DEPARTMENT OF THE INTERIOR, CANADA
FORESTRY BRANCH
t-NRLF
B 3 372 7flfl
METHODS OF COMMUNICATION
ill
ADAPTED TO FOREST PROTECTION
OTTAWA
THOMAS MULVEY
PRINTER TO THE KING'S MOST EXCELLENT MAJESTY
1920
Price, $1.00.
i. • Forestry - Main Library
DEPARTMENT OF THE INTERIOR, CANADA
FORESTRY BRANCH
METHODS OF COMMUNICATION
ADAPTED TO FOREST PROTECTION
BY
W. N. MILLAR, B.S, M.F,
M
OTTAWA
THOMAS MULVEY
PRINTER TO THE KING'S MOST EXCELLENT MAJESTY
1920.
79211— A
n
. - Forestry - Main Library
The methods of forest telephone eC'riotraeision' describVd in this manual have been
adopted almost without change from the " Instructions for Forest Officers " as issued
by the United States Forest Service, Department of Agriculture, in its publication
entitled " Telephone Construction and Maintenance OTI the National Forests." With
the permission of the Forest Service a considerable portion of these instructions has
been reprinted herein and forms the bulk of Chapters VII, VIII, IX, XI, XII, and
XVI, as well as parts of other chapters. Most of the diagrams illustrating telephone
construction methods are also reproduced from the same publication. A few were
adapted from a special circular of instructions prepared by the District Forester,
District 5, United States Forest 'Service and certain material in the text was secured
from the same circular.
Other important publications from which material has been derived are the
following: "Systematic Fire Protection in the California Forests," Dubois; "Fire
Protection in District 1," Silcox; "Manual of Visual Signalling," United States
Signal Corps; " Trailing Manual— Signalling 1915," British War Office.
In only a few cases, however, has it been possible to quote. In addition, a large
number of works on special phases of the subject have been consulted and these are
for the most part included in Appendix B.
Persoiial assistance of the greatest value has also been received from Mr. E. H.
Finlayson, District Inspector of Forest Reserves for Alberta, who has aided in the
determination of the general plan of the manual and has particularly assisted by
criticism of Chapter XIV; from Mr. R. B. Adams, Telephone Engineer, United States
Forest Service, Missoula, Montana, who has offered many valuable suggestions and
furnished much of the material contained in Chapters X and XIII; from Mr. J.
B. Somers, United States Forest Service, in connection with the use of the heliograph
and flag by the Service, and from many field officers of the United States Forest
Service and the Dominion Forestry Branch with whom the author has been associated
in forest administration.
79211— A!
ABBKEVIATIONS
A. W. G.=American Wire Gauge (Brown & Sharpe)
B. B. = Best Best iron wire
B. & S. = Brown & Sharpe wire gauge
B. I. G. = British Imperial Gauge
B. S. M. G. = Birmingham Sheet Metal Gauge
B. W. G. = Birmingham Wire Gauge
D. B. = Double-Bitted, as of an axe
D. F. B- = Dominion Forestry Branch
E. B. B. = Extra Best Best iron wire
E. M. F. = Electro-Motive Force
N. B. S. G. =New British Standard Gauge
S. B. = Single-Bitted, as of an axe
U. S. S. M. G. = United States 'Sheet Metal Gauge
IV
CONTENTS
%
Page
Introduction XV
Part I — Communication in Specialized Forest Protection
CHAPTER I — SPECIALIZED FOREST PROTECTION.
Sec.
1 Specialization Defined 1
2 Communication Defined '.'. . 2
3 Present Protection Methods 2
4 Analogy to Military Operations 3
5 Functions of a Forest Protection Force 3
6 Prevention of Forest Fires 4
7 Detection of Forest Fires 5
8 Suppression of Forest Fires 7
9 Supervision of Protection Forces 8
10 Duties of Supervising Officers 8
11 Duties of Suppression Staff Officers '...''.. 10
12 Duties of Suppression Line Officers. 12
13 Value of Communication System in Field Operation 13
CHAPTER II — METHODS OF CONVEYING INFORMATION TO A DISTANCE.
14 Variety of Methods Available -..'•• 14
15 Types of Visual Signals 14
16 Types of Audible Signals >•'''•• 15
CHAPTER III — ADAPTING COMMUNICATION METHODS TO SPECIALIZED FOREST PROTECTION
17 Speed and Certainty in 'Communication Essential 17
18 Method Must be Adapted to Conditions of Use 17
19 Control Units Requiring Intercommunication Facilities 17
20 Communication Requirements of Control Units. . 19
21 Superiority of the Telephone Evident. .'....' 20
22 Auxiliary .Methods Often Required 20
Part II— Forest Protection Telephone Lines
CHAPTER IV — PLANNING THE TELEPHONE SYSTEM
«
23 Importance of Preliminary Plans 23
24 Plans Must Be Based on Definite Area 23
25 Primary Stations Requiring Service 23
26 External Versus Internal Systems 24
27 Connections to Lookout Stations 26
28 Test Stations 26
29 Relay Stations 26
30 Alternative Routes 26
31 Secondary Strategic Points • 27
v
vi METHODS OF COMMUNICATION FOR FOREST PROTECTION
CHAPTER V — SELECTING THE TYPE OF CONSTRUCTION
Sec. Page
32 Pole-line 'Construction 27
33 Tree-line Construction 27
34 Construction Methods Contrasted 28
35 Relative Cost of Different Types 28
36 Sketch of the Development oi Tree-line Methods 29
37 Influence of Timber Conditions on Choice -of Construction Type 30
38 Grounded Versus Metallic Circuits 32
CHAPTER VI— TELEPHONE CONSTRUCTION POLICY IN DOMINION FOREST EESERVES
39 Construction by the Forestry Branch 33
40 Co-operative and Private Lines 33
41 Use of Forestry Branch Lines 34
42 Telephone Improvement Plans 35
43 Standard Methods 35
44 Standard Materials 36
CHAPTER VII — OPERATIONS PRELIMINARY TO CONSTRUCTION
45 Factors Influencing Location 42
46 Survey of Route 42
47 Securing Right of Way 42
48 Clearing Right of Way 41
49 Transportation and Distribution of Materials 45
50 Organization and Equipment otf Construction Crews. 46
CHAPTER VIII — POLE-LINE CONSTRUCTION
51 Selection of Poles 47
52 Skidding and Seasoning. . 47
53 Preservative Treatment 47
54 Length of Poles 49
55 Erection of Poles 49
56 Bracing and Guying . .. 54
57 Line Construction 59
CHAPTER IX — TREE-LINE CONSTRUCTION
58 General Principles 68
59 Selecting Trees .and Route t 68
60 Line Construction 69
CHAPTER X — EMERGENCY LINES, CONSTRUCTION AND USE
61 Use in Forest Protection 74
62 Line Construction 74
63 .Maintenance. 76
14 Taking up Wire 76
CHAPTER XI — FOREIGN LINES, CROSSINGS, AND CONNECTIONS
65 Location on Poles of Foreign Lines 78
66 Crossings .. 78
67 Connecting Forestry Branch Lines with Private Lines or Exchanges. ... 82
68 Branch Lines.. 8°
CONTENTS „ vii
CHAPTER XII — INSTALLATION OF FIXED EQUIPMENT
Sec. Page
69 Wall Sets : 85
70 Condensers 85
71 Dry Batteries 85
72 Protectors 88
73 " Grounds " 90
74 Wiring 92
75 Lookout Station Telephone Sets . . . 94
76 Howler and Condenser for Vibratory Signalling 96
77 Coils .. .. 98
78 Special Installations 99
CHAPTER XIII — INSTALLATION OF TEMPORARY EQUIPMENT
79 Types of Portable 'Sets 107
80 Forestry Branch Portable Telephone 108
81 Adams Hand Set 110
82 Emergency Communication Kits 114
83 Temporary Connection to Permanent Lines 115
CHAPTER XIV — MAGNETO TELEPHONE
84 Introduction 117
85 Definition of Electrical Terms 118
86 Parts of the Magneto Telephone 121
87 Methods of Connecting Telephones to Line 137
CHAPTER XV — OPERATION
88 Operating Rules 140
89 Code Signalling 140
CHAPTER XVI — MAINTENANCE
90 General Principles 142
91 Line 142
92 Apparatus 145
93 " Trouble " 152
CHAPTER XVII — TELEPHONE " DON'TS "
94 Construction 157
95 Installation 158
96 Operation 158
97 Maintenance. . . 159
Part III— Forest Protection Heliographs and other Signalling Apparatus
CHAPTER XVIII — HELIOGRAPH
98 The Instrument 160
99 Use in Forest Protection 160
ICO Range and Speed 161
101 Types of Heliographs 162
102 Heliographs at Lookout Stations 165
103 Heliographs on Patrol Routes 109
viii METHODS OF COMMUNICATION FOR FOREST PROTECTION
CHAPTER XIX — USE OF THE GODWIN HELIOGRAPH
Sec. Page
104 Parts of the Instrument 169
105 Using the Godwin Heliograph ' .. 170
CHAPTER XX — SIGNALLING WITH THE HELIOGRAPH
100 Selecting a Station 173
107 Position of Operator 173
108 Maintenance of Adjustment 174
109 Opening Communication 174
110 Working at Short Ranges 175
111 Working Through Haze and Smoke 175
112 Heliograph Codes 175
113 Instructions to Operators 179
114 Care of Instruments . . 180
115 Training Operators 180
116 Heliographing by Moonlight and Artificial Light 181
CHAPTER XXI — NIGHT SIGNALLING
117 Signalling Lanterns 182
CHAPTER XXII — FLAG
118 General Remarks 186
119 Equipment Required 186
120 Range and Speed 186
121 Use in Forest Protection 187
CHAPTER XXIII — USING THE FLAG
122 General Remarks . . 188
123 Selecting a Station 188
124 Wigwag Signalling 189
125 Rules for Operators and Conventional Signals 191
126 Wigwag Codes 191
127 Semaphore Signalling 191
CHAPTER XXIY — MESSAGE CODES
128 Purpose oi Codes 194
129 Use in Forest Protection \ 194
130 Combinations Available 194
CHAPTER XXY — DANGER SIGNALS
131 Risk in Fire-fighting 195
132 Use of Danger Signals 195
133 Code of Danger Signals 195
134 Miscellaneous Uses of Shot and Whistle Signals 196
CONTENTS
Appendices
APPENDIX A — OUTFIT FOR TELEPHONE CONSTRUCTION CREW
Page
1 Ten-man Crew for Telephone Construction 196
2 List of Line Supplies 197
3 List of Station Supplies 197
4 List of Construction Tools 197
5 List of Tentage .. 198
6 List of PTOvisions 198
7 List of Kitchen Equipment 198
APPENDIX B — USEFUL BOOKS OF EEFERENCE
1 Science of Telephony 199
2 Line Construction 199
3 Preparation and Preservation of Poles 200
4 Military Signalling and Telephony 200
5 Telephone Troubles 200
6 Specialized Forest Protection 200
7 Periodicals 201
8 Trade Catalogues and Handbooks 201
APPENDIX C — TELEPHONE COSTS
1 Factors Involved i-n the Estimation oif Costs of Pole and Tree Telephone
Lines 201
2 Approximate Costs of Supplies and Average Time Required for Various
Operations in Telephone Line Construction 202
APPENDIX D — EULES FOR WIRES CROSSING EAILWAYS AND TRANSMISSION LINES
Order No. 231 Board of Railway Commissioners of Canada 203
APPENDIX E — FORESTRY BRANCH STANDARD SPECIFICATIONS
1 Specification's for Galvanizing 209
2 Specifications for Gal van izedr iron Telephone Wire 210
3 Specifications for Hard-drawn Copper Telephone Wire 211
4 Specifications for Emergency Wire 211
5 Specifications for Rubber-covered Wire. 212
6 Specifications for Glass Insulators 213
7 Specifications for Split Tree Insulators 214
8 Specifications for Poles 215
9 Specifications for Wooden Spools 'for Emergency Wire 217
10 Specifications for Creosote 217
11 Specifications for Wooden Brackets 218
12 Specifications 'for Outdoor Protector Mounting-boxes 219
APPENDIX F — SOLDERING
Methods and Materials.. 219
METHODS OF COMMUNICATION FOR FOREST PROTECTION
APPENDIX G — USEFUL TABLES.
Page
1 Weight of Cedar Poles of Various Lengths and Top Diameters 221
2 Number of Poles of Different Sizes Required to Make up a Carload Lot. . 221
3 Comparison of Wire Gauges 222
4 Tensile Strength of Bare Copper Wire 223
5 Properties of Hard-dra'wn Copper Telephone and Telegraph Wire 223
6 Properties of Bimetallic Wire 224
7 Properties of Galvanized Telephone and Telegraph Wire 224
8 Properties of Galvanized Steel Wire 225
9 Properties, of Rubber-covered, Lead-incased Copper Cables 225
10 Properties of Standard Wire for Telephone Construction on Dominion Forest
Reserves 226
Index 227
CONTENTS Xi
Illustrations
Fig. . Page
1 Lookout station on a Dominion forest reserve in British Columbia 5
2 Steel lookout tower on a Dominion forest reserve in Saskatchewan 6
3 External telephone system on a forest reserve 24
4 Internal telephone system on a forest reserve 25
5 Mobley wire-CTadle as used with two coils 43
6 Mobley wire-cradle as us-ed with one coil 43
7 Mobley wire-cradle . . 44
8 Klondike pack-.frame as used for packing wire 4o
9 Pole-steps 51
10 Location of brackets on pole 51
11 Definition of rake 53
12 Definition of pull 53
13 Setting a pole. 54
14 Method of bracing 55
15 Method of guying , 56
16 Kc-ck guy bolt 57
17 Method of using guy stub 58
18 Method of ground bracing 58
19 Tripod line .supports 59
20 Home-made reel 61
21 Transposition of wires, metallic circuit 62
22 Method oi making regular tie for iron wire 64
23 Method of making " figure 8 " tie for iron wire. 64
24 Method of dead-ending iron wire 65
25 Method of dead-ending hard-drawn copper wire 65
26 Method of making regular tie for hard-drawn copper wire 66
27 Method of making " figure 8 " tie for hard-drawn copper wire 67
28 Method of splicing iron wire (Western Union joint) 67
29 Method of splicing 'hard-drawn copper wire 67
30 Zigzag system of alignment. 69
31 Reverse curve system of alignment 69
32 Split tree insulator attachment and cmsstie ". . . . 71
33 Method of dead-ending on tree lines . . . . 72
34 Method of tying up emergency wire 75
35 Method of making temporary splice in emergency wire 77
36 Emergency wire reel, open and folded 77
37 Method of crossing transmission lines 79
38 Method of connecting branch line to main line when both are galvanised-
iron wire 82
39 Method of connecting branch line to main line 'when both are hard-drawn
copper wire 83
40 Method of connecting branch line to main line in tree construction. ... 84
41 Wiring diagram of standard wall set 86
42 Standard telephone installation 87
43 Method of connecting dry cells for a telephone. 87
44 Method of installing line fuse when required 88
45 Wiring diagram for telephone station 90
xii METHODS OF COM MUNI CATION FOR FOREST PROTECTION
Fig. Page
46 Method of making entry to building from main line 93
47 Wiring diagram of lookout station telephone set. 95
48 Lookout station telephone set installed in the field 96
49 Method of connecting lookout station telephone to line and ground 97
50 Method of connecting howler ,and condenser • 98
51 Method of installing lavite coil to drain line of static electricity 99
52 Method of installing a repeating coil on a pole 100
53 Legend 101
54 Switching station, first method 102
55 Switching station, second method 102
56 Wiring -and connections on 47^A repeating coil.. .... .. 103
57 Phantom circuit 104
58 Connecting grounded line to metallic line through a repeating coil without
switches . . . 105
59 Connecting grounded line to metallic line by use of switches and two
telephones ..'.. .: . 105
60 Connecting grounded line to metallic line by use of switches and one
telephone . 106
61 Method of using one wire for simultaneous telegraphy and telephony. . . . 107
62 Forestry Branch portable telephone set (1375-A) 109
63 Wiring diagram of Forestry B-ranch portable telephone ........ 110
64 Adams hand set (1004-A) with carrying case Ill
65 Wiring diagram of the Adams' hand set (1004-A) . . .'! . . . . Ill
66 Forest officer preparing to use the Adams hand set with Cree knife 'for ground
rod . . ..:..:.... . . .... . . . . 113
67 Forestry Branch emergency communication kit No. 1-A. . .... ...... . . 114
68 Wiring diagram of No. 1-A kit .. .. .. '. .. •• 115
69 Forest ranger using the No. 1-A emergency kit • • • • • '•' '.'. . • • • • • • 116
70 Bipolar hand receiver .!'.... .\! .. ..'.... 122
71 Longitudinal section of bipolar .receiver.. .. .. .. .. ../.^.'. 122
72 Diagram of telephone circuit, first stage .... .... . . .... 122
73 Solid-back transmitter and transmitter arm. .'.' .. . . . . .'. . . . . . . 124
74 Details of the solid-back transmitter '. . . . . . . 124
75 Diagram of telephone circuit, second stage ". 124
76 Telephone induction coil 126
77 Diagram of telephone circuit, third stage. 1 . . 126
78 Magneto generator, five-bar 127
79 Polarized ringer, unbiased type 128
80 Telephone switch-hook -''.V ".;. ' Ci :!.' . "• • '...' • • 130
81 Rolled condenser . . . . . . . . 131
82 Howler . . . . 132
83 Lightning protector for use where there are no power ox light wires 133
84 Protector with fuses for use where there .are power or light wires 134
85 Baby knife-switches: (a) Single pole, single throw (S.P.S.T.) ; (b) Double
pole, double throw (D.P.D.T.) 135
86 Method of inserting a metallic circuit section in a grounded line to overcome
induction disturbances 136
87 Diagram of a phantom circuit . . . 136
88 Telephones connected1 in -.series on a metallic line . 138
89 Telephones connected in series on a grounded line. 138
90 Connecting bridging telephone on ,a grounded line 139
91 Connecting bridging telephone on a metallic line.. 139
92 Method of installing test station indoors 143
93 Method of installing a' test station on a tree. . . . 144
94 Stub reinforcement of poles 146
CONTENTS xiii
Fig. Page
95 Receiver -test 148
96 Ringer of No. 127^F extension bell and Nos. 1317-P, 1317^8, 300-N, and 1336-J
-telephones 151
97 Wiring of No. 1317 telephone set 153
98 British Army type of heliograph, one-mirror 162
99 British Army type of heliograph, two-mirror 16-3
100 American Army type of heliograph, one-mirror 164
101 American Army type of heliograph, two-mirror 164
102 Forest Service type of heliograph, one-mirror 166
103 Forest Service type of heliograph, two-mirror 167
104 Map of California national forest showing heliograph system 168
105 Forest ranger sending message by heliograph 171
106 Acetylene signal lantern with tripod 183
107 Fischer high-power electric signalling lamp 184
1 108 Initial position in flag signalling • 189
109 " Dot " or (motion " 1 " in flag signalling 190
110 " Dash " or motion " 2 " in flag signalling 190
111 Semaphore alphabet, numerals, and special signs 192
112 Two-arm fixed semaphore code 193
Design of Forestry Branch standard pony glass insulator 214
Design of Forestry Branch standard split tree insulator .. 215
Design of Forestry Branch standard emergency wire spool 217
Design of Forestry Branch standard wooden bracket 218
Design of outdoor protector mounting-box 219
INTRODUCTION
This manual has a twofold purpose. Primarily, it is intended for the instruction
and guidance of those officers of the Dominion Forestry Branch who are charged witj
the protection of the forest reserves and other Dominion-owned timber and who find
rapid and reliable means of communication an indispensable adjunct to their work.
