in public garage

283

Special types of drive

electric drive

II,

four-wheel driving, steering and

braking

four-wheel steering arrangement 11

front wheel drive

Specific gravity

iv,

195

Specific heat IV, 436; V

,206

Speeding up old engines by lighten-

ing pistons, etc.

Spiral bevels

445

Spiral gears

444

Splash lubrication

332

Splash-pressure feeding

320

Vol. Page
Splitdorf Ford starter IV, 154

Splitdorf starting and lighting sys-
tem IV, 55
Spring and frame construction of

motorcycles IV, 349

Springs II, 96; IV, 492; V, 338

basis of classification II, 96

construction and materials II, 112

lubrication II, 111

principle of compensating sup-
port V, 339
semi-elliptic type V, 338
spring troubles II, 112
Spot-welder IV, 411
Spur gears I, 442
Standard sizes of tires and rims II, 237
Standard threads in tapping II, 385
Standard types of ignition sys-
tems III, 128
double-spark ignition III, 134
dual ignition system III, 118
duplex ignition system III, 133
Ford magneto III, 134
Stanley fuel, water and steam sys-
tems V, 241
Stanley steamer V, 221
Starting and lighting storage

batteries IV, 191

Starting motor III, 299, 348,

357, 372, 398, 428
Gray & Davis III, 431

Heinze-Springfield III, 450

Leece-Neville IV, 12

method of operation III, 372

motor windings and poles III, 103

Remy IV, 39

Simms-Huff IV, 51

Splitdorf IV, 59

starting switch III, 373

voltage III, 303

Wagner IV, 83

Westinghouse IV, 96

Starting switch III, 399

Steam automobiles V, 197

boilers V, 200, 232

boiler accessories and regulation V, 240
characteristic features V, 198

Note. — For page numbers see foot of pages.

420

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INDEX

Vol. Page

Steam automobiles (continued)
engine types and details
fuels and burners
management and care of steam

cars
simplicity of control
Steel welding

general considerations
heavy sheet-steel welding
light sheet-steel welding
welding heavy steel forgings
and steel castings
Steering gears

action of wheels in turning
Ford steering gear
general characteristics of steer-
ing gears
general requirements
inclining axle pivots
removing steering gear
steering-gear assembly troubles

and repairs
steering levers in front of axle
worm-gear types
Steering-gear assembly troubles
and repairs
lost motion and backlash
Steering rod, or drag link
Steering wheels
Stewart carburetor
Storage battery

construction and action of

typical cell
construction and efficiency of

cell plates
purity of acid and water
types of cells
Stoves and soldering irons
Straightening axle
Strength of weld
Stretching brake lining
Stromberg carburetors
general instructions
preliminary adjustments
starting adjustments
Sub-frames

V, 221
V, 226

V, 252
V, 201
IV, 443
IV, 443
IV, 451
IV, 446

IV, 457

II, 11

IV,
II,

II,
II,
II,
II,

II,
II,
II,

II,
II,
II,
II,
I,
V.

16
11
12
34

35
14
21

35
35
40
36
176
12

V, 13

II,

IV,

II,

I,
II,

Vol. Page

V, 29,

115

150

210

216

III,

313

Sulphating

preventing sulphating

Sunderman safety carburetor

Superheating

Superheated steam and com-
pound expansion

Switches

electrically operated switches III, 316
miscellaneous starting switches III, 315
Westinghouse starting switch III, 314

Switch and wiring IV, 133

battery cables IV, 136

charging wire and starting

cable IV, 136

coil and magneto wiring IV, 136

wiring for lights IV, 136

Switch tests IV, 31

373

409

188

122

123

Tables of valve settings

248

Tank placing

223

Tapping in repair shop work

ii,

385

dies

ii,

388

standard threads

ii,

385

tapping process

ii,

388

taps

ii,

386

Technique of gas welding

IV,

414

operation and care of welding

apparatus

IV,

416

simple welding job

IV,

414

welding different metals

IV,

434

Temperature scales

203

absolute zero

203

conversion of scales

203

Temperature of battery

Test curves for storage batteries

159

Test discharge

134

Testing, adjustment, and main-

tenance of starters

III,

202

causes of failure

III,

202

solving troubles

III,

204

testing

III,

203

trouble eliminated by efficient

devices

III,

. 202

Testing armatures for Delco

system

III,

, 415

Testing cut-outs, Delco

III,

, 408

Note.— For page numbers see foot of pages.