In order to fulfil this purpose, the various methods of communication which experience
has demonstrated to be best adapted for use in forest protection are dealt with in
detail, and the methods herein set forth are to be followed without deviation wherever
permanent lines of communication are established.
Particular attention is given to instructions for the building of forest telephone
lines. In some important respects these lines possess unique characteristics. The
distinctive requirements of telephone Communication for forest protection purposes have
been the subject of much intensive study and experiment during the past decade both
in Canada and the United States, and the equipment and methods of construction
which have been adopted or developed have been standardized by the United States
Forest Service and adopted by many state and private forest protection organizations
in both countries. These standard methods with slight modification to fit Canadian
conditions are set forth in detail in this manual and form the main body of the portion
devoted to the telephone.
It is felt, however, that information with regard to the usefulness of the telephone
and other means of rapid communication in forest protection is of timely interest to
all owners of timber in Canada. Thus far, there has been relatively little specialization
in the work of forest protection on Canadian timber-lands. The usual system followed
by both government and private owners has been to send out each year a large number
of fire rangers, each of whom works on a more or less independent basis. In many
cases a new crew is raised each year and in most cases dependence is placed on chance
and the native ability of the rangers for the prevention, detection, and suppression of
fires in their districts, without aid from special training, organization, or equipment.
There are a few notable exceptions to this practice but as a general rule forest
protection in Canada is handled by forces wholly lacking the training, organization,
or equipment necessary for the employment of modern specialized methods and is,
therefore, of necessity, costly and inefficient.
One of the prime essentials in the organization of fire protection on a specialized
basis, in contrast to the present non-specialized methods, is a reliable means of rapid
communication linking up all strategic points within the forest with those outside
of it and forming a network of lines of communication by which every unit of its
protection staff is in constant touch with every other unit, and the whole is in direct
communication with the chief ranger or other officer immediately responsible for the
protection work on the area. In this manual, the principal means by which this inter-
communication may be maintained in an unsettled timbered country are explained.
Naturally, wherever adequate commercial telephone or telegraph services exist they
will be employed, but these are of little importance in forest protection in Canadp
because settlement in timbered regions is extremely meagre.
xv
xvi METHODS OF COMMUNICATION FOR FORREST PROTECTION
Being intended for non-technical readers, it has been necessary in many instances
to elaborate points that might otherwise have been passed over very briefly. For the
same, reason a certain amount of repetition has been thought desirable. The aim has
been to bring together in one publication not only the details of telephone construction
and operation practice as exemplified on the Dominion forest reserves, but also all
available information on various communication methods that have proved to be
useful in connection with forest protection activities. It is believed that only one
subject of importance has been given very inadequate treatment and that is the
question of pole preservation. This, it is planned to treat in a supplementary
publication when certain investigations now being conducted are completed.
PART I
COMMUNICATION IN SPECIALIZED FOREST PROTECTION
CHAPTER I
; v: .^ •>« » ,». r
SPECIALIZED FOREST PROTECTION '.'
Section 1 — Specialization Defined- /A, i«. '>.? **'*>'•'•' *>•*'•
As applied to forest protection, specialization involves two primary modifications
of old style methods. These are, on the one hand, an extensive centralization of
executive authority in the hands of certain field officers who are responsible for the
protection of certain clearly defined forest tracts and, on the other hand, a classifi-
cation of the duties of the field staff into certain well-defined functions and the
assignment of special men to the performance of these special functions. This is best
understood, perhaps, by comparing the actual organization of the old style
forest protection staff with the modern specialized staff. In the more primitive
of the former the staff consists of a number of district chiefs or inspectors
each of whom is responsible for the general supervision of the patrol staff in a certain
area. These inspectors are most likely permanent employees. Under each is a
number of patrolmen or rangers, assigned either singly or in pairs, to a certain
subdivision of the inspector's district, called as a rule a " beat." Each of these
rangers is responsible for his own beat only and within that area he performs all the
functions of the fire prevention staff. The district chief or inspector is required to keep
moving from beat to beat principally for the purpose of ensuring that the rangers are
in the areas assigned to them and are performing their duties. In addition, he, being
a permanent employee and presumably more skilled in those duties than the temporary
staff, can assist the latter by advice and instruction. This extremely simple form of
organization has, however, only one point in its favour which is that it can be
employed where the field staff is wholly untrained or unskilled in modern protection
methods while no other form can be so employed. It is, therefore, particularly adapted
to regions where the subordinate protection staff consists of extremely low-priced
labour, as in India where natives are largely employed for this work. Where our own
standards of wages prevail, such a system to be effective must be tremendously
expensive. This is as inevitable in forest protection as it is in other forms of organized
human activity such as manufacturing, transportation, or military affairs, from all
of which in the modern world this system has long since disappeared.
'Contrasted with this method of protection are the various more or less elaborated
systems of specialization that have been developed by the leaders in forest protection.
These developments differ in no material respect from those that have taken place in
other large-scale activity but, owing to the nature of the work, they have followed more
closely the methods of organization employed in military operations rather than those
of most industrial activities. The most striking characteristic of a specialized staff
is that instead of being a constantly moving patrol, each man confined to a limited area
within which he performs all functions, it becomes very largely a stationary staff,
each member of which performs only one function but may extend his activities over
a large number of the old-time beats. Thus, instead of each man being individually
responsible for detecting fires, certain men are specially assigned to this work and
are located permanently on prominent lookout peaks or towers; instead of each man
being responsible for putting out such fires as occur, special men, selected, equipped,.
79211—1 1
2 METHODS OF COMMUNICATION FOR FOREST PROTECTION
and located with this one end in view are placed at strategic points and are despatched
only to such fires as are discovered by the lookout men; instead of each man getting in
his own supplies for himself or a fire-fighting crew, a special man operating over a
large area with suitable equipment and assistants takes care of all the supplies and
transportation. In short, to establish a specialized forest protection staff means
nothing more or less than the extension of division .of labour on the modern basis
of function to the work of protecting forests from fire.
Section 2 — Communication Defined
' ;W(Ken we : spp a£'; of ^communication in connection with forest protection we may
have in mind one or thf> .other of two rather distinct concepts. On the one hand,
communication' refers/to, the conveyance of materials or of men from one place to
another. In this sense communication becomes a problem of transportation and lines
of communication become roa«ds, railways, trails, etc. With this type of communi-
cation, although it is of vast importance in forest protection, this manual is not
concerned.
Communication in the other sense means the conveyance of information from one
place to another. Obviously this does not necessarily involve any transfer of material
substance, and lines of communication become telephone or telegraph wires, wireless
installations, or signals of an almost endless variety. In this sense, communication
is one of the prime essentials in specialized forest protection. Without well-developed
means of transmitting information rapidly between all the numerous elements of a
specialized force it is wholly impracticable to employ the distinctive features of
specialized organization, and entire responsibility for all lines of work must necessarily
be left in the hands of the patrolman, the least trained, and most poorly paid and
equipped man in the whole force. This is obviously inevitable, however, in the
absence of lines of rapid communication. At the same time it must be kept in mind
that forest telephones and other modern devices for securing intercommunication do
not of themselves produce specialization in a forest protection staff, but are merely a
necessary mechanical device through the use of which functional organization and
centralized control are rendered feasible.
Section 3 — Present Protection Methods
It is well recognized in Canada that forests if they are to be kept from burning
up must have some kind of systematic protection during that portion of the year
generally referred to as the " fire season." The extent of protection attempted largely
depends upon the enlightenment of the owner of the timber, the value placed upon it
and the fire danger or risk. This last is an extremely complex element made up of
several factors which vary with the season, the character of the forest, the local causes
of fire, and other local conditions which tend to favour or to obstruct the protection
work. It is equally well recognized in the forested regions of Canada that the only
kind of protection that has even a remote chance of success is patrol by a force of
specially employed fire rangers. The patrol of timber-lands has been a feature of fire
.protection in certain parts of Canada for more than thirty years. In other parts it
is only of recent origin, while very large areas in all parts of the country, bearing a
young growth whose value and vital national importance are unrealized, are as yet
wholly unprotected. A careful study of most of these patrol forces, however, reveals
the fact that they are organized and operated on extremely individualistic lines. Some
of the very largest operate almost without a directive staff and in no case has there
as yet been developed a staff capable of making a close scientific study of this problem
of fire protection, resolving it into its elements and building up on a basis of known
.facts a business-like organization and mode of procedure. In almost every case a
SPECIALIZED FOREST PROTECTION 3
forest protection force in Canada consists simply of an indefinite number of more or
less qualified men hired each year for the fire season only, and sent into the woods with
only the most meagre instructions. In general they are told to prevent or to detect
and suppress, so far as possible, forest fires in a specified district. Between rangers
even in adjoining districts there is little or no relationship. There is practically no-
differentiation of duties and no guidance or supervision except a very occasional visit
of inspection, primarily to determine that they are actually present in their district
and are not employed at some other work. Even this is successful only to a very-
limited extent because of the inherent difficulties of maintaining close personal super-
vision over a force which of necessity is widely scattered over a vast area of undeveloped
country.
The total annual expenditure for forest protection by all agencies in Canada is
probably not less than $1,500,000. Single agencies spend as much as $350,000 per
annum and employ 800 to 1,000 men annually. The value of the resource protected is
of immense importance to the nation since fully 65 per cent of the country is capable
of producing no other form of useful commodity. This resource is the raw material
for the second largest industry of Canada. From this may be gained some idea of the
relative importance of a scientific study of the business of protecting forests from fire.
Section 4 — Analogy to Military Operations
It requires but little knowledge of the operations involved in forest protection
under conditions existing in Canada to appreciate the striking resemblances which
exist between this work and military operations on a large scale. It is noted at once
that there exist the same problems of transportation, of commissary and supply, of
scouting and reconnaissance, of intercommunication, of camp management, and the
handling of men on the fire-line. Also there are frequently involved problems in
field engineering, and in animal management. Further, it is readily possible to
divide the actual process of placing a forest fire under control by frontal attack, flank-
ing trenches, or back-fires into two main sets of operations, namely tactical and
strategical. The present is perhaps an opportune time to point out the vital import-
ance of organization and discipline, of special training for individual units, of perfect
equipment, and of a skilled and scientific directive staff in military operations. Months,
even years, are spent in training men for the least responsible of military positions
and we know that an army without this highly perfected organization and equipment,
no matter how individually excellent, is a pitiable thing before a modern military
machine. It is little realized, however, that forest protection, which in all its essen-
tial operations bears such a striking resemblance to military operations, is susceptible
of just as intensive study and development and that an unspecialized fire-ranger staff
is, in its own sphere, just as pitiable an object when compared to a highly specialized
staff as is an untrained ill-equipped army when compared to our modern troops.
As is well known, the extent and perfection of control maintained in modern
military operations is largely the result on the one hand of the perfection of functional
control secured through the General Staff and on the other of two elements of
mechanical eouipment, the gasolene engine as applied to transportation, and the tele-
phone and telegraph as employed in intercommunication. It is one of the aims of
this manual to indicate how these same highly developed means of intercommunication
may be applied at small expense to the operation of directing forest protection forces.
Section 5 — Functions of a Forest Protection Force
A careful analysis of the operations involved in the protection of forests from
fire reveals the fact that a fire-control force exercises four principal functions. These
may be called Prevention, Detection, Suppression, and Supervision. In an unspecial-
79211— H
A METHODS OF COMMUNICATION FOR FOREST PROTECTION
ized staff each member of the staff exercises all four functions. Naturally there is no
organized staff so completely unspecialized that there is absolutely no differentiation
of functions performed by different members, but nearly* all of the forest protection
forces of Canada ave so little specialized that the overwhelming majority of the staff
actually does have all these functions to perform. As in other industries so in forest
protection, non-specialization means independence of action and lack of close co-opera-
tion. Thus we find that practically all fire rangers employed in Canadian forests are
independent units, each supreme in his own district, performing individually all
functions of fire control, and neither assisting nor receiving assistance from any other
unit.
Where specialization has been adopted, however, the whole organization is
radically different. Specialization is the basis of modern industry, and the gain in
efficiency that resulted from the industrial revolution is no more striking than is the
improvement that results from the adoption of similar specialization in forest protec-
tion. Obviously, no other result could reasonably be anticipated.
Specialization in forest protection is secured by employing separate units to
perform each of the distinct functions revealed by the analysis of the operations of
forest protection. It is neither possible, nor necessary, to differentiate functions
absolutely in all cases, but instead of each member of the control force performing all
functions each is given one as a primary function and exercises the others only to a
very minor degree, if at all.
Section 6 — Prevention of Forest Fires
The function of Prevention, as the name would indicate, includes all those
activities whose aim is to ensure that fires do not start in the forest. Statistics of
the causes of forest fires, upon which all prevention plans must be based, show that
for the eastern part of the country human agencies are responsible for at least 95
per cent of forest fires, while in the West about 80 per cent are thus caused. This
difference is due to the lightning-caused fires which are relatively more numerous in
the mountainous regions of the West. Fires due to human causes may be considered
almost wholly preventable, and a forest protection staff must be prepared to make an
exhaustive study of the causes of the fires with which it has to deal and to apply
the necessary remedies. Prevention of forest fires involves a whole host of considera-
tions mostly beyond the range of this discussion and even in actual application largely
beyond the influence of the direct control forces in the woods. Certain preventive
measures, however, belong primarily to the woods staff. Such, for instance, are advice
and warning to forest travellers and tourists. This is of very great importance in
many forested regions of Canad'a. A specialized forest protection force will have
certain of its members specifically assigned to this duty wherever the directive staff
determines, as a result of a careful study of fire records, that such preventive measures
are needed. In maintaining this observation of tourists and other travellers a well-
developed system of communication by which the patrol force is kept constantly
informed of the entrance of parties into the forest and of their movements while
there is of immense value. By means of it every person in the force is enabled to
contribute indirectly to the prevention work and to assume this as a secondary function
without in any way interfering with whatever happens to be his primary function.
Similarly, the supervision of " clearing " fires employed! by settlers, an extremely
frequent cause of disastrous forest fires, is preventive in nature, and many other
activities of this kind must be provided for, according to local conditions. In all
cases, however, it is necessary to emphasize that the fundamental basis for scientific
and effective prevention work is an accurate knowledge of fire causes in any given
region. This is best secured by rigid investigation of all fires that occur and the
accumulation of statistics of causes over a period of years.
SPECIALIZED FOREST PROTECTION 5
Section 7 — Detection of Forest Fires
The method of performing the function of Detection has to some degree become
a distinctive characteristic of a specialized staff. In the usual type of organization
with little or no internal co-operation or interdependence of units, each ranger must
depend upon himself alone to detect and locate all fires in his district. To accom-
plish this he adopts various methods according to the nature of the country and
forest, the causes of fires, and his own energy, experience, and ingenuity. To some
extent he relies upon reports received from various volunteer sources, supplementing
this with patrol of routes of travel, and1, if the region is favourable, with observations
from commanding peaks, ridges, or even unusually tall trees. If he sights a smoke from
a distance he can determine its location only by his knowledge of the country, aided
by a map if he has one and knows how to use it. In most cases his determination is
likely to be only a mere approximation and much time is lost in searching for the
fire and making the exact location. This done, he must then undertake its suppres-
Fig. 1 Lookout station on a Dominion forest reserve in British Columbia
sion either alone or with such assistance, often inadequate, as he is able to summon
to his aid. During the Suppression period, the protection of his district will most
lively be left entirely to chance. The fatal weakness of this system is the slowness
and uncertainty with which it operates. One of the most efficient fire-preventive
organizations in the world has as its motto " Minutes Count " and nowhere in the
course of a fire do they count more disastrously than in the first few hours. Prac-
tically all forest fires start as mere sparks. A neglected or half-extinguished camp-
fire, a carelessly dropped match, the spark from a pipe or an engine, or some other
similar insignificant source gives rise to the great bulk of disastrous fires. At the
start and for some little time afterward, according to the weather, the season, and
other local conditions, all such fires are easily within the power of one man to
extinguish. But as they increase in size they increase even more rapidly in intensity.
What was at first only a spark soon becomes a conflagration which only a very large
crew of mon can make headway against. The lesson, therefore, that every ranger
6
METHODS OF COMMUNICATION FOR FOREST PROTECTION
has learned is that the way to prevent large fires is to extinguish them when they
are small — an obvious lesson — the accomplishment of which task is the primary
purpose of specialization in forest protection.
There are in general but two ways to ensure that all fires will be extinguished
in their incipiency. The one is to put in an overwhelming force and depend upon
-weight of numbers and extremely small districts to ensure success. The possibilities
•of this system are soon reached, owing to the prohibitive expense. The other system
is to adopt specialization, to use fewer but more highly trained men, to co-ordinate
-.their activities by organization and discipline and to assist them with every form of
Fig. 2 Steel lookout tower on a Dominion forest reserve in Saskatchewan
mechanical appliance that will multiply their individual effectiveness. Among these
appliances modern means of intercommunication are of basic importance, and in no
respect is this more evident than in specialized means of Detection.