421

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INDEX

Vol. Page

Testing field coils, Delco III, 420

Testing generator with ammeter IV, 127

Testing ignition system III, 203

Testing oils for acid, etc. I, 337

Tests of wiring, Delco III, 405

. Thermal conductivity IV, 434

•Thermodynamics of steam V, 208

Thick vs. thin battery plates V, 34

Three-quarter elliptic springs II, 98

Three-quarter floating axle II, 156

Throttle valves I, 113'

Timing the Knight motor I, 290

Tire construction II, 241

bead II, 242

composition and manufacture II, 241

tire valves II, 243

Tire repair equipment II, 245

Tire repairs II, 245

inner tube repairs II, 257

inside casing forms II, 251

layouts of equipment II, 253

materials II, 257

outer shoe, or casing, repairs II, 260

re-treating vulcanizers II, 252

separate casing molds for patch

work II, 249

side- wall vulcanizer II, 251

small tool equipment II, 255

types of vulcanizing outfits II, 247

vulcanizing kettles II, 250
vulcanization of tires for repair

man II, 245

Tire valves II, 243

Tires II, 213; IV, 3S5; V, 287

Tires and mileage V, 156

improper inflation V, 161

kinds of tires V, 157

new tire equipment V, 160

test curves V, 159

Tool equipment for public

garages II, 349

Torque bar and its function II, 145

Tracing for grounds III, 338

Tracing a ring knock I, 70

Trailers V, 341
Transmission II, 137; V, 312

adjustment I, 413

Note. — For page numbers zee foot of pages.

Vol. Page

ransmission (continued)

bearings

413

chain drive

gear drive

driving reaction

II,

147

location

399

lubrication

412

Mack

315

operation

412

silent chain

317

similarity to gasoline practice V, 59

sliding-gear type V, 313

slip joints II, 139

stands I, 429

torque bar and its function II, 145

types II, 140

units in final drive II, 137

universal joints II, 138

use of "dog" clutches V, 315

usual gear reduction V, 59

Transmission and regulation de-
vices III, 305
automatic engagement III, 309
back-kick releases III, 312
clutches III, 310
driving connections III, 308
electric horns III, 319
fuses III, 317
installation III, 305
switches III, 313

Transmission troubles, summary

of I, 434

adjusting annular bearings I, 435

change-speed lever indicates

some impediment

in transmission I, 434

lubricating transmission gears I, 434

Transmission troubles and repairs I, 423

care in diagnosis I, 420

cleaning transmission gears I, 428

gear pullers I, 425

handy spring tool I, 431

heating I, 424

lifting out transmissions I, 429

noise in gear operation I, 423

poor gear shifting I, 426

possible transmission troubles I, 432

422

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INDEX

Vol. Page
Transmission troubles and repairs
(continued)
pressing gears on shafts I, 425

saving the balls I, 431

transmission stands I, 429

working on bearings I, 430

Truing brake drum on gasoline car II, 189
Tubular axles II, 65

drop-forged ends II, 65

Twelve-volt; single-unit, Disco III, 425
dynamotor III, 425

operating devices III, 425

regulation III, 425

Twelve-volt; single-unit; single-
wire, Dyne to III, 425
dynamotor III, 425
instructions III, 426
Twelve- volt; single-unit; single-
wire
Simms-Huflf

change of voltage
dynamotor

dynamotor connections
instructions

instruments
regulation
Splitdorf
dynamotor
wiring diagram
starting switch
Westinghousc
control
dynamotor
instructions
regulation
wiring diagram
wiring diagram
Twelve- volt; single-unit; two-
wire (early Wagner
model) IV,

control, transmission IV,

dynamotor IV,

instructions IV,

regulation IV 7 ,

firing diagram IV,

Twelve-volt; two-unit ; single-wire

Bosch-Rush more 111,

Note. — For page numbers sec foot of pages.

IV,
IV,
IV,
IV,
IV,
IV,
IV,
IV,
IV,
IV,
IV,
IV,
IV,
IV,
IV,
IV,
IV,
IV,

47
49
47

48
52
47
47
55
55
55
51
89
89
89
89
89
89
52

75
75
75
79
75
75

372

Vol. Page
Twelve- volt; two-unit; single- wire
Bosch -Rush more
(continued)
generator III, 37*2
instructions 111, 376
instruments and protective de-
vices III, 374
regulation III, 372
starting motor ' III, 372
wiring diagram III, 376
Twenty-four-twelve-volt, and
twlevc -six-volt ;
single-unit; two-
wire U. S. L. IV, 61
generator-starting motor IV, 61
instructions IV, 64
instruments and protective de-
vices IV,* 63
regulation IV, 62
U. S. L. 12-volt system IV, 73
U. S. Nelson system IV, 75
variations IV, 61
wiring diagram IV, 64
Twin-cylinder motor IV, 395
Twisted camshafts I, 285
Two-cylinder motors IV, 328
Two- wheel types of trailers V, 341
Typical valve actions I, 250