The function of Detection in a specialized staff is performed by units entirely
distinct from the rest of the force. The nature of their duties is such that they can
rarely perform any other duties even as a secondary function, and only in a very
imperfect way can other units perform the function of Detection on a secondary
basis. These units, charged specifically with the duty of detecting and locating fires,
are known as " lookout men " and hundreds of them are employed in specialized forest
SPECIALIZED FOREST PROTECTION 7
protection forces in the United States. They are a most picturesque unit, perform-
ing a little-known but valuable service under most unusual and often trying con-
ditions.
For the most part lookout stations are established on the tops of prominent
mountain peaks; mount Hood in the Cascades, mount Fairview in the Rockies, even
the active volcano, Lassen peak, in northern California, and scores of other mountains
throughout the Western States are used for lookout purposes. Several have also
been established in British Columbia by both the Dominion and provincial forest
services. In the Eastern States, notably in New England, a very extensive develop-
ment of the lookout system has taken place. Practically the entire timbered area of
these states, and large parts of many others as far west as Minnesota, are watched b,"
permanent lookout men throughout the fire season. The location and character of
the lookout stations is determined by the nature of the topography. If suitable
sharp-topped peaks are not available towers must be erected. Lookout towers as high
as 150 ft. have been built but ordinarily the standard steel towers which run from
30 to 80 ft. high are satisfactory.
Satisfactory lookout service in a specialized organization demands the continuous
presence of the lookout man at his station throughout the daylight hours ssven days
in the week. This can be accomplished only by making the lookout station and
dwelling-house one and the same. Accordingly a type of building has been especially
designed for this work which is so arranged that no matter where the lookout may
be while in the station he can always have a clear and unobstructed view of the
entire area for which he is responsible. His duty, therefore, is easily defined. It is
to remain at his station continuously throughout the day and maintain a constant
watch over the area within his range of vision, noting all indications of fire, determin-
ing 1heir location ,and reporting immediately to the proper unit of the control force.
For the purpose of aiding him to fulfil his function he is provided with 'certain
mechanical devices. These include tinted glasses to protect his eyes and aid him to
distinguish faint smoke at long range, field-glasses with which to examine suspicious-
looking smudges, a special form of lookout map correctly oriented, a fire locator (or
alidade) for determining the bearing of a smoke, and finally a telephone or other
means of communication by which he may report without delay. Rapid means of
communication are fundamental to successful lookout service. For this purpose the
forest telephone is universally preferred', but other means are sometimes used for
reasons of expediency and are nearly always maintained in order to guard against
temporary isolation of the station should the telephone line be broken.
Wherever a region is fully covered by lookout stations, the precise location of a
fire within a distance of a fraction of a mile may be quickly secured by the simple
process of intersecting from two or more stations. Where the fire is visible from
only one station, other methods of location, slightly less exact, have been devised.
Many difficulties in the establishment and maintenance of dwellings on the high peaks
of the western mountains have been encountered and many ingenious devices resorted
to in overcoming them which it is beyond the scope of this manual to discuss. Also,
it is impossible to discuss the human factor in lookout service which is in itself an
element of much importance.
Section 8 — Suppression of Forest Fires
A fire having been discovered and reported by the lookout man, the third element
of the specialized staff is brought into action. This is the unit whose main function
is Suppression. The title " smoke chaser " applied to this unit adequately indicates
the nature of the service. The " smoke chaser " corresponds to the fireman of a
city fire brigade. His duty is to remain within call of his telephone bell or other
communicating apparatus and upon being advised of the location of a fire to proceed
to it by the shortest route in the least possible time and to extinguish it. Here,
8 METHODS OF COMMUNICATION FOR FOREST PROTECTION
again, minutes count and every possible measure is taken to see that none are lost.
If he travels on foot, his pack is ready to be instantly shouldered. After careful
study and experiment a " smoke chaser's " pack, containing all essentials for three
days and the tools needed1 for fighting a fire, has been devised to weigh only 21
pounds. If he can use a horse, it stands ready saddled and bridled; if he travels by
power boat, it floats at his dock fully equipped. His only duty is to leave instantly,
get to the fire in the least possible time, and d"o everything in his power to put it
under control.
Section 9 — Supervision of Protection Forces
The " smoke chaser," however, is only the first or skirmish line of defence.
Back of him stands the whole organized control force, the entire man-power of the
community where this system has been most highly developed. This brings up the
fourth function, that of Supervision. For the successful operation of a specialized
protective force it is essential that the function of Supervision be performed by a
permanent staff. In order to provide year-long employment economically this staff
must necessarily be incorporated in the organization which is concerned1 with the
woods operations. Private owners can incorporate it in their logging crews; govern-
ments, in the scaling or inspection staff. This is a particularly easy problem in
Canada where logging is confined almost exclusively to the winter season and fire-
ranging almost wholly to the season when logging ceases.
Keeping in mind the military analogy already alluded to, it will be evident that
the supervising staff is nothing more or less than a skeleton organization composed
wholly of officers, which organization can be rounded into a complete defensive unit
by calling upon a large body of assistants of various degrees of training, according
to the necessities of the season. In a region where anything in the nature of
permanent settlement is found, this training may, indeed, be carried to considerable
lengths and the efficiency of the force greatly enhanced.
It will be realized, however, in studying the details of forest protection work
that it divides rather distinctly into two general classes. There is on the one hand
the more strictly administrative duties which fall to the various supervising officers.
These include the day-by-day supervision of the work of prevention and detection
forces ; the inspection of field conditions ; study of fire conditions and labour supply ;
preparation and revision of mobilization schemes; the supply of provisions to field
forces ; direction of construction on improvement projects and various other activities
not concerned with the actual process of fighting fires, but either preventive in
character or in the nature of preparation for fighting fires that are anticipated.
On the other hand there is the actual forest fire-fighting, mostly on a small scale
in a smoothly running organization but sometimes on a very large scale and with
crews of considerable size. This, too, will as a rule be under the direction of the
same supervisory officer, although in some cases the actual executive work on the
fire-line is placed in the hands of a fire-line foreman while the supervisory officers
devote their attention to co-ordinating the various auxiliary services and determining
the general strategy of the fire-control operations. Here is seen a distinct develop-
ment of staff and line functions as will be hereinafter explained.
Section 10 — Duties of Supervising Officers
It will be readily apparent that the duties and responsibilities of the supervisory
officer in a specialized staff are much more extensive and call for a far more careful
training than those of any grade of employee in a non-specialized force, or even in
the other units of his own organization. He must be more carefully selected, more
highly trained, and, naturally, better paid. His duties in connection with fire preven-
tion are as follows: —
SPECIALIZED FOREST PROTECTION 9
v
1 — DIRECTOR OF PERMANENT FORCES
The maintenance of supervisory control over the entire prevention, detection, and
suppression staff regularly employed in his district is of first importance to the super-
visory officer.
To do this it is essential that he be able to maintain communication with all units
of this staff. This is accomplished by the proper planning of the permanent lines of
communication witihin the district and the skilful use of the portable and emergency
equipment described in this manual.
2 — MOBILIZATION OF SUPPRESSION FORCES
The supervising officer must organize and direct the mobilization of all the forces
needed to form the main and supporting lines of defence in fire suppression. While the
aim of specialized forest protection is always to handle all fires in the incipient stage
this ideal cannot always be maintained, and through delays in detection or reporting,
faulty location or other failures, some fires will prove too formidable for the "smoke
chaser" alone. There are few forest regions even in the more remote parts of Canada's
commercial timber-belt where there is not some form of local settlement. Where agri-
cultural settlers are not found there are still logging camps, miners, construction crews,
or perhaps surveyors, tourists, summer residents, hunters, etc. The communication
system must be planned to put the supervising officer in direct touch with all these
sources of labour and he must organize this labour so that in ease of emergency it may
be called upon for assistance with a reasonable certainty of an immediate and effective
response. This has been accomplished in several ways but probably the most successful
has been through the organization of volunteer fire companies, organized with all the
necessary officers and bound by agreement to report on call at designated points. Many
factors and local conditions necessarily cause wide variations in the possibilities of
developing these forces for use in fire emergencies.
In the more highly perfected organizations it is possible to distinguish three lines
of defence or classes of forces behind the "smoke chaser." These may be called: —
(a) Main line forces, which are as .a rule made up of all the available employees of
the timber-owner;
(&) Supports, which consist of local residents usually scattered through or on the
immediate borders of the forest who are under definite contract to perform certain
specified emergency fire duties; and
(c) The Reserves, which may consist of organized volunteer fire companies as out-
lined above or may be simply an available labour supply at some adjacent centre where
arrangements for securing men have been made through labour agencies or other
means.
Whatever is the form and composition of the Supports and Reserves, the mobiliza-
tion, equipment, and transportation of these forces to the fire-lime must be (handled by
the 'supervisory officer and his staff. Fire plans, which are an essential feature of
specialized fire protection, detail the means for accomplishing this concentration, but
the expeditious carrying out of the features of such a plan is largely dependent upon
the system of communication.
3 — MAINTENANCE AND DIRECTION OF SUPPRESSION FORCES
Finally, the supervisory officer must provide for the maintenance of his forces on
the fire-line and the direction of the work of suppression by these forces. In this, his
problems differ, from that of the military officer in no material aspect except the merely
rudimentary development of his medical service -and the absence from his transportation
columns of anything corresponding to the enormous quantity of ammunition required
by modern troops. A complete discussion of this phase of the function of supervision
10 METHODS OF COMMUNICATION FOR FOREST PROTECTION ,
might constitute the subject matter of a manual of forest protection and is beyond the
scope of a manual on communication alone, but the main divisions of it may be very
briefly considered. In doing so, however, it is necessary to recollect that although the
object of all fire-protection forces is principally to prevent fires, nevertheless the supreme
test will come in the actual handling of a dangerous forest fire and all organization
must be based upon preparation for this contingency. This, of necessity, involves a
somewhat elaborate organization which must be provided though it may never in prac-
tice be utilized for the purpose intended. From this it does not necessarily follow that
a staff is held idle merely awaiting emergencies that no effort is spared to avoid. On
the contrary, the skill of the organizer is shown by the way the necessary staff is
secured for emergency work without continuous maintenance. This force as already
indicated is divided into line and staff according to the nature of its duties.
Section 11 — Duties of Suppression Staff Officers
These are five in number and give rise to five separate departments, but it is seldom,
even in a very dangerous region, that all are separately organized.
1 — TRANSPORT
The transportation problem becomes important only when relatively large fires
must be fought at a considerable distance from a base of supplies. Its difficulties
arise more from the poor quality of the lines of communication over which trans-
portation takes place than from any other factor. Crews seldom exceed 100 men
though more than 1,000 have at times been engaged in one locality. Distances are
sometimes considerable, frequently 25 miles beyond the railways, sometimes more
than 100 miles. Wagons, boats, or pack-horses are the usual equipment employed.
Sometimes motor-cars may be used but on the other hand1 it is sometimes necessary
to pack supplies on men's backs. When, as is nearly always the case in the western
forests, pack-horses are the only feasible means of transport, the maintenance of a
hundred men on a fire-line is quite as difficult a transport problem as is the main-
tenance of 2,000 or 3,000 men in a country where modern motor-trucks may be
employed.
The transport service in a specialized force is seldom under the direct charge
of the supervisory officer having immediate charge of the smallest fire-protection
district or unit of area. As a rule ten or more such districts are combined under an
officer of higher rank and. the transport service for the entire group is handled from
a central headquarters. Where necessary a chief transport officer, genemlly called
the " packmaster," is employed for this purpose.
A very important element of transportation is the condition of the lines of com-
munication, such as roads and trails. It must be the constant aim of a forest-
protection force to improve these lines at every possible opportunity. In the accom-
pF.shment of this an intercommunicating system is of the highest importance. Its
value arises from the fact that in scarcely any forest region is the fire season continu-
ous, but owing to rains there are periods of greater or less length when no fire is
likely to occur. The efficient organization will plan to use the fire-protection staff
during such periods for the extension or improvement of lines of communication.
This is accomplished by preparing in advance careful plans for necessary improve-
ments to roads, trails, or other permanent works, distributing the work as much as
possible to all districts. Immediately on the occurrence of a heavy "rain, the fire-
control force is swung on to improvement work through the medium of the inter-
communication system and is kept employed on this work at the discretion of the
supervising officer until conditions again require a return to fire-control duties. The
SPECIALIZED FOREST PROTECTION 11
amount of work that may be accomplished in this way depends on the seasonal condi-
tions but it rarely happens that a fairly considerable total does not result from
careful preliminary preparation and skilful use of opportunity and of the means
of communication available.
2 — COMMISSARY
The bulk of the material handled by the transport service to fire-fighting crews is
food'. This is supplied in the most successfully organized forest districts through a
central depot which distributes to a group of fire-control districts, generally the same
group as is handled by a single transport officer.
The officer in charge of the commissary is called the " quartermaster " and, in
fact, very often combines the duties ,of quartermaster with those of packmaster. He
arranges for the delivery of the necessary food, tools, and miscellaneous camp
supplies, such as tobacco, so<eks, etc., from the main supply points in the nearest
towns to one or more base stations from which they are distributed to the fire-fighting
crews as required. The cooks at the various camps make requisition upon him for
supplies either directly by telephone or other line of rapid communication, or
indirectly by message to the nearest telephone station. The extreme uncertainty of
the extent or duration of this class of work constitutes the principal element of
difficulty for the quartermaster, and this he is enabled to minimize by being in
constant direct communication with each camp.
3 — FINANCE AND ACCOUNTING
The payment of fire-fighters must be handled promptly, especially where large
crews of a floating class of labour are involved. Also, an efficient organization will
want to maintain an accurate record of its expenditure and an adequate cost-
accounting system. This is generally handled by a paymaster who disburses for a
group of fire-control districts, often including two or more groups of the size handled
by a single quartermaster or packmaster. The intercommunicating system expedites
the work of the paymaster by enabling him to get advance information in regard to
the men coming out and the amount of disbursement he must be prepared to
make each day. This is often of great importance in regions where banking facili-
ties are limited. On the fire-line he is represented by the timekeeper who, however,
generally has other duties to perform as well.
4 — INTERCOMMUNICATION AND RECONNAISSANCE
As has already been indicated it is of vital importance to the efficient operation
of each of the several departments of the fire-control staff that constant communi-
cation be maintained between the fire-fighting crew and the various headquarters in
the rear of the fire-line.
It is also of much importance on a large fire that the officer in charge be kept
constantly informed of the progress of the fire in all its parts and of the success or
failure of the various control measures undertaken by the forces combating it. This, of
course, assumes that a relatively large fire is being subdued. Small fires may be readily
observed by the officer in charge and no special organization for securing information
is needed. On large fires, however, it is frequently found desirable to employ a scout
or intelligence officer. The duty of this member of the force is to keep the chief of the
fire-fighting force informed of all important features of the work of fire control and of
the progress of the fire itself where not yet under control. He is also, as a rule, charged
with establishing and maintaining communication with the headquarters in the
rear. Now, it rarely happens that a fire camp is located on a permanent telephone
line. If, therefore, it is considered necessary that the camp be equipped for direct
communication it becomes the duty of this officer to provide telephone connection or
12 METHODS OF COMMUNICATION FOR FOREST PROTECTION
establish communication by some other direct means. The methods by which this may
be done are explained in this manual in Chapter X of Part II and in Part III. It is
desirable here only to indicate the organization by which it is effected. Naturally, such
communication will be required only in exceptional cases. A camp that will be occupied
for only a few days at the most and that would need to send only a very few messages
would handle them by messenger. But where a large camp may be occupied for a period
of weeks, perhaps, and is only one of several engaged in the control of a single large
fire, then it may be extremely important to establish direct connection. It is the same
problem that faces the military officer who must decide whether to ©end an order by
messenger or have it transmitted by signal. The circumstances in each case and
knowledge of the possibilities of all means available must be the guide in the action
taken.
5 — FIRE SUPPRESSION STRATEGY
The strategy of fire-fighting as distinct from tactics has the same significance as in
military operations, that is, it comprises all those broader elements of the problem such
as existing conditions of fire, topography, season, forest, forces available, and other
factors which taken together determine in a broad way the general method of attack.
Unfortunately there is not -available in fire-fighting records any body of detailed reports
of fire-fighting operations with the reasons therefor and the results attained, such as
exist in military history, and lacking this essential data fire-fighting strategy still
remains in a condition of very rudimentary development as a practical art. In actual
practice it is necessary to rely entirely upon the individual capacity of some member
of the force who has himself only his own individual experience to depend upon. Non-
specialized forces assume this knowledge of all their members. Specialized forces
undertake to bring to bear on this important line of work a more extensive experience
by making available for study by the permanent staff such detailed reports of fire-fight-
ing strategical operations as can be secured and by relieving some of the staff officers of
most of the usual details of forest protection work so that they may give special atten-
tion to this important phase.
Section 12 — Duties of Suppression Line Officers
1 — CAMP MANAGEMENT
Unlike, military camps, fire camps are extremely simple/ It is very seldom that
such camps are large enough or remain in one place long enough to require special
sanitary precautions or highly specialized organization. Provision for safety in loca-
tion is necessary but usually is easily secured. The same is truie of provision for
medical service. Injuries, sometimes fatal, are not uncommon in fighting fires and yet,
on the whole, they are not sufficiently numerous to require any special organization.
There is, therefore, in a specialized fire-protection staff nothing that corresponds to the
medical corps or sanitary corps of an army. All responsibilities of this nature as a rule
fall upon one of the line officers, such as the camp foreman. The greatest advance has
probably been made by those organizations which maintain at their base supply stations
a number of special fire camp first-aid kits, which are distributed by the quartermaster
as needed, and handled by the timekeeper or the camp foreman in the field.
2 — FIRE SUPPRESSION TACTICS
The tactics of fire-fighting include all those specific measures of control that are
employed in the immediate vicinity of the fine. As a specific illustration, a decision to
divide the crew and begin the attack on the fire on both flanks at once rather than to
endeavour to combat the head is a strategical one, but a decision as to whether to cut a
trench near the edge of the fire or to use a trail existing at some distance from the
. SPECIALIZED FOREST PROTECTION 13
edge or to make no guard-lime at all but try to beat out the fire or to extinguish it with
water, is a tactical one. Fire-fighting tactics have advanced much further in organized
development than has strategy. A considerable number of methods are known and
much has been dome toward improving these methods. Particularly is this the case in
methods for using water in fighting forest fires. Theoretically water is the ideal
material to use for fire extinguishment 'but the practical difficulties of getting the
material to the point of use are very great in all but a few very limited regions. As
might be anticipated, it is only those highly perfected organizations which have solved
the problems of preparedness and strategy that are able to advance with real success
beyond the simple fire-fighting tactics to the employment of more elaborate methods
involving the use of water, particularly the employment of gasolene pumps.
Section 13 — Value of Communication System in Field Operation
The value of a highly developed system of communication lies in making
possible the rapid concentration of adequate control forces on the fire-line and in
their successful maintenance. It has little direct bearing on the actual conduct of
the fight. Indeed, an unspecialized force with no rapid means of communication may
use just as efficient tactics as the most highly specialized force with the most improved
system of intercommunication. Where it will fail, however, will be in the early
discovery and in the rapid concentration of adequate forces in such fires as occur and
in the ability to handle and maintain large forces in regions of difficult accessibility.
The result is seen in comparing the records of specialized with non-specialized forces.
Wherever conditions are at all comparable, a specialized staff will secure protection
at a mere fraction of the cost of equal protection by an untrained non-specialized
staff. Moreover, the specialized force will be able to secure adjustment of expendi-
ture according to the character of the season from year to year, or even from period
to period during any one season, which an unspecialized force cannot do with any
real success. Finally, the specialized force will weather the periodical unfavourable
seasons with success, both because it expands automatically according to the danger
and because it strikes quickly and places fires under control without delay. It cannot
be taken by surprise but detects and locates fires with certainty and precision while
they are still in an easily controllable stage. Its record will show few or no large
fires in a dangerous season and a low average of acreage per fire, while the record
of the non-specialized force in a dangerous season will always show a break-down
more or less complete and a high percentage of fires that get beyond all control and
burn themselves out or until extinguished by rain. These periodic break-downs are
of much greater importance in judging the efficiency of fire-protective organizations
than is generally admitted, since it not infrequently happens that the destruction
that occurs in a single disastrous season more than offsets the protection afforded
during a very long series of favourable years. On the whole, in most timbered
regions where advancing settlement, railways, lumbering operations, and various
other developments have radically changed the forest fire situation for the worse, no
organization for forest protection can be considered efficient unless it has made
adequate provision for automatically' expanding during exceptionally dangerous sea-
sons, so that it can at all times keep the situation well in hand. The real test of
success is not control of fires during normal seasons but control during the periodic
abnormal season without the necessity for keeping up at all times a large and expen-
sive organization that serves 'no other useful purpose.
CHAPTER II
METHODS OF CONVEYING INFORMATION TO A DISTANCE
Section 14 — Variety of Methods Available
Perhaps the oldest and simplest means by which information may be conveyed
from one point to another is by messenger. The most modern and technically com-
plex is the wireless telegraph and telephone. Between these two extremes lies the
whole knowledge and experience of man in the solution of this problem. This has
always been a problem of paramount importance to military forces so that we find
in military literature the most complete and exact records of the various methods by
which it has been solved. These methods are of the most varied character but may
all be divided into two principal classes : the Visual Signals which are received through
the sense of sight and the Audible Signals received through the sense of hearing. In
order to show the possibilities for selecting methods adapted to particular circum-
stances, it is of interest to note briefly the characteristics of the more important types
of signals and other means of conveying intelligence to a distance.
The use of carrier pigeons, so extensively employed in military and nava.l opera-
tions, has, so far as the author is aware, never been attempted in forest protection.
There seems to be no reason, however, why carrier pigeons could not be very success-
fully employed in this work.
Section 15 — Types of Visual Signals
1 — WIGWAG SIGNALS
This system consists in forming the symbols of the telegraphic code by moving
various objects in certain ways with reference to some fixed object. A flag swung to
the left or to the right, for instance, the person swinging it acting as the point of
reference is a common method of sending wigwag signals. Torches, lanterns, or in
fact any object visible at a distance may be similarly employed. Over great distances
the beam of an electric searchlight thrown vertically can be used to send messages by
wigwag.
2— SEMAPHORE SIGNALS
By varying the positions of objects of the same shape with reference to a fixed
object, it is possible to form symbols that represent the letters of the alphabet. Thus,
the two arms may be so held with reference to the body and to each other as to form
all the different symbols needed to send the full alphabet. To extend the range of
visibility small flags are held in the hands. Special semaphore machines with movable
arms of large size are also used. Within a limited range this system has many
advantages, particularly that of speed.
3 — CODE SIGNALS
Without attempting to send alphabetical symbols it is possible to send pre-
arranged messages by the use of objects of different colours or shapes or by a com-
bination of both, using one or more of them to represent each code message. Flags
of different colours and designs are most commonly employed for this purpose and the
system is used for communication by ships at sea and for such purposes as displaying
storm warnings or other weather signals. Of course, similar flags of distinctive
colour or design may also be used to represent the letters of the alphabet and words
spelled out in full.
4 — CHRONOSEMIC SIGNALS
In all the foregoing systems the time of display of the signal does not form an
essential part of the method. Several systems are in use, however, in which time is
14
METHODS OF CONVEYING INFORMATION 15
an important element. In one of these, the chronosemic method, the basis is the time
interval that elapses between two displays of the same object. To form the letters of
the alphabet by the International Horse Code it is only necessary to be able to make
two symbols, a dot and a dash. This may be done by allowing a short time interval
between two displays of a flag, for instance, to stand for a dot and a longer interval
to stand for a dash. It is a method that is valuable, however, only when using for
display something that cannot be easily controlled as to the length of time it remains
visible. Such, for instance, are rockets or bombs of only one colour. The interval
between displays of these devices may be easily controlled and varied but the duration
of the display itself cannot be controlled. Smoke puffs or flashes from a hand mirror
are somewhat similar but any visible object may be used if desired.
5 — FLASH SIGNALS
Instead of forming the dot and dash of the code letters by the time interval
between displays of an object, it is readily possible to form them by the time interval
during which the object is visible. This, of course, pre-supposes that the duration of
visibility is entirely under control. Although a great many different objects may be
used for this purpose, the actual application of the method is mostly made through the
medium of sun flashes from mirrors, or flashes from different forms of signal lamps.
The apparatus used being provided with suitable devices for controlling the duration
of the flash, it becomes readily possible to form the code letters by making a short
flash for a dot and a long flash for a dash. Other objects less frequently used are flags
and disks.
6 — ELECTRO-TELEGRAPHIC SIGNALS
The ordinary telegraph may be easily equipped so as to furnish a written or
printed message. This might, perhaps, be included under visual signals though this
term is generally confined to non-electrical means of communication cnly. Similarly,
the mirror galvanometer used in submarine electric telegraphy is also a form of visual
signal.
7 — SHAPE AND COLOUR SIGNALS
In addition to the foregoing there is a numerous and important class of signals in
which the operator depends upon using two or three objects of easily distinguishable
shape, or two or three lights of different colours, to form by their arrangement all the
letters of the telegraphic code. For the two-symbol codes, such as the International
Morse Code, only two shapes or colours are required. Each represents an element
of the code letters and by displaying them simultaneously in the proper relation to
each other, or separately in the proper sequence, the entire alphabet may be readily
formed. Thus, for day signals a ball may represent a dot, a cone may stand for a
dash, and with combinations of these two shapes displayed together all the letters of
the code may be formed. At night several methods are employed using coloured
lights, rockets, coloured balls, or bombs, and coloured lanterns. One method, known
as the Ardois lantern system, employs an ingenious arrangement of electric lanterns
which can be operated by a special switchboard from a distance and at considerable
speed. The range over which such signals may be seen, however, is comparatively
short.
Section 16— Types of Audible Signals
Audible signals are not of such a varied character as are the visual signals. They
are of two main classes : non-electrical and electrical, and may be tabulated as
follows : — •
Non-electrical, (1) Detonations — revolver or rifle shots, dynamite explosions, (2)
whistle or trumpet blasts, (3) bells.
Electrical, (1) Electric telegraph or telephone with wires, (2) electric telegraph
or telephone without wires.
16 METHODS OF COMMUNICATION FOR FOREST PROTECTION
The range of non-electrical audible signals is extremely limited, unless detonations
or whistles of immense power are employed. Further, they are of limited application
because relatively slow. 'Nevertheless, such signals are very widely used for the
purpose of conveying code messages where only a few very simple messages need to 'be
employed. Such, for instance, is the employment of whistles and bells on boats, trains,
and steam-logging operations, of detonating torpedoes on railways, and of whistle and
trumpet blasts in the directing of military manoeuvres.
Electrical means of communication are the most modern and most efficient of all
the methods employed. Thus far, of the wireless methods, only the wireless telegraph
has been brought to a high state of perfection. Of the methods of transmitting intelli-
gence electrically over wires, three principal types may be recognized as follows : —
(1) Transmission of the telegraphic code by the common type of telegraph key,
relay, and sounder.
(2) Transmission of the telegraphic code by the buzzer system^ using a telephone
receiver as the sound-receiving apparatus.
(3) Transmission of the human voice by the telephone.
*•
The first has maximum range and reliability of equipment but requires a rather
high degree of electrical insulation in the connecting lines and special training of the
operators. Where a high degree of accuracy in the message transmitted is required,
it is the most rapid of the electrical methods of communication, exceeding in this
respect even the telephone. On the other hand, it offers little or no chance for secrecy
of messages sent.
The second has a limited range but certain advantages in operating over lines of
poor electrical insulation. The apparatus is comparatively simple but special training
is still a requisite for operation.
The third employs a more complicated apparatus but one whose mechanical
development has reached a very high degree of perfection. It has the immense
advantage of requiring no training for its successful operation and of being under
certain conditions the most rapid of all means by which information may be trans-
mitted. It requires a higher degree of electrical insulation than the second method
and has not the range of the first, but has been shown to have sufficient range for all
necessary purposes of forest protection. Further, it is the only practicable apparatus
by means of which the sender and receiver of the message can communicate directly
with each other without the interposition of a third party.
All the foregoing methods involve the use of wires connecting the points with
which communication is desired. Only at points where actual physical connection to
these wires can be made is it possible to send or receive messages by these systems.
A considerable investment in construction and a continuous charge for maintenance
is, therefore, involved in the use of any one of the systems. On the other hand, the
apparatus required for making connection to the wires when strung and for establish-
ing communication with stations is extremely simple and easily portable in all cases.
The wireless systems of communication, while offering many theoretical advan-
tages, particularly through dispensing with the use of wires, have not, however, been
developed to the point where they are to be considered as serious competitors of the
present system of telephones with wires. Although improvements are constantly being
made in this field of communicaiton, the requirements of extreme portability are, as
yet, met more effectively by the equipment at present in use. The development of the
wireless telephone during the war has 'been such that its employment as a supple-
mentary equipment must be given serious consideration. To a certain extent the use
of the wireless telegraph -as a temporary or as a supplementary equipment may also
be advantageous, but the necessity of having trained operators is a serious disad-
S vantage of this system, f^ne ultimate development of the wireless telephone is of the
utmost interest to all who are interested in forest protection as it promises to overcome,
;\ when perfected, nearly all of the obstacles at present met with in the establishment
\ of cheap, reliable, and quick communication in forested regions.
CHAPTER III
ADAPTING COMMUNICATION METHODS TO SPECIALIZED FOREST
PROTECTION
Section 17— Speed and Certainty in Communication Essential
The units that compose a specialized force have already been described. Prac-
tically all of these units must be equipped to communicate with each other in order
to operate efficiently. Some of them are wholly useless without rapid and reliable
means of communication at all times; on the other hand the more -nearly perfect
the system of intercommunication between all the various units can be made, the
more efficient will be the protection under given conditions. Centralization of direc-
tion is only workable when the central directing intelligence is in constant touch
with the many scattered units of the field force. How far centralization can be carried
advantageously will perhaps be a matter for discussion, but there can be no question
that any change from a method that reposes all responsibility in the lowest member
of the staff must be accompanied by development of means for keeping the field units
ill constant direct communication with the supervising staff. Also, any specializa-
tion of function as, for instance, the employment of permanent lookout men to detect
fires, necessarily involves the provision of means whereby these men can quickly and
surely transmit to the suppression forces information with regard to fires located.
This must -not necessitate the lookout man leaving his station and, to be more efficient
than the old style patrol method, it is essential that the lookout men transmit the news
of all fires located in less time, in all cases, than the average time for detection and
location required by the patrol. 'Speed and certainty in the method employed are,
therefore, fundamental necessities.
Section 18 — Method must be Adapted to Conditions of Use
It will be apparent from the discussion of the methods of transmitting intelligence
that there is a very wide range in the capabilities of the many forms of signals
employed and that a choice of type for a given use must be governed by the require-
ments of that use and the characteristics of the signalling methods themselves. The
latter are of the most varied description. Some can be used only in daylight, others
only in full sunlight, while many can be employed only at night. Atmospheric condi-
tions have a considerable influence on the range of all types of non-electrical visual
signals, on some audible signals, and also to a less extent on electrical systems.
Possible ranges, with different methods under given conditions, vary from a few
hundred yards up to hundreds of miles. Possible speed of transmission of given
messages under given conditions likewise shows a wide range. Various degrees of
skill and training in the operation of different systems are required and the ease with
which skill is acquired varies. The apparatus required shows great diversity in cost,
complexity, portability, ease of manipulation, and ability to stand rough usage. The
variations in cost and difficulties of installation and maintenance are equally wide.
On the other hand, there is to be considered the requirements of the service
demanded by a forest-protection staff. In order that this may be understood it is
well to have clearly in mind the principal units of a specialized staff.
Section 19 — Control Units Requiring Intercommunication Facilities
From the location, function, and methods of operation of these various units
it is possible to arrive at a general idea of their requirements in the way of means
of communication. The principal units involved are: —
79211—2
17
18 METHODS OF COMMUNICATION FOR FOREST PROTECTION
1 — PATROLMEN. — Moving units, mainly preventive in function. They are
employed only where fires of human origin are likely to occur in considerable numbers,
such as around new settlements where they issue brush-burning permits and super-
vise burning operations. Along railways patrolmen combine detection with suppres-
sion, and through examination of spark arresters, etc., help with preventive measures.
2 — LOOKOUT MEN. — Stationary units, whose only function of importance is detec-
tion. They are located on commanding peaks or other elevated stations from which
a great scope of country can be observed.
3 — " SMOKE CHASERS ". — Largely stationary units whose principal duty is sup-
pression. They may be stationed with the lookout men or at points near the bulk of
the timber to be guarded, if the lookout station is not itself in a readily accessible and
central location.
4 — DISTRICT RANGER. — The supervisory officer who directs the work of the preceding
units within a definite area or forest district and also has administrative control of
the main line of defence when larger fires must be controlled, and of the supports and
reserves. His chief executive assistants are: —
(a) Intelligence Officer or Scout. — His duties are to secure information in regard
to the behaviour of fires and the progress of control work;
(&) Packmaster and Quartermaster. — As a rule these services will be directed
irom a central headquarters having control over a large number of ranger districts,
but in cases where the system of communication is not fully developed it is sometimes
necessary to establish separate supply departments for each of the smaller districts;
(c) F.ire Bosses. — In the more complete organizations each individual large fire
is handled by a special fire boss under whom are the various camp foremen in charge
of line crews. In many cases, however, the district ranger is himself the fire boss.
5 — SUPERVISOR. — The officer having administrative control of a group of adjacent
forest districts. His chief executive officers are the district rangers in charge of
fire control aiid the following chiefs of special services: —
(a) Paymaster. — The disbursing officer;
(&) Paymasters. — One or more officers in charge of transportation;
(c) Quartermasters. — One or more officers in charge of commissary.
ADAPTING COMMUNICATION METHODS TO FOREST PROTECTION
19
Section 20 — Communication Requirements of Control Units
The normal communication requirements of these units are as follows: —
,
Distance
Unit
Communicates with
Common
range of
distance
Average
distance
Class of Message
Supervisor
District Ranger
Miles
0 to 100
Miles
25
Long, intricate.
Packm aster (not at head-
quarters)
25 to 100
40
Generally brief.
Quartermaster (not at
headquarters)
25 to 100
40
Generally brief but
occasionally long and
very intricate.
Lookout Man
5 to 100
30
Sometimes long and very
intricate but generally
short and precise.
District Ranger
Lookout Man
1 to 30
10
Same as above.
"Smoke Chaser"
1 to 30
10
Same as above.
Patrolman
5 to 30
10
Generally long but rela-
tively infrequent.
Supervisor
1 to 100
25
Long intricate
Supports
1 to 50
10
Long and intricate or
short and concise ac-
cording to perfection of
organization and dis-
cipline.
Reserves
1 to 50
25
Same as above.
Camp Foreman
2 to 15
5
Very long and intricate'
Scout
2 to 20
10
Very long and intricate.
Lookout Man
Supervisor or District
Ranger
1 to 100
30 or 40
Sometimes long and in-
tricate but generally
short and precise.
"Smoke Chaser"
0 to 20
10
Same as above.
'Smoke Chaser"
District Ranger or Look-
out Man
1 to 30
10
Generally short and pre-
cise.
Scout
Lookout Man
2 to 30
10
Short and precise only
when long intricate
messages are not feas-
ible.
Camp Foreman
0 to 5
2
Short and precise.
Quartermaster and 'Pack-
District Assistant on afire
5 to 100
30
Often long and intricate.
master.
Camp Foreman . . :
Scout
0 to 5
2
Generally short but may
be very long on occa-
sion.
Fire-line Ciew
0 to 1
i
Short, precise or long
and very detailed.
District Ranger
2 to 15
5
Long and intricate.
Patrolman
District Ranger
5 to 30
10
Short and precise or long
and very detailed.
79211—
20 METHODS OF COMMUNICATION FOR FOREST PROTECTION
An analysis of these requirements reveals the following facts: —
(1) Most of the messages which it is necessary to transmit are long and involved
in character.
(2) The longer and more intricate messages generally have to be transmitted
over great distances but in a relatively few cases over v'ery short distances.
(3) Where relatively short distances are involved there are generally two classes
of messages to be transmitted.
(4) The longer distances vary on an average from 10 to 40 miles, with 100 miles
as a usual maximum..
(5) The shorter distances vary on an average from one-eighth of a mile to 5
miles, with 15 miles as a maximum.
Section 21 — Superiority of the Telephone Evident
A study of the kind of messages that must be ser.t, the men who send them, and
the ranges over which the communication system must operate leads inevitably to
the conclusion that only the telephone comes near enough to meeting all requirements
to form the basis of the system. It is among the most rapid of the methods- of com-
munication and, therefore, well adapted to long intricate messages; it requires no
skill to operate, will give more service at less cost, considering installation, operation,
and maintenance, than any other system, operates efficiently within the range limits
desired, may be connected with at any place along the wires with easily portable
equipment and, as will be shown, may be quickly and cheaply extended within
adequate limits to nev* locations for temporary use during emergencies.
Its advantage over the telegraph is largely iri requiring no training to operate.
Over wireless methods it has the same advantage while additional objections to wire-
less are the relative non -portability of the equipment for sending purposes, the com-
plexity of the apparatus, and the limitations on the establishment of sufficient
stations due to cost. The telephone, therefore, must form the basis of our entire
system of intercommunication, and as a result of this decision equipment and methods
of construction particularly adapted to forest-protection purposes have been specially
developed and employed until there are now more than 30,000 miles of such lines in
successful operation in the United States and nearly 2,000 miles in Canada.
Section 22 — Auxiliary Methods often Required
The wide acceptance of the telephone for this class of work, however, does not
entirely obviate the necessity for givinlg some consideration to other methods of com-
munication. Several important conditions -must be recognized wherein the telephone
alone does not fully meet all requirements. In this we find another parallel to military
communication for, in spite of the perfection of telephonic communication by army
signal services, several other means of conveying information have been carefully
developed. In forest-protection work various other systems are of considerable value
under the circumstances that will now be explained.
1 — 'COMMUNICATION IN ADVANCE OF TELEPHONE CONSTRUCTION
In equipping a large area of timber-land with telephonic communication it will
nearly always be impracticable to install a complete system in a single season. In fact
for reasons of expediency a considerable period of years may elapse before such a
forest is fully equipped. There arises then an immediate need for some temporary
system of communication which will bridge over the period during which the permanent
system is in process of development. This is a consideration of very great importance
in Canada where specialization in fire protection, with its accompanying construction
ADAPTING COMMUNICATION METHODS TO FOREST PROTECTION 21
of intercommunication systems in the forests, is just beginning. This temporary
equipment must be as inexpensive as possible, because it is merely temporary. It must
be capable of transmitting messages over long distances. Simplicity and ready portabil-
ity of equipment are desirable. It must be fairly easy to operate and be reasonably
certain and reliable.
Among all the various signalling apparatus previously described the heliograph
alone meets these requirements. A heliograph costs, complete, from thirty to sixty-
five dollars, about the cost of a single mile of telephone line. Its range is much
greater than the ordinary maximum distance required in forest work. It is remark-
ably simple in construction and the new forest-protection type is easily carried by a
horse patrolman. Experience has shown that with a few days expert instruction
intelligent rangers can acquire sufficient skill in its use to form the basis for attain-
ing speed by individual practice by themselves. In speed it cannot be compared with
electrical systems and it has the further disadvantage of operating only in full sun-
light. The lack of speed may to some extent be compensated by adopting a code of
pre-arranged messages, as will be later described, and the necessity for full sunlight
is also to a certain degree compensated for by the fact that periodls of dull weather
are very likely to be periods of low fire-danger and, therefore, lessened need for
communication. Heliograph stations must, of course, be visible from each other.
This requirement is the most serious limitation on the use of this instrument, but not
when used on lookout stations where it is most frequently employed.
2 — SUPPLEMENTARY EMERGENCY EQUIPMENT ON LOOKOUTS
A further need for a means of communication other than the telephone is found
in the equipment of permanent lookout stations even after they are connected with
the telephone system. Lookout stations are absolutely dependent upon communica-
tion for the maintenance of their successful operation. No form of electrical com-
munication dependent upon aerial wires is wholly safe against interruption, and such
interruptions- are particularly likely to occur during heavy storms and thunder-showers.
This introduces a dangerous element of uncertainty, especially in the West where a
great many forest fires are started by lightning, and the chances of the lookout being
isolated by the very storm that is causing fires to spring up is a hazard that cannot be
ignored. The most effective way to guard against this is to take a leaf from the book of
military experience and provide auxiliary means of communication for use when the
usual means fail. For this purpose the heliograph is again the most suitable apparatus
and a permanent use for some of the temporary installations may thus be secured.
3 — PATROLMEN
Still another use for supplementary means of communication arises with the patrol-
men. As previously explained, these units are usually assigned to sections of known
fire-risk, such as railways or other important routes of travel. Railway patrolmen
are usually adequately equipped if provided with a portable telephone for connection
to the lines paralleling the right of way, but patrol in a region remote from railway
lines may be isolated from telephone connection. Such patrolmen should, if possible,
be enabled to maintain communication, but the messages they need to send are likely
to be of considerable length. It is, therefore, necessary with each route to weigh the
time required to signal the usual message against the average time needed to reach
the nearest telephone line, and on this comparison make a decision in regard to the
equipment to be furnished. In a region covered by lookout stations it should be quite
easy for such patrolmen to establish communication with a portable heliograph in case
the distance to the telephone line is too great.
22 METHODS OF COMMUNICATION FOR FOREST PROTECTION
4 — SCOUTS
A still further use for auxiliary signals arises1 in the case of the scouting service
on forest fires. It is particularly necessary that men employed on this work be well
acquainted with various means of maintaining communication so that they may be
equal to any emergency. While, normally, communication with large camps will be
established with emergency telephone equipment, many cases will arise, especially
while the telephone system is in course of development, where this will be impracticable.
Two uses for some means of signalling are likely to arise under these circumstances : —
(a) When it is desired to open communication between the camp and the head-
quarters somewhere in the rear. The distance will necessarily be great, otherwise the
telephone would likely be employed. For this use only the heliograph is suitable;
(&) When it is desired to communicate from the heliograph station to the camp
or camps, or from one scout to another, or to a ranger on the fire-line, or across some
impassable barrier. The distance is likely to be short and the message concise. The
equipment must be of the simplest possible character. These requirements are most
readily met by flag signals. Flags, as will be hereinafter explained, may be used to
convey messages either by the wigwag or the semaphore method, the former being,
perhaps, the simpler.
5 — DANGER SIGNALS
Finally, conditions sometimes arise in fighting forest fires, especially in mountain-
ous regions when it is desirable to convey instant warning of danger to the men on
the fire-line. "Many lives have been lost fighting fires and it is the duty of the fire-line
foreman to keep a close watch on the behaviour of fires in dangerous localities and to
be prepared to withdraw his men to a place of safety. Ordinarily this may be done
by messenger, but on the chance that time may be lacking to employ this method it has
been considered necessary by some organizations to adopt a set of danger signals.
These are best made by revolver shots although whistle blasts may be similarly employed.
6 — MISCELLANEOUS FOREST SIGNALS
The need for short distance signals arises very frequently in forest work not only
in forest protection but in many other lines. Communication across impassable
barriers, or between members of survey parties beyond calling distance from each
other, or between members of hunting parties within sound but not sight of game are
conditions under which some form of visual signal would often be extremely useful.
Also in cruising, in some phases of telephone construction (such as pulling wire and
slack) and in various other forest activities where members of crews are out of sight
but within hearing distance, a simple code of audible signals often saves much time
and energy.
PART II
FOREST PROTECTION TELEPHONE LINES
CHAPTER IV
PLANNING THE TELEPHONE 'SYSTEM
Section 23 — Importance of Preliminary Plans
Too much emphasis cannot be placed on the importance of makrng a carefully
drawn plan of the entire system before starting the construction of any part of it.
The longer the line and the greater the number of instruments attached to it, the
greater must be the electrical conductivity of the wire used and the higher the
resistance of the ringer coils in the instruments. An independent pole line 12 to 15
miles in length on which 6 to 8 instruments are to be placed may be constructed of No.
12 gauge galvanized-iron wire and 1,000-ohm ringers may be employed, while if the
same line is to form part of a 100-mile circuit No. 9 gauge wire would be necessary and
2,500-ohm ringers would give the best results. Very long lines might require No. 6
iron wire or it might be necessary to resort to copper which has approximately six
times the electrical conductivity of iron wire of the same gauge. This might radically
alter construction methods. It is of vital importance, therefore, that very careful
consideration be given to all probable future extensions of the telephone system, so
that no type of construction or equipment may be employed which will later prove?
unfitted to form part of a more extensive system than was at first contemplated.
Section 24 — Plans must be based on Definite Area
In planning a system for fire-protection purposes, the basis of all plans must
necessarily be a certain area of timber-land of greater or less extent. This area we
will assume to be contiguous for, although it is sometimes necessary to include non-
contiguous areas in a single protection unit, the variations in condition that may arise
in considering non-contiguous areas are so wide that it is difficult to generalize with
regard to plans for telephone service for such tracts. Usually where government lands
are involved contiguity in adequately sized areas is readily secured. Where private
holdings are involved much success has resulted from the organization of »co-ODerative
timber-protective associations to include the owners of contiguous areas of timber-
land in blocks of sufficient size to warrant the organization of a specialized fire-fighting
staff and the construction of a telephone system. Whatever the ownership conditions,
however, the basis of all fire-protection plans is necessarily a certain area of timber-
land and the more nearly contiguous are all portions of the area, the less per unit of
area is the expense incurred in equipping it with forest telephones.
Section 25 — Primary . Stations Requiring Service
Within or adjacent to the area under protection will be found a greater or less
number of stations that must be joined together by the telephone system. The most
important of these is the headquarters of the supervisor or chief ranger having general
charge of the entire territory. Next come the headquarters of the district ranger and
of his principal administrative assistants. After these the primary lookout stations,
which in a normal season provide for the detection service over the whole tract, must
be connected. When this much of the system is completed the main framework has
23
24
METHO'DS OF COMMUNICATION FOR FOREST PROTECTION
been provided and future extensions need be made only for the purpose of connecting
points of special utility. As a rule, a system which joins all the district ranger head-
quarters and main lookout stations with tihe supervisor's office will, in addition, provide
connection with a large proportion of all other points on the tract that it is desirable
to reach. There may, however, be isolated camps or settlements, secondary lookout
stations, or other strategic points that require short branches from the main circuits.
It is particularly important, however, to note that the central point in any forest-
protection telephone system is the supervisor's headquarters and, therefore, this must
be definitely located at the start in the most suitable place, and the system planned
accordingly.
Before a system can be intelligently planned the following data must be avail-
able in every case: —
(1) Boundaries of tract.
(2) Boundaries of ranger districts.
(3) Location of supervisor's headquarters.
(4) Location of district ranger headquarters.
(5) Location of primary road and trail system.
(6) Location of primary lookout stations.
(7) Location of existing telephone lines on or near the tract.
As many other strategic points as possible should also be determined.
Section 26 — External versus Internal Systems
It will be found in planning a system of telephone lines for large areas of timber-
land that two general cases may be recognized, and the arrangement of circuits must
be governed by these general conditions1.
£XTERNAL SYSTEM
ipervisor
Fig. 3. External telephone system on a forest reserve
1 — EXTERNAL SYSTEMS
It not infrequently happens that the forest to be protected is wholly or in large
part surrounded by settled lands. This is somewhat more common in the United
States than in Canada, but throughout the Prairie Provinces and in parts of British
Columbia as well as in some parts of the eastern provinces this condition exists. If
PLANNING THE TELEPHONE SYSTEM
25
settlement comes well up to the border of the forest land and rural telephone lines
are well developed in the settlements, the most efficient system of telephone communi-
cation can generally be secured by extending these rural lines into the timber to
connect with the headquarters of the various district rangers. In deciding upon
this plan it is necessary to weigh the cost of tolls on the commercial and rural lines,
and the quality of service rendered, against the original cost of installation and the
annual cost of maintenance of an independent forest-protection system. In doing
this it must be remembered that only the main circuits can thus be provided for.
It still remains necessary to connect the district headquarters with strategic point*
in the districts. A further disadvantage in having the main circuits outside the
forest area lies in the fact that the interior mileage of line, to which connection can
be made by portable telephone, is thereby considerably reduced and the average
distance that it will be necessary for the patrol to go in order to establish connection
by telephone is likely to be materially increased.
2 — INTERNAL SYSTEMS
Whenever, as frequently happens in Canada and in some parts of the United
States, there is little or no settlement along the greater part of the exterior border
of the timbered area it becomes necessary to plan the system wholly within the
forest. Certain general principles hold good for such plans regardless1 of the size of
the area involved, providing it is not so large that circuits of impossible length would
be needed to reach the more remote districts. For purposes of illustration we may
assume an area of 4,000 square miles or approximately 2,500,000 acres. This would,
perhaps, be divided into ten ranger districts, each with a main headquarters. Eight
lookout stations and 20 to 28 patrolmen and " smoke chasers " would likely be
required. This, of course, would vary with the many factors that determine the
justifiable expenditure, and cannot be stated arbitrarily.
. INTERNAL SYSTEM
Supervisor
1 Fig. 4. Internal telephone system on a forest reserve
At some central point, preferably with good mail, telegraph, and railway service,
and with large supplies of men and materials, the chief ranger or supervisor will be
located. Obviously, a point as near as possible to the geographical centre of the tract
should be selected for the main headquarters, unless topography or established lines
of communication make some other choice more advantageous. The choice of this
26 METHODS OF COMMUNICATION FOR FOREST PROTECTION
main headquarters, however, is extremely important from every point of view, and
i$ should not be decided upon except after very careful consideration of all factors.
The same is true of the selection of the district headquarters, District boundaries
will usually be established on topographic lines; in a mountain or hill country generally
along ridge tops, in a flat country along large rivers1 or lakes. The selection of main
and district boundaries and headquarters1 must be completed as a fundamental pre-
liminary before beginning the planning of the system of communication.
The main principle to be observed in planning an internal system is to have the
lines radiate from the main headquarters by the most direct route to each district
headquarters. The district headquarters are then used as centrals from which lines
radiate to lookout stations and other important points in the district.
This plan has two important advantages. In the first place each of the several
independent circuits from the main headquarters to the districts will be much shorter
than single circuits connecting several district headquarters on one line. It is always
desirable for the purpose of ensuring the maximum operating efficiency to keep circuits
to the minimum length.
In the second place a break on any of the main lines under this system will isolate
only one district, while under a system of through lines joining a number of districts
all or several might be isolated by a single break.
Section 27 — Connections to Lookout Stations
It is important to note also 'that lookout stations should have direct connection
with the main headquarters as "well as with the district ranger. This makes it unde-
sirable to introduce .a switch between the main line and the lookout station when the
line from the lookout station joins the main line at a district headquarters. Isolation
of lookout stations must be carefully guarded against, and switches are too likely to be
carelessly left open to be tolerated on such lines.
Other important points to consider in planning a telephone system are the location
of test stations, of relay calling stations on extra long lines, and the provision of
alternate routes.
Section 28 — Test Stations
Test stations are points at which, by means of suitable switches, the line may be
broken into sections. Ordinarily they are used for the purpose of determining the
location of line troubles within definite limits, but they may be very advantageously
used for the relaying of calls over a long or a poorly insulated line. For this purpose
it is desirable that they be located at stations where switching service can be relied
upon.
Section 29— Relay Stations.
Relay stations are points on very long lines where it is necessary to repeat long
distance calls. With the equipment used on forest telephone lines it is nearly always
possible to talk much farther than it is possible to signal with the call bells. Circuits
must not be planned to operate regularly on this basis, however, but in very large
contiguous areas conditions sometimes occur which make it desirable to consider the
possibilities for relaying calls. Under such conditions relay stations may be employed
and they must be located at points where continuous switching service is available.
Section 30 — Alternative Routes
Alternative routes are secured by building connecting lines across the relatively
short gaps that sometimes occur between the ends of separate branches. They make it
possible to reach each station on both lines from two different directions and, therefore,
greatly reduce the chance of any one station being cut off from communication. Since
SELECTING THE TYPE Of1 CONSTRUCTION 27
they are not usually depended upon for regular service they may be very cheaply con-
structed. Often emergency wire laid only during the fire season is employed for this
purpose.
These lines shou'ld, if possible, 'be entirely isolated from the regular lines except
when in use, unless they are of standard construction. They can generally be rather
easily maintained because they are short and have occupied stations at each end.
Whenever possible one such station should be a lookout, thus affording an alternative
route to the lookout station and ensuring continuous switching service at one end, at
least, of the closing line during the fire season.
Section 31 — Secondary Strategic Points
Needless to say, there are many points within or adjacent to a forest area other
than headquarters of the protection staff which may advantageously be included in the
system of communication. These are usually included in the general term, " strategic
points," and include logging, mining, construction, and other similar camps, local
settlements, stores, summer resorts, power stations, saw-mills, boat landings, stage
stations, ranches, and, in fact, any point where either labour or supplies may be secured
in an emergency, or from which reports of fires burning in or adjacent GO the forest
may be sent. As far as is practicable, the main system should reach these points.
Those not so connected may subsequently be reached by spurs if desirable.
CHAPTER V
SELECTING THE TYPE OF CONSTRUCTION
FOT forest-protection purposes two principal types of construction have been
employed. These are pole lines and tree lines. Pole-line construction, as used on forest
lines, differs in no material aspect from ordinary rural-line methods. Several simple
manuals of construction have been published setting forth these methods in detail
but for the purpose of making this manual of communication complete a description
of these methods will be included.
Section 32 — Pole-line Construction
Briefly stated a pole line consists of poles of a specified length set firmly in the
ground at specified, uniform intervals and bearing glass or porcelain insulators to
which the line wire is rigidly attached by short tie wires. Pole lines are as straight
as possible. On curves the wire is always placed on the convex side and the sag
between poles is only sufficient to allow for the normal contraction of the wire with
changes of temperature.
Section 33 — Tree-line Construction
Tree-line construction is radically different from pole-line construction. As a
matter of /act, in most important aspects tree lines are the exact opposite of pole
lines. It is important that this be noted, especially when employing linemen who
have had previous experience in the building of pole lines. Such experience always
predisposes them to follow methods that produce very faulty tree lines, and sucji men
must generally be more carefully supervised when first put on tree-line work than
men who have had no previous experience whatever.
Briefly stated, tree lines consist of trees of varying sizes, at varying but as nearly
as possible equal distances apart, trimmed of branches on one side to a specified
28 METHODS OF COMMUNICATION FOR FOREST PROTECTION
height above the ground; and serving as supports for a special two-piece porcelain
insulator through which the lime wire passes without being rigidly attached. Tree
lines are never straight as are pole lines. On curves the line wire is always placed 011
the concave side and there is a very much greater allowance for sag than that required
for normal contraction of the wire. Supports on tree lines are generally about 65
per cent greater in number than on pole lines, and sag allowance is from four to six
times as great.
Section 34 — Construction Methods Contrasted
Pole lines are built only in open country and along cleared roads or, if they
must be carried through timber, a sufficient right of way is cleared to ensure that
trees will not fall across the line. They are built rigidly and the wires are expected
to stay up unless the poles themselves give way.
Tree lines are designed to be built only through standing timber, where no
attempt is made to clear a sufficient right of way to ensure against falling timber.
Instead, special construction is used for the purpose of ensuring that when trees fall
across the line, the wire will be carried to the ground without breaking or, in case
a number of trees fall in a short distance, the tie wires will break and a considerable
portion of the line wire be brought to the ground still unbroken.
A further danger that tree-line construction overcomes arises from the swaying
of the supporting trees in the wind. This does not occur in pole lines but is quite
obviously a matter of some importance in tree lines. In short, tree lines are designed
to give way and- fall to the ground when subjected to unusual strain ~by falling timber
but any breakage that occurs is designed to come in the tie wires and not in the line*
wire. The underlying principle is that a broken line wire means a dead circuit but
a line wire of a grounded circuit may still function as a telephone circuit when a
large part of it is on the ground, or even when buried under dry snow. If the ground
is damp it will function very imperfectly and if it lies in a stream or pool of water
it is no better than a broken wire, but a considerable portion of a grounded circuit
may lie on ordinary dry or frozen ground without entirely destroying the usefulness
of the line for telephone purposes.
Tree lines, however, have certain very definite limitations. It is impracticable to
use copper wire with this type of construction. This limits the length of tree lines to
.about 125 to 150 miles using No. 9 iron wire. If it is necessary to build a metallic
circuit to ensure against induction it is not practicable to attach both wires to the
same supports, as is done with pole lines, but two separate parallel lines must be built.
Tree lines are never as perfectly insulated as are standard pole lines and, therefore,
are more subject to losses of current and other difficulties in transmission. This is
true no matter how well they are built and is inherent in the methods and line equip-
ment employed.
Section 35— Relative Cost of Different Types
It is a mistake to assume that a tree line is necessarily cheaper than a pole line
even where there are sufficient trees available to, furnish supports for the line. Par-
ticularly is this true when maintenance charges and operating efficiency are taken
into consideration.
The only cost elements of pole-line construction that are greater than those of
tree-line construction are the cost of the poles set on the line and the cost of right-of-
way clearing. The cost of the former will vary with the accessibility and durability
of poles, facilities for distribution, and character of the soil as regards cost of digging
holes. The cost of the latter depends on the nature of the forest and underbrush.
On the other hand all other cost elements are likely to be higher for tree lines
than for pole lines. It is never advisable to use smaller wire than No. 9 B.W.G. iron
wire on a tree line. On a pole line, however, No. 12 B.W.G. iron wire may be used on
SELECTING THE TYPE OF CONSTRUCTION 29
circuits up to 25 to 30 miles in length. This has only one-half the weight of No. 9,
and both the first cost and cost of transportation are, therefore, reduced one-half.
There are nearly twice as many tfes on a tree line as on a pole line. The cost for
insulators is, therefore, considerably increased. As split tree insulators generally cost
more per thousand than pony glass insulators and brackets together, this cost is more
than doubled on a tree line.
Stringing wire costs materially more on tree lines than on pole lines. This is
true even with experienced labour. The most obvious cause of greater cost is the
much greater number of ties to be made, as previously mentioned. Further, it is
harder to reel out wire for a tree line, and care must be used to get the wire on the
right side of each tree; which is less necessary with poles. Trees are also harder to
climb than poles, especially where they are large or have a loose, scaly bark, and it is
necessary for the linemen to spend much time trimming the trees as they ascend them.
Finally, the wire cannot be stretched to give the proper sag allowance in half-mile
spans as it can with poles, but the sag must be distributed from tree to tree by the
linemen often with the constant assistance of a groundman.
The most difficult element in tree-line construction, however, is the problem of
securing efficient labour and supervision. In pole-line work, methods are largely
standardized and relatively simple for lines of only one or two wires, such as those
used for forest telephone circuits. About the only problem requiring the exercise of
judgment is the bracing and guying of poles on curves and at abrupt turns. In tree-line
work, on the other band, nearly every support presents a new problem. Experienced
builders of tree lines are practically non-existent in Canada, and attempts to use line-
men experienced in ordinary pole-line methods have usually been attended with very
unsatisfactory results. Unless, therefore, a large enough mileage of tree line is to
be built to justify the training of special line builders, or unless an experienced fore-
man is available, it will be found more satisfactory to employ the standard pole-line
methods even in timbered regions. This will be quite generally true where the timber
stand is relatively light, making the clearing of a right of way easy, and where suit-
able poles of durable species are readlily secured along the line.
Where a large mileage of line is to be built in big timber, or where the line passes
in large part through large fire-killed, dead, or overmature timber where windfalls are
frequent and the cost of right-of-way clearing would be prohibitive, tree-line methods
are often the only practicable construction that can be employed. These methods are
described in detail in this manual, and if the purpose of the peculiar type of con-
struction employed is understood and the methods prescribed are followed1 faithfully
and intelligently entirely satisfactory lines may be built through the most unfavourable
timber at very reasonable cost.
Section 36 — Sketch of the Development of Tree-line Methods
Although thousands of miles of so-called tree lines have been built by railway
construction companies and others for temporary use, the credit for devising a method
by which tree lines may be built to be of permanent utility belongs to the United
States Forest Service. This service has approximately 25,000 miles of lines in use on
the National Forests of the United States, a large part being tree lines, and is con-
stantly extending these lines as funds become available. The experience on which its
methods are based has been secured under the personal direction of expert telephone
engineers on thousands of miles of line constructed over a period of fifteen years.
Beginning with the makeshift methods of construction commonly employed for
temporary low-priced lines by railway contractors, there has rapidly been developed
under actual working conditions a low-priced method for building permanent lines
specially adapted to forest conditions, and a large amount of equipment has been
designed to meet the special conditions encountered on these lines. The first tree
lines built followed rather closely pole-line methods. These rapidly became useless.
30 METHODS OF COMMUNICATION FOR FOREST PROTECTION
A less rigid type of construction being evidently required, the line wire was hung in
loops from the insulators instead of being rigidly wired to them. This was quickly
superseded by a porcelain knob which took the place of the wire loop, and these in
turn were displaced by the split porcelain insulator. The latter has undergone several
important modifications from the original style in order to meet field conditions more
perfectly.
Meanwhile, there has been a steady improvement in the method of attaching the
insulators to trees. Plain wire hangers fastened with fence-staples were first employed.
These have given place to various other forms of hangers and fasteners until there are
now a variety of improved methods of attachment suited to special conditions. The
importance of abundant slack and of equalized spans was not at first fully perceived.
Experience soon demonstrated that these features of tree-line construction were vital,
and, however much the appearance of the resulting line might depart from previously
accepted standards, the conditions had to be met.
Simultaneously there were developed several improved forms of instruments for
field use. At first the only portable instruments available belonged to two very
specialized classes — linemen's test sets and military field sets. The latter were not
readily procurable, were expensive, and were not well adapted for use with the types of
station equipment generally employed on forest lines. The former, although cheap
and adapted to the station equipment, were heavy if sufficiently powerful, awkward to
carry, and poorly designed for rough usage. By combining the good points of each
class a portable telephone of less than 10 pounds weight was first designed. Sub-
sequently, by adopting from military telephones the vibratory system of signalling, a
field set of only 2 pounds weight was obtained.
While both the methods and equipment have been thoroughly tested in the field
and are known to be reliable, nevertheless, the Forest 'Service engineers would be the
last to claim that their methods are susceptible of no further improvement. In fact,
new methods are constantly being devised and this is especially true where forest-pro-
tection lines are built in new regions. Several novel conditions have already been
encountered in 'Canada that have called for special methods, but changes in methods
by inexperienced builders where field conditions present no striking novelties are to
be avoided. The .author has seen this attempted with distinct lack of success on
several occasions and wishes to strongly deprecate any attempts by inexperienced
tree-line builders to improve on the methods of the Forest Service as reprinted in this
manual.
Section 37 — Influence of Timber Conditions on Choice of Construction Type
A word about the types of Canadian timber to which one or the other of these
methods is likely to be better adapted may be in order. In many Canadian forest
regions untimbered areas of greater or less extent occur. These are more common in
western than in eastern forests and are particularly abundant in the Rocky Mountain
forests and in the drier portions of the British Columbia interior. Wherever it is
possible to build forest lines in these open meadow lands it should be done. If
durable poles are reasonably accessible the first cost will be only slightly increased, and
the greatly reduced maintenance charges and superior transmission secured will
amply justify any small extra expenditure for construction.
1 — MERCHANTABLE TIMBER
The types -of timber most favourable for tree-line construction are those with
little or no underbrush and only moderately dense stands of trees of small size (10 to
15 inches in diameter at breast-height), with trunks clear of branches to a height of
20 to 25 feet or with only small pin branches, and with thin, tough bark. To these-
belong; the lodgepole pine stands of the West, which are the most favourable of all
SELECTING THE TYPE OF CONSTRUCTION 31
stands for tree-line work, and the jack pine stands of the East. Somewhat less favour-
able are the stands of eastern red pine, of western larch and western yellow pine in
mixture, Douglas fir on the drier soils, and some of the larger-sized pure poplar stands
both East and West.
Next to these species in ease and low cost of tree-line construction are such stands
as western white pine (where relatively pure), eastern white pine, mixed hardwoods
in the East, Engelmann spruce and amabilis fir at high elevat.'ons, and the larger-
sized western yellow pine and Douglas fir o>n dtry sites. In the first three the under-
brush is likely to be heavy and the bark thick on old trees or the branches abundant
on young trees. In large yellow pine and fir some difficulty is experienced in climbing
trees because of their size and loose bark, and where trees stand in the way of the
line they are very costly either to fell or to trim up. High-altitude stands are usually
fairly clear of underbrush and the trees are a fair size if usable at all, but the branches
are dense.
The most difficult types through which to build tree lines are Do'iiglas fir on wot
sites on the Pacific coast, white spruce or red spruce, Engelmann spruce at low ele-
vations, cedar, and, above all, hemlock, especially western hemlock. The mixed coni-
ferous forests of the moister regions of British Columbia come under this head, as
well as a great deal of the northern forest belt and the eastern spruce forests. The
difficulties encountered in these types arise from the large amount of underbrush*
that has to be cleared, the density of the timber, and the low-branching habits of these
species. Hemlocks are particularly bad because the lower branches are excessively
long and have a very pronounced downward sweep. Often large branches of hemlock
have to be cut from trees standing 15 to 20 feet fco one side of the line in order to free
the wire.
2 — YOUNG TIMBER
In building lines through very young- timber or reproduction of any species there
is often no choice as to type of construction, that may be employed, since none of the
young trees may be large enough to serve as supports. Very often, however, there are
standing dead snags as remnants of the original forest, which may be so utilized.
Unless the necessity for economy is very great or poles are extremely inaccessible, the
use of such snags for long lines is not advisable. If used, care should be taken to see
that as many as possible of the dead trees adjacent to the line are felled, that abundant
slack is left in the line, and that it is made easily accessible for the purposes of repairs,
as maintenance charges are likely to be high. The continued felling of nearby snags
should be made a part of the regular work of the protection staff and a gradual replace-
ment of the tree line by a pole lime should be the object of the maintenance work.
If young timber, of such a size that trees large enough to furnish supports are
available, is encountered very careful consideration should be given to the advisability
of adopting pole-line construction. A decision will be based largely on the cost of
right-of-way clearing which is determined by the size and especially by the density of
the young stands. Where these are very open, pole lines will usually be preferred.
A makeshift method of construction sometimes adopted under these and similar con-
ditions consists in making the necessary right-of-way clearing, often in the form of a
wagon ro'ad, but leaving at the required intervals suitable trees to serve as the sup-
ports for the telephone line. These trees should not be topped. The cost of making
arid- setting poles is thus saved but it must be realized that a line thus located is likely
to interfere with the use of the road and that provision for replacing these supports
with poles must be made a part of the work of line maintenance.
A similar situation is often met by the builder of forest telephone lines, even in
certain species of timbers of commercial size in the forests of the Prairie Provinces
and of the East. This is most likely to be the case in poplar or jack pine stands.
Both species frequently grow in rather open forests, and where they occur in such
stands righl-of-way clearing is comparatively inexpensive. Moreover, unless th«
32 METHODS OF COMMUNICATION FOR FOREST PROTECTION
poplar is old and defective, windfall is light and the width of clearing need not be
excessive — 20 to 25 ft. in stands of sound green timber not over 40 to 50 ft. high being
adequate. Care should be taken to cut all snags or defective trees, outside this right
of way, that threaten to fall on the line.
3 — DEAD TIMBER
There remains then only the question of dead standing timber. This is the most
troublesome kind of .stand through which to build and maintain a telephone line.
Whenever possible, such timber should be carefully avoided, even at the expense of a
material lengthening of the line. The foregoing applies not only to forests in which
all the trees are dead but also to forests in which a considerable proportion of the trees
are dead or badly decayed and where windfalls are consequently frequent and such
forests are extremely undesirable along the line. Where, as sometimes happens, it is
entirely impossible to avoid constructing through such stands and an adequate right
of way cannot be cleared, then the most careful attention must be given to the details
of tree-line construction and the line must Toe constantly maintained in first-class con-
dition. This latter is of extreme importance because the accumulation of several
fallen snags across the line in a short distance will take up all the slack and cause the
intervening portions to be drawn up very tightly. If this tight wire should happen to
be caught on a projecting branch, or even if the ties fail to break as quickly as
designed, then any new windfalls coming on the line will very likely cause a break.
Even if no break occurs the line is sure to be very seriously strained and a large
number of ties pulled off or broken, insulators smashed, and general havoc created.
Only by careful and conscientious maintenance may lines be kept operating through
large dead standing timber where windfall is frequent.
Section 38 — Grounded versus Metallic Circuits
A grounded circuit is one in which only a single wire is employed for the trans-
mission of the calling and talking currents and the earth is utilized as the other half,
or return portion, of the circuit.
A metallic circuit employs two wires, the extra wire taking the place of the earth
or return portion of the circuit in a grounded line.
Contrary to what appears to be popular opinion it is not necessarily possible to
talk farther over a metallic than over a grounded! circuit. On the contrary, since the
earth for all practical purposes may be assumed to interpose no resistance to the
return currents, provided the ground connections are well made and do not themselves
offer a higher resistance, a grounded circuit will have only one-half the electrical resist-
ance of a metallic circuit under similar conditions. From this it does not necessarily
follow that it is possible to talk twice as far over a grounded circuit, because conditions
other than the mere electrical resistance of the intervening wire have an important
influence on the possibilities of long distance telephonic transmission. The usefulness
of metallic circuits arises from the possibilities of eliminating from them, by suitable
transpositions, all induced currents from other electrical circuits such as power, light,
telegraph, or telephone lines that may exist in their vicinity. The extraneous noises
or cross-talk on a grounded circuit of even short length which runs close to such cur-
rents often make distinct speech transmission impossible, regardless of the electrical
resistance of the line itself. By using a two-wire, or metallic, circuit such interference
from outside sources may be eliminated by transposition, and communication is thus
rendered possible where a one-wire, or grounded, line cannot be used at all. Where,
however, difficulties in transmission arise, not from interference by induced currents
but from excessive length of lines, poor insulation, bad joints, poor " grounds," or
other defects in construction, the installation of a metallic circuit will give no relief.
Excessive line length can only be remedied by using a more efficient conductor. Thus,
CONSTRUCTION POLICY IN FOREST RESERVES 33
the standard galvanized-iron wire used in. ordinary forest lines would have to be
replaced by a larger wire or preferably by copper wire, which is a much more satisfac-
tory electrical conductor than iron wire. If the trouble arises from faulty construc-
tion it can only be remedied by removing these faults. The installation of a second
wire would, otherwise, be more likely to increase than to decrease the difficulties.
For forest-protection purposes a grounded line is nearly always preferable to a
metallic line. As previously stated, only grounded lines can be satisfactorily employed
in tree-line construction. The employment of two wires not only magnifies the chance
for interruptions due to breaks in the line but also renders a metallic line liable to
interruption from short circuits in ways that do not occur with grounded lines. Thus,
if the two wires became crossed, as would often happen when a tree fell across the
line, or if a wet branch or a loose tie wire fell across both wires, the line would fail
to work. Metallic circuits, therefore, should as a rule only be used on full pole lines
and then only when needed to counteract interference from induced currents. Where
disturbances due to induction are encountered in only a part of a line, it is not neces-
sary to make the entire line a metallic circuit, but only that portion where the dis-
turbance occurs. The means by which this is accomplished will be discussed in
Chapters XII and XIY (See Figs. 56, 58, 59, 60 and 86).
CHAPTER VI
TELEPHONE CONSTRUCTION POLICY IN DOMINION FOREST
RESERVES
Section 39 — Construction by the Forestry Branch
The intention of the Forestry Branch is to secure efficiency of fire protection on
the forest reserves by such specialization as the controlling factors seem to warrant.
This will involve the establishment of rapid means of intercommunication. To
accomplish this, telephone lines have been built and will be extended- wherever their
use will ensure more effective fire protection and more economical administration, and
where the territory covered is not served, or probably will not be served, by com-
mercial lines on account of inaccessibility and absence of subscribers. In general,
telephone lines on the forest reserves will be located in accordance with the principles
already discussed in Chapters IY and Y.
For the most part, the commercial telephone lines near the forest reserves are own-
ed and operated by the government of the various provinces, except in British Columbia
where they are largely operated by the Dominion Department of Public Works.
Wherever feasible, these lines should be utilized in order to lessen the necessary con-
struction of Forestry Branch lines.
Section 40 — Co-operative and Private Lines
Co-operation between the Forestry Branch and companies, individuals, provinces,
or other government departments that would involve joint ownership, construction, or
maintenance of telephone lines, introduces a division of responsibility which may affect
communication and maintenance as well as future growth and extensions, and, there-
fore, should be avoided. Exceptions may be made in the case of the lines of the
Department of Public Works in British Columbia and, in unusual instances, in the
case of provincial telephone departments, but all such instances must be referred to the
Director of Forestry for approval.
79211—3
34 METHODS OF OOMMUNICATWN FOR FOREST PROTECTION
The construction of privately owned lines within the reserves should be encouraged.
Permits for such lines, when they will be of material benefit to the forest reserve should
be recommended for issuance under Regulation 65 (" Regulations for Dominion Forest
Reserves," 1916) and the conditions varied so as to afford the necessary encouragement
in each case. Regulation 21 authorizes the granting of free construction materials
for structures on roads and trails on condition that they become the property of the
Crown, and Regulations 18 and 19 provide for the furnishing of materials at special
rates when the removal of the material will benefit the reserve. Supervisors, therefore,
should accompany all recommendations for issuance of permits for the construction
of private telephone lines within forest reserves by a report regarding the class of
construction materials that it will be necessary to obtain from the forest reserve, if
any, and a recommendation regarding the price that should be charged in case special
consideration is believed justifiable. Free service for a specified number of connections
made by the Forestry Branch on all such lines will be made a part of all such permits.
Section 41 — Use of Forestry Branch Lines
The connection of privately owned instruments with Forestry Branch lines will
not be permitted. The conditions under which these lines are constructed and main-
tained necessarily reduces to a minimum the number of telephones that may be operated
on them. Each telephone adds to the electrical load and lessens by this amount the
reserve capacity for future growth and, more particularly, for emergencies. Under
no circumstances can such a number of instruments be regularly connected to a
Forestry Branch line that its entire capacity is employed, since the exigencies of forest
administration may at any time require the establishment of one or more additional
temporary connections with portable instruments or emergency lines. The possibilities
of extensions are also extremely important in this connection. A line 10 miles long
might easily carry ten to fifteen telephones, but if this line is extended to form part
of a circuit 100 miles long the probability is that all but one or two of these telephones
would have to be removed in order to get any use of the line. Now, it is found that
where telephone service has once been granted in an isolated region it is relinquished
only with the greatest reluctance and therefore forest officers should weigh all these
points very carefully when considering any connections other than those at ranger
stations.
All instruments connected with a Forestry Branch line will be provided, installed,
and maintained by the Forestry Branch. Instruments may be installed by super-
visors at logging camps, mines, or other private establishments, but only where such
installations are necessary for the proper administration and protection of the forest,
where suitable arrangements can be made for the protection of the instrument and
the securing of access to it by forest officers at all times, and only after approval of the
installations has been received from the district inspector. It will be the duty of
supervisors contemplating such installation to report fully to the district inspector the
conditions which warrant the placing of an instrument at that point, the character of
the building in which it will be placed, and the service that may be secured, and to
report annually as to the advisability of maintaining or discontinuing the installation.
Such stations will, as a rule, be located only in buildings of a public or semi-public
character such as stores, post offices, hotels, road-houses, logging-camps, etc., and only
where the location is of material importance to the reserve work and the person owning
the establishment is under agreement to perform some special service for the Forestry
Branch.
The telephone lines of the Forestry Branch are not to be considered commercial
in character. It is not the intention to enter into competition with any private or
provincial telephone service. Hence no action such as the granting of telephone ser-
vices to settlers along these limes, with an annual charge for the privilege, will be
permitted. It is obvious that any such permits will inevitably raise the question of
CONSTRUCTION POLICY IN FOREST RESER^7ES 35
discrimination, since it is wholly unreasonable to expect that such service can be
granted to all that may apply, as1 would be done on commercial lines. These lines
are built for the specific purpose of assisting in the administration and protection of
the forest reserves, their capacity is extremely limited, the connections needed by the
Forestry Branch are subject to sudden and unforeseeable increases, and accidents
to which these lines are particularly liable may at any time very 'greatly impair their
carrying capacity. For these reasons any attempt to render commercial service will
inevitably fail, and no connections will be made Which are not in the opinion of the
supervisor and the district inspector essential to the proper administration and pro-
tection of the reserve.
Forestry Branch lines, however, are open for public use free of charge so far as
the portion of the line owned by the Forestry Branch is concerned. Where provincial
or other foreign lines are used in connection with a forest line the usual toll charges
must be paid.
Section 42 — Telephone Improvement Plans
Within one year after the issuance of these instructions all supervisors and rangers
in charge of Dominion forest reserves asre required to prepare and submit to the
district inspector and the Director of Forestry a complete plan for the equipment of
the reserve with telephone lines. This plan will include a map and a report
The map should show existing Forestry Branch and private lines and their
character, and the location of exchanges and instruments, also the location and
character of all new construction which will be necessary to meet the needs of Forestry
Branch business during the next five years. In addition, the map should show high-
tension electric transmission lines, roads, trails, ranger stations, lookout stations, and
all other features which may influence the establishment of the system.
The report should discuss, in the order of their importance, the proposed new
lines, their need, location, character, and cost. The telephone system should be
grouped by natural divisions, eaich being designated by its two terminals. A branch
line should be designated by its terminal and the division of which it is a branch.
The district inspector will prepare, from the information furnished by the
supervisors, a map of the entire district showing the existing and proposed lines.
This will ensure co-ordination of plans between the various reserves and with private
systems. He will then issue instructions covering the general plan of the telephone
system for each reserve.
Section 43 — Standard Methods
Since the Forestry Branch lines are primarily for fire protection purposes they
should embody the best principles of construction, and every precaution should be
taken to ensure continuity and dependability of communication over them at all
times and especially during fire seasons.
1 — DESIRABILITY OF STANDARDS
To ensure that the best principles of construction shall be followed on all reserves
it is essential that the direction of telephone development be centralized and this
necessarily involves the issuance of uniform standard instructions. Such standard
methods may be based on the experience, not alone of all the various Forestry Branch
officers, but also on that of other protection services, and new discoveries or improve-
ments can, therefore, be applied generally throughout the forest reserves. Moreover,
it is only by employing standardized methods that the use of standard equipment is
made possible.
2' — AMOUNT OF LINE WARRANTED BY PROTECTION STANDARDS
As yet, the determination of exact standards of protection on forest lands in
Canada has progressed only a relatively short dietanct*. It is possible to give only
79211—3*
36 METHODS OF COMMUNICATION FOR FOREST PROTECTION
very general statements in regard to the actual degree of immunity from fire damage
that may be considered satisfactory in specific instances, consequently, it is possible
to state only in a very general way the amount of line that may be considered essential
in any given case: On the forest reserves, where continuous forest production must
be aimed at in order to justify their existence, it is obvious that if the area annually
mimed over averages more than about 1 per cent this aim will be rendered wholly
unattainable. It is doubtful, moreover, whether with an average annual fire loss
exceeding one-tenth of 1 per cent (1 acre per 1,000) of the area protected satisfactory
results are possible. Certainly an average annual loss of 2 acres per 1,000 in the
reserves of the P'rairie Provinces should be the outside limit. 'What expenditure may
justifiably be made to attain this degree of protection depends on many factors, not
all of which are as yet known in these forests. From a study of protective services in
other regions, however, it may be said that present protection standards on Dominion
forests demand the connection of all district ranger headquarters with the supervisor
by telephone, and the equipment of primary lookout stations at least. Further con-
struction can only be of real utility as the efficiency of the staff develops and as its
further specialization becomes feasible. In a general way an- internal system that will
connect all district headquarters with the supervisor will be found to involve about
200 miles of line to each million acres of forest. Since this is a greater mileage than
can be successfully operated on one circuit, it is necessary to divide it into two or more
independent circuits in preparing the telephone plan.
Section 44 — Standard Materials
1 — DESIRABILITY OF STANDARDS
Several factors combine to render the adoption of equipment standards impera-
tive.
Certain technical reasons require the use of uniform types of instruments on the
one circuit.
Only by adopting a standard type for all circuits is it possible to connect up
adjacent ones or to transfer equipment from one to another.
Some important special instruments are manufactured for use only with certain
types of equipment. Unless these types are employed it is impossible to utilize all
the available facilities.
Dealers will carry in stock only materials for which there is a reasonable demand.
The adoption of uniform standard equipment for all the work of the Forestry Branch
will make it possible for dealers to carry at local distributing- centres a supply of this
material, and thus greatly expedite deliveries.
For the purpose of providing uniform equipment throughout the Dominion forest
reserves the following standard list has been adopted and must not be deviated from
without the authority of the district inspector.
2 — LIST OF STANDARD EQUIPMENT
NOTE. — For specifications of those items marked with an asterisk (*) see Appendix E.
Material and Uses Description of Equipment
*Wire: —
Standard
Line (pole and tree, grounded and metallic). No. 9. B.W.G., B.B. galvanized-iron telephone
wire.
Specials
Line (special long distance tree lines,
grounded only) No. 6 B.W.G., B.B. galvanized-iron telephone
wire.
CONSTRUCTION POLICY IN FOREST RESERVES 37
Material and Uses— Con. Description of Equipment — Con.
Con.
Line (special short pole lines only) Nos. 12 and 14 B.W.G., B.B. galvanized -iron
} telephone wire.
Line (special extra long distance pole lines
only, mostly metallic) Nos. 8 and 12 and 14 B. & S. gauge hard-drawn
copper as required.
Line spans, 500 feet and over Steel wire as required.
Emergency lines No. 20 stranded, consisting of 10 strands of No.
30 B. & S. gauge, hard-drawn copper wire,
insulated.
From line to fuse No. 14 B. & S. gauge, rubber-covered, braided,
weather-proofed copper wire. Single for
grounded line, twisted-pair for metallic.
From fuse to protector No. 14 B. & S. gauge, rubber-covered, braided,
weather-proofed copper wire. Single for
grounded line, twisted-pair for metallic.
From protector to all inside apparatus, in-
cluding telephone No. 19 B. & S. gauge, rubber-covered and braided
copper wire. Single or twisted-pair.
From protector to ground No. 14 B. & S. gauge, rubber-covered, braided
and weather-proofed copper wire. Single.
From line wire to portable telephone Special Forestry Branch portable connector.
"Poles : —
Line supports (standard) 22J ft. long by 6 in. diameter at top. Green, or
sound dead, peeled cedar, or other species,
with open tank butt treatment.
Line supports (special) 18-ft. to 45-ft. cedar poles for special construc-
tion. Species other than cedar with
special treatment.
Attachments, Wire to Poles : —
*Brackets 12-in. oak bracket, painted or oiled.
Nails 6-in. and 4-in. galvanized-iron wire nails.
"•Insulators Glass, regular pony long-distance 14-oz., deep
groove for No. 9 iron wire. Glass No.
9 pony for copper and No. 12 iron wire.
Tie Wires No. 9 B.W.G. galvanized-iron wire on No. 9 wire
lines. Nos. 8, 12, 14 B. & S. gauge, soft
copper wire on same gauge copper lines.
Attachments, Wire to Trees : —
Fastener 3-in. or 4-in. wrought-iron staples, according to
bark thickness.
Tie Wires Nos. 9 or 12 B.W.G. galvanized-iron wire,
according to tie employed.
*Insulator No. 37 improved split tree insulator No. 6651.
Linemen's Tools : —
Climbers Eastern type (in ordering state length desired)
straps and pads are supplied separately.
Belts with rings and safety straps 2}-in. (in ordering state length desired).
Pliers, for cutting wire and making ties and
splices /.8-in. linemen's side-cutting, with sleeve-twister,
Klein make or equal.
Combination wire and sleeve splicing-clamps,
for making splices Reversible for sleeves (Nos. 8 to 12) and wire
(Nos. 6 to 14), Klein make or equal.
38 METHODS OF- COMMUNICATION FOR FOREST PROTECTION
Material and Uses — Con. Description of Equipment — Con.
Linemen's Tools — Con.
Hand-axe for trimming trees and driving
nails and staples 26-oz. Hudson Bay hand-axe with 22-in. handle.
Mclntyre sleeves, for splicing copper wire..Nos. 8, 12, and 14 copper Mclntyre sleeves for
copper wire only.
Pole-setters' Tools: —
Shovels, for digging holes for poles 7-ft. handle, round point.
Digging spoons, for digging holes for poles.. 7-ft. handle, flat-toed, medium.
Combined digging spud and tamping bar, for
digging holes and tamping poles in soft
ground S-ft., steel.
Digging and tamping bar, for digging holes
in gravel or hard ground . 1-in. octagonal steel, 8 ft. long.
Specials
Pike-poles, for raising and steadying' poles
30 ft. and over in length 12 ft., 14 ft. and 16 ft. long, according to length .
of poles.
Pole supports, for raising large poles Mule or jenny pattern, generally made on the
job if required.
Post-hole auger, for digging holes in soft
ground 10-in. auger, Iwan's type with 6-ft. handle.
Guys and Braces : —
Bolts, for holding top of brace to pole g-in. galvanized-iron bolt, square head, square
washers, 2J by 2| by %6 in. and nut.
Lengths according to size of poles.
Guy rods, for fastening guy wires to anchor
logs i-in. diameter by 5 ft. or 6 ft. long, galvanized-
iron with washer and nut.
Guy wires, for guying poles at sharp turns,
long spans, etc Nos. 9 or 12 B.W.G. galvanized-iron wire, 2 or
4 strands, twisted.
Line-stringing Tools : —
Pay-out reel, pole and tree lines Horizontal type only. Made on job according to
specifications.
Pay-out reel, emergency wire lines Special Forestry Branch hand-reel made to order
only.
Buffalo grips, for holding and stretching wire
on pole lines only Buffalo grips with pulley for No. 9 wire and
smaller.
Haven clamp, for holding and stretching guys
and line wire Haven clamp with 2-in. to 3 -in. double blocks
and 36 ft. of |-in. sash cord.
Telephone Instruments : —
For supervisors' offices Desk set: type, Northern Electric No. 1300-A or
equal. (Note. — When it is desired to
equip a desk set with a head receiver the
district inspector will advise as to the
equipment to order).
For lookout stations, permanent Same as for supervisors.
For ranger stations permanently occupied. . .Wall set; type, Northern Electric No. 1317-S or
equal, with 2,500-ohm unbiased ringer and
condenser.
CONSTRUCTION POLICY IN FOREST RESERVES 39
Material and Uses — Con. Description of Equipment Con.
Telephone Instruments — Con.
For ranger and patrol stations unoccupied
during winter months, open lookout towers
and any outdoor stations along patrol
routes or elsewhere Weather-proof iron box telephone; type, North-
ern Electric No. 1336-J or equal with
2,500-ohm unbiased ringer and condenser.
For speeder patrolmen, special crews, or fire-
camps on lines not equipped for buzzer
signalling Special Forest Service portable telephone;
Northern Electric No. 1375-A.
For patrolmen, special crews, " smoke chasers"
and all field service units on lines
equipped for buzzer signalling Special Adams portable telephone; Northern
Electric No. 1004-A.
Emergency Telephone Kits : —
For temporary camps on fires or special pro-
jects Special Forestry Branch emergency communi-
cation kit No. 1-A.
Protective Devices : —
Lightning-arrester, for lightning only Protector; type, Northern Electric No. 60-E or
equal. Order separately protector blocks,
Northern Electric Nos. 20 and 21 or equal,
and No. 10 protector block mica.
Lightning-arrester, for lightning and high-
tension currents Protector; type, Northern Electric No. 5S-F or
equal. Same as above with addition of
2-ampere to 7-ampere No. 11-C tubular
fuses.
Fuses, for outdoor installation Type, Northern Electric No. 4 7- A or equal.
Protector blocks and micas for repairs . . . . Protector blocks ; type, Northern Electric Nos.
20 and 21 or equal. Protector micas ;
type, Northern Electric No. 10 or equal.
*Svvitch and protector mounting-box, for all
permanent outdoor telephones Type, Northern Electric No. D-400 or equal.
Protector mats, to be placed under No. 58-F
protector Type, Northern Electric No. 48 or equal.
Lightning rods, for carrying lightning to
ground, on pole lines only No. 9 B.W.O., galvanized-iron wire, 2-in.
galvanized-iron fence-staples.
Dry Batteries : —
For station telephones, desk and wall sets ... Type, Northern Electric "3 in 1" battery Blue
Label, or equal.
For weather-proof lookout telephones Type. Northern Electric telephone battery or
equal.
For Forest Service • portable telephone No.
1375-A Columbia O.V. No. 3 or Ever Ready Tungsten
No. 703.
For Adams portable Telephone No. 1004-A.. Ever Ready Tungsten No. 705.
Special Signalling Devices : —
Extension bells
For stations indoors Type, Northern Electric No. 127-F or equal, with
2.500-ohm unbiased ringer.
40 METHO'DS OF COMMUNICATION FOR FOREST PROTECTION
Material and Uses — Con. Description of Eqwpment — Con.
Special Signalling Devices — Con.
For statons outdoors Type, Northern Electric No. 292-U or equal,
with 6-in. galvanized gongs and 2,500-ohm
unbiased ringers.
Howlers, for signalling by means of vibratory
currents as with 1004-A telephone Type, Northern Electric No. 1-C or equal.
Condenser, for use with howler to impede
bell-signalling currents Type, Northern Electric No. 21-F or equal.
Repeating Coils : —
For connecting grounded to metallic line or
taking out a phantom circuit Repeating coil; type, Northern Electric, No. 47-
A or equal.
Station Installations : —
Fasteners for outside wiring No. 4i solid, or No. 5| one-groove, split por-
celain insulator; Nos. 14 or 16, 3-in. flat-
head wood screws.
Fasteners for inside wiring, single or double. . J-in. or 1-in. Blake insulated staples.
Fasteners for inside wiring, double only.. . . i-in. milonite nails.
Insulation for wires through walls Porcelain tubes, unglazed, diameter |-in. by
n/ie-in. Length according to wall thick-
ness.
Switches, for test stations, central switching
stations, unoccupied stations, etc Single or double pole 15-ampere baby knife-
switches on porcelain bases.
Screws, for attaching protectors, switches,
howlers, etc., to walls ..Blued, round-head screws, length and gauge
according to size of each article.
Installation and Repair Tools : —
Pliers
For cutting insulated wire 5-in. oblique, side-cutting pliers, Klein or equal.
For tightening binding-posts and small nuts. 5-in. or 6-in. long-nosed, oval, side-cutting pliers.
Screw-drivers
For setting small wood screws 4-in. machinists' style screw-driver.
For setting large wood screws 8-in. machinists' style screw-driver.
For setting screws in instruments 2£-in. machinists' style screw-driver.
Knives, for general insulated wire work.. ..Electricians' knife; type, Northern Electric No.
402 or equal.
Soldering torch, for heating soldering irons. .Clayton and Lambert gasolene blow torch No.
38.
Soldering copper
For soldering joints and other outside work. |-pound standard soldering copper.
For interior work and repairs to instru-
ments Pony soldering copper No 2, ll|-in. handle,
weight, 3 oz.
Installation and Repair Supplies : —
Solder Resin-core flux solder, 1-pound or 5-pound
spools, half-and-half bar solder.
Flux Allen soldering stick, 1 by 5£-in.
TaPe Black friction tape, S-in. Northern Electric
grade A or equal.
CONSTRUCTION POLICY IN FOREST RESERVES 41
Material and Uses — Con. Description of Equip mem --Con.
Grounding Devices : —
Ground rods, for all ordinary indoor and out-
door instrument installations on grounded
lines Galvanized-iron ground rod with copper wire
attached ; i in. diameter by 7 ft. long,
Northern Electric or equal.
Ground rods, for metallic circuits only.. ..Galvanized or plain iron ground rod, J in. dia-
meter by 6 ft. long, Northern Electric
No. 388 or equal.
Ground plates, for special ground installations. Copper plate No. 21 Birmingham sheet metal
gauge or No. 21, U.S. sheet metal gauge;
12 by 18 in. or larger.
Ground clamps, for grounding on water-pipes. . Northern Electric type A ground clamp or equal.
Portable ground rod, for Forestry Branch
emergency communication kit No. 1-A. . Special Forest Service portable ground rod,
Northern Electric No. 313-B.
Miscellaneous Tools and Supplies : —
Brace and bits, for boring holes for brace
bolts and guy rods and for carrying wires
through walls Brace, ratchet, ball-bearing head, 10-in. sweep.
Bits, auger or car bits ; i-in., fj-in.,
ii/ie-in., countersink. Other sizes as re-
quired.
Claw-hammer, for interior installations.. ..Ordinary style; light.
Monkey-wrench, for setting up brace bolts and
guy rods Standard wrench, 12-in.
Pole-steps, for poles over 30 ft. high, bearing
test station or other special apparatus. .Galvanized-iron poles-steps, |-in. by 9-in.
Tree-trimmers, for trimming small branches
from ground ' Type, Northern Electric Co., New Giant tree-
trimmer or equal.
Insulators, strain, for dead-ending line wire
on trees and poles Type, White Strain Insulator No. 500 or equal.
Strand, standard galvanized steel, for attach-
ing strain insulators No. IS double galvanized-steel seizing strand.
CHAPTER VII
OPERATIONS PRELIMINARY TO CONSTRUCTION
Section 45 — Factors Influencing Location
The relation of the proposed line to the telephone system, present and proposed,
should be kept constantly in mind. This will influence the type and character of
construction. If the proposed line is a trunk line the possibility of connecting to it
short branch lines from lookout points and ranger and fire stations should be con-
sidered.
The following additional points should be observed when locating telephone
lines: —
(1) The location of the most logical switching centres for connection with other
lines.
(2) Topographical location. By avoiding steep slopes, cliffs, high divides, river-
beds, coulees, and streams, and canyons more than 500 ft. in width, the danger from
snowslides, landslides, floods, and high winds will be lessened. By following roads
and main trails frequent inspection will be facilitated and maintenance simplified.
(3) Location of other electrical circuits. Electric-light, power, and high-tension
transmission lines should be avoided whenever possible. A high-tension transmission
line carrying over 5000 volts should not be paralleled at a distance of less than -one-half
mile, and all crossings and approaches between telephone and power transmission lines
should be at right angles.
(4) The probabilities of future growth and extensions.
(5) The length of the line. Other costs being equal, the cost of construction
and maintenance varies as the length of the line.
Section 46— Survey of Route
A preliminary survey or reconnaissance is necessary in order that the length of
the line may be ascertained and its cost estimated. The thoroughness of the survey
will depend upon local conditions. A transit. line with chained distances may be
necessary in some cases, while in others a walking or riding reconnaissance will be
sufficient. The location determined by the survey, however, need not be taken as
final; deviations from it should be made if it 's found during the course of construc-
tion that greater reliability can thus be secured.
Whenever a pole line is to be constructed, either in whole or in part, marking
stakes should be set in line at the proposed locations of the holes. Each stake should
be marked to indicate the height of the pole for that particular position, the depth
of the hole, the kind of hole to be dug (whether an anchor-hole or a stub-hole),
whether the pole is to be guyed or braced, and the amount of the rake (Fig. 11) at
curves and corners.
Each tree that is to be used as a tie tree should be prominently blazed fore and
aft, and on the side to which the split insulator is to be attached. A cross made with
blue crayon should be placed on the latter blaze.
Section 47 — Securing Right of Way
If it is proposed to build any part of the line off the reserve, or over alienated
land within the reserve boundary, right of way should first be obtained. The proper
form, which will be furnished by the district inspector, should be used. Verbal per-
mission is not sufficient.
42
Fig'. 5 Mobley wire-cradle as used with two coils
Fig. 6 Mobley wire-cradle as used with one coil
43
44
METHODS OF COMMUNICATION FOR FOREST PROTECTION
In nearly all the western provinces the use of the public roads as the right of
way for telephone lines is controlled by the provincial government. Before any lines
are placed on such roads permission must be secured from the proper government
department. This must in all cases be taken up through the district inspector.
If it is desired to string wire on poles belonging to a private company written
permission should be secured from the inspector before any construction is begun.
Section 48 — Clearing Right of Way
When a pole line is to be constructed, a right of way sufficiently wide to afford
reasonable protection against dlamage to the line from falling trees must be cleared.
It is especially necessary that dead or defective trees that lean toward the right of
way and threaten to fall across it be removed. The effect of snow on adjacent trees
and branches must always be considered, and all that might be borne down across the
line should be cut. As a rule pole lines will not be built in the forest if a cleared
right of way of greater than 25-ft. width is needed, unless the trees are exceptionally
scattered.
]
Fig. 7 Mobley wire-cradle.
When pole lines are carried through small timber or reproduction a right of way
at least wide enough for a saddle trail should be cleared through any dense under-
brush. Small trees directly under the wire, which by their future growth might touch
the wire, should be cut down at the outset. Everything, in fact, that might at pre-
sent or in the near future cause trouble on the line should1 'be cleared before or at the
time the wire is strung.
If the line is to be attached to trees it is not advisable or necessary to top the
trees to which the split insulators are fastened, except where the line has to cross over
a windy canyon or in other places exposed to a strong wind. Under such conditions
the trees should either be topped or else poles used, preferably the latter. It is usually
only necessary to trim the branches on the insulator side of the tree to a sufficient
height for attaching the split insulator. Undergrowth and trees between spans should
OPERATIONS PRELIMINARY TO CONSTRUCTION
45
be trimmed sufficiently to allow at least a 4-ft. clearance of the line wire. Any dan-
gerous snags or rotten trees in the close vicinity of the line should be cut. A right-of-
way clearing for a tree line must usually be at least 8 ft. wide at the height above the
ground at which the wire will hang. This is quite different from an 8-ft. clearing
on the ground, particularly in long-branching species such as spruce, hemlock, and
cedar, but care must be taken to see that sufficient clearing is made before the wire
is strung, as otherwise annoying and costly delays result.
In clearing lines through dense underbrush and reproduction, it will be found
most satisfactory to scatter the clearing crew singly along the line and have all
Fig.
Klondike pack-frame as used for packing wire
material felled into the right of way. The debris resulting from such clearing adds
to the fire-danger and should, if practicable, be burned on the right of way before the
wire is strung. If not practicable, the brush should be piled off the right of way and
left for burning at a time when conditions are favourable.
Section 49 — Transportation and Distribution of Materials
The wire, brackets, insulators, and other equipment should be conveyed? from the
railway point or the place of purchase to the proposed line by automobiles, teams, or
horses. Time and money will be saved if construction work is ndt started until all
necessary line equipment has been distributed to its proposed location or to some con-
venient point. Wire and other metal should be kept off the ground. All line
materials should be distributed along the right of way well in advance of wire-string-
46 METHODS OF COMMUNICATION FOR FOREST PROTECTION
ing crews. Much time will be saved' if the ^-mile points (or J-mile points) at which
coils of wire are to be left are marked in advance of the teams or pack-horses. Use a
blaze with a red cross or some other distinctive mark.
It will often be necessary to pack the wire on horses. The maximum load for
one horse under best conditions is two 4-mile coils of No. 9 wire (weight 104: pounds
each) and under poor conditions, one i-mile coil (weight 157 pounds). Single coils
may be packed on a horse in several ways, but the following method is suggested :
Run a cross-stick lengthwise between the cross-trees on the pack-saddle, tying each
end securely. Then split the coil of wire in half and place it over the top of the stick
connecting the cross-trees, so that one-half of the coil is on each side of the saddle.
Finally, throw a diamond hitch over the whole.
1 — MOBLEY WIRE-CRADLE.
A still better method adapted to packing either one or two coils is to use a pack-
ing-cradle such as the one designed by Ranger Mobley of the Forestry Branch. Thi?
cradle (Fig. 7) consists of a rectangular wooden frame built to fit snugly over the
forks of the pack-saddle. The front and near pieces project a few inches beyond the
sides and two pieces of strap-iron with upturned ends are so placed as to hold the side
coils in place. In packing two coils, one is hung on each side of the horse on the pro-
jecting ends of the cradle and then lashed on with a diamond hitch. When packing
one coil it is laid flat on the top of the cradle and lashed in place. This cradle is par-
ticularly handy when distributing coils along the line, since it is equally convenient
for packing either one or two coils (Figs. 5 and 6). For packing heavy coils of wire
on men's backs the Klondike pack-frame shown in Fig. 8 is an unusually effective
device. f
Section 50 — Organization and Equipment of Construction Crews.
The foreman will be responsible for the work on the line in accordance with the
instructions he receives. Whenever possible he should be a forest officer, carefully
selected for his experience in telephone construction and in (handling men. The size
of the crew will depend upon the extent of the work, the qualifications of the indi-
vidual members, and the time available for completion.
A crew may consist of a foreman, one ground assistant, two linemen, one utility
man (swamper and lineman), and, if necessary, a cook. If more speed is desired, one
or two additional linemen may be employed, provided arrangement is made to
" swamp " the line and distribute materials with sufficient rapidity, to do which may
require one or two additional groundmen. Which members of the crew will dig the
holes, which distribute ttoe material, and which erect the poles will be determined by
local conditions.
Each man employed in digging holes for poles should foe provided with:—
One 7-ft. shovel, Western Union pattern.
One medium weight, straight-handled, flat-toed, spoon, Western Union pattern, 7-ft.
handle.
. One 1-in. by 8-ft. octagon steel digging bar.
In sand or other easy digging a post-hole auger can often be used to advantage.
Each lineman on tree lines should be provided with the following equipments--
One combination wire-and-sleeve splicing-clamp. This is of the reversible type, one side
being used for Mclntyre sleeves and the other for Western Union connection.
One pair 8-in. linemen's pliers.
One pair of Eastern climbers, with straps. These run from 14 to 19-in. in length by
1-in. intervals.
One belt and safety strap.
One hand-axe.
One bag insulators and tie wires.
A construction crew on pole-line work should also be provided with : —
Two Buffalo grips.
One Haven's steel clamp.
One 3-in. double-pulley block (with one hook).
One 3-in. double-pulley block (with hook and eye).
Thirty-five ft. g-in. sash cord.
CHAPTER VIII
POLE-LINE CONSTRUCTION
Section 51 — Selection of Poles
Poles should be cut as near the proposed line as practicable. The best and most
durable timber, such as cedar, tamarack, and Douglas fir, should be used, if it can
be obtained at a reasonable cost.
All poles should be cut from live or dead standing trees and should be free from
heart-rot or butt-rot, or any other defect which might weaken them. As a means
of reducing- the cost of poles delivered at the hole it may in some cases be desirable to
purchase poles from commercial companies.
Whenever possible poles and braces should be cut in winter to secure better season-
ing. They should be peeled as soon as cut and all knots and branches trimmed close.
Unpeeled poles must not ~be used under any circumstances. Poles should be reason-
ably straight and of the dimensions shown in the table below : —
TABLE A— LENGTH AND TOP DIAMETER OF STANDARD POLES
Length of pole Diameter of top Length of pole Diameter of top
ft. in. ft. in.
18 6 35 7
22> 6 40 8
25 6 45 10 to 11
3>0' 6 to 7
When a line will be subjected to severe stresses from high winds or unusual
strains, these diameters should be increased by from % inch to 1 inch. High poles
should be very fine quality. The butts of poles should be cut off square; the tops
should be cut slanting on both sides to form a right-angled " roof " as in Eig. 10.
Section 52— Skidding and Seasoning
It is sometimes possible to collect a number of poles or braces at one point as they
are cut, and later to distribute them along the line without undue expense. In sucih
cases the poles should be completely barked and piled in tiers, with a space of at least
6 inches between poles in the same tier and between tiers. The bottom tier should
be of sufficient height from the ground to allow of the free circulation of air under the
poles, which should be seasoned for at least two or three months. Seasoned poles are
lighter and therefore easier to handle. Poles should not be held in storage too long
as they are liable to start to decay.
When it is not feasible to collect poles or braces at one point, the individual pieces
should be peeled and raised off the ground or leaned against trees or rocks in an open
position to season. Sound dead timber need not be seasoned.
It is particularly necessary, when poles are to be treated with any form of pre-
servative, that they be well seasoned and, so far as possible, be accumulated at a very
few places along the line. In most cases it will be found desirable to prepare such
poles a season before line construction is contemplated'.
Section 53 — Preservative Treatment
If durable woods cannot be obtained at a reasonable cost it may be necessary to
give the poles preservative treatment. Before doing this, however, the district inspector
should be consulted. The poles of branch lines less than 3 miles long need not be
treated in any case, unless the branch is constructed at the same time as a main line
of treated, poles1.
47
48 METHO'DS OF COMMUNICATION FOR FOREST PROTECTION
The experience of the Forestry Branch with untreated' spruce amd poplar poles in
the Prairie Provinces has shown that they have a length of life of only 3 to 5 years.
Eastern tamarack poles are somewhat better, lasting from 6 to 9 years. Experiments
have just been begun with lodgepole pine on Dominion reserves, but experience with this
species in the United States has shown that its dependable length of life, untreated,
is not over 7 years. Jack pine will, probably, be about the same. It is considered
that permanent trunk lines on the forest reserves should be built to last without pole
renewals on a large scale for at least 15 years. This may be accomplished by using
either well-seasoned, untreated cedar poles or well-treated native poles.
Special instructions with regard to the use of untreated and treated poles on
Forestry Branch lines will be issued by the Director of Forestry. There are only two
methods of pole preservation that may be applied with a reasonable degree of success
under the conditions usually encountered on forest protection lines. These are the
" open- tank " method and the " brush method." The latter gives only a very slight
increase in durability and i® only desirable under certain very special circumstances.
The former is the most successful method yet devised for the type of line employed
by the Forestry Branch. Treatment is applied only to the portion of the pole placed
in the ground. In some cases it may be preferable to treat & ft. or 9 ft. stubs and set
poles as explained in Section 91. Before any treatment is applied all adhering bark,
including the inner fibrous bark, should be removed with a draw-knife from the por-
tion of the pole to be treated.
A's the details of the treating apparatus and the methods of treatment have not
yet been standardized for Forestry Branch lines, only a brief reference to these methods
can be made at present amd complete instructions will later be issued in the fo'rm of
a supplement to this manual. In the meantime, pole treatment will only be under-
taken in accordance with specific instructions issued by the district inspectors.
1 — OPEN-TANK METHOD
Wherever practicable, this method of treatment is the best that can be employed.
Creosote, heated to a temperature not to exceed 200° F., is the preservative used.
(See "Preservative Treatment of Poles," United 'States Forest 'Service Bulletin ISTo.
84, and "Preservative Treatment of Fence-posts," Forestry Branch 'Circular No. 6.)
2 — BRUSH TREATMENT
This process requires less equipment than any other, but the results are not
nearly so good as the open- tank method. Brush treatment even when well done can-
not be depended on to add more than 2 or 3 years to the life of a pole. A brief descrip-
tion follows : Hot creosote oir hot carbolineum is applied to the poles with iron-bound
brushes for a space of about 1 ft. above the ground line and 2 ft. below it, thus form-
ing a band 3 ft. wide. All seasoning checks and knot holes should be carefully filled
and the preservative applied as freely as possible without waste, putting on all that
the poles will absorb. After an interval of at least 24 hours the poles should be
treated with a second coat applied in the same manner.
In hot, dry weather the creosote should be heated to a temperature of from 120°
to 150° F. and in cold weather to 180° F. These temperatures, however, should not
be exceeded. In heating the creosote the utmost precaution should be taken to pre-
vent accidents. If the heating vessel is allowed to boil over or if creosote is spilled
and allowed