Unconventional types of springs II, 103

electric car springs II, 107

• Ford II, 106

Knox II, 104

Locomobile II, 107

Marmon II, 103

semi-elliptic truck springs II, 104

Winton II, 105

Unit wheel drives V, 277

balanced drive V, 280

couple-gear truck drive V, 278

Universal joint housings II, 164

Universal joints II, 138

U. S. L. 12-volt system IV, 73

fuse blocks IV, 73

starting switch IV, 73

U. S. Nelson system IV, 75

423

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INDEX

Vol. Page
Use of blow-torch in soldering

Vacuum brakes on gasoline cars
Valve caps
Valve enclosure
Valve gears

throttling and reversing

types of gears
Valve guides
Valve-stem clearance
Valve timing

exhaust-valve setting

relation of settings in each
cylinder

system applies to all types of
motors

valve-stem clearance
Valve timing for motorcycles

getting valve timing with scale

marking flywheels automobile
practice

marking gears

opening of valves not on dead
center
Valve troubles of motorcycles

removing valves
Valves I, 241;

Ventilation of public garages
Venturi-tube mixing chamber
Volt-ammeter
Voltage

after charging

drop

standards

tests
Voltage and spark control devices

charges in ignition methods

coils and vibrators

condenser

contact makers, or timers

distributor

hydraulic analogy for ignition
system

spark plugs
Vulcanization of tires for repair

Note. — For page numbers see foot of pages.

Vol. Page

II,

372

Vulcanizing kettles

horizontal type

II, 250

large vertical type

11, 250

II,

183

283

275

219

Wagner starting system

IV, 75

219

six-volt; two-unit

IV, 83

219

twelve-volt; single-unit; two-wire

282

(early model)

IV, 75

262

Water cooling

I, 300

260

anti-freezing solutions

I, 313

263

circulation

I, 307

fans

I, 312

263

radiators and piping

I, 303

water-jacketing

I, 301

264

Water-jacketing I,

116, 301

262

built-on jackets

I, 302

IV,

393

internal jackets

I, 301

iv,

394

welded applied jackets

I, 302

Water supply for public garages

II, 333

IV,

394

Water-tube boilers

V, 234

IV,

393

Webber automatic carburetor

I, 155

Welding blowpipes IV

, 407, 416

IV,

394

injector blowpipes

IV, 407

iv,

389

pressure blowpipe

IV, 407

IV,

390

welding heads and tips

IV, 416

iv,

382

working pressures

IV, 417

II,

333

Welding brass and bronze

IV, 475

118

Welding breaks in cylinders

I, 53

163

Welding copper

IV, 473

III,

303

Welding different metals

IV, 434

aluminum

IV, 468

III,

brass and bronze welding

IV, 474

III,

298

cast aluminum welding

IV, 471

iv,

253

cast-iron welding

IV, 459

III,

copper welding

IV, 472

III,

malleable-iron welding

IV, 467

III,

100

pre-heating

IV, 440

III,

104

properties of metals

IV, 434

III,

sheet-aluminum welding

IV, 469

III,

103

steel welding

IV, 443

Welding process for cast iron

IV, 463

III,

109

Welding process in sheet-aluminum

III,

104

welding

IV, 470

Welding rods IV,

460, 468

11,

245

Welding shafts and cases

I, 94

424

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INDEX

Vol. ]

Page

Westinghouse Ford starter

IV,

162

ignition

IV,

174

ignition unit

III,

181

lighting and starting switches

IV,

170

mounting starter

IV,

163

operating instructions

IV,

176

wiring

IV,

170

Westinghouse starting and light-

ing system

IV,

six-volt; double-unit; single-

wire

IV,

twelve- volt; single-unit; single-

wire

IV,

Wheel pullers

II,

211

Wheel troubles and repairs

II,

211

Wheels

II,

190

commercial-car wheels

II,

204

pleasure-car wheels

II,

192

White gasoline delivery wagon

299

Whiton gear-cutting machine

436

Wiring

III,

172

effect on lights

III,

175

importance of voltage drop

III,

174

operating troubles

IV,

188

Wiring diagram III, 351, 357, 376,

389, 399,

429,

435

Apperson

III,

360

Buick

III,

392

Cadillac

III,

389

diagrams for single-wire systeir

HI,

330

explanation of

HI,

327

Heinze-Springfield

III,

452

Hupp

HI,

360

Jeffery

III,

357

Leece-Neville

IV,

North East

IV,

Vol. Page

Wiring diagram (continued)

Scripps-Booth III

Simms-Huff IV

Splitdorf IV,

Wagner IV, 75,

Westinghouse IV, 89,

Winton III

Wire wheels for pleasure cars II,

Wobbling wheels II

Wood frames II

Wood wheels II, 192,

Worm-gear transmission V,

Worm drive V, 63,
advantages of worm-gear trans-
mission
details of worm drive, rear

axle and brake V>

development V, 63

efficiency of worm gears V,
standard types of worm gears V,

Worm steering-gear types II

bevel pinion and sector II

Hindley worm gear II

worm and full gear II

worm and nut II

worm and partial gear II

worm and worm II

Zenith carburetors I,

changing the compensator I,

changing the main jet I,

duplex model adjustments I,
horizontal type adjustments

and changes I,

slow-speed adjustment I,

360

357

196

205

274

321

323

325

324

127
128
128
132

131
131

Note. — For page numbers ace foot of pages.

425

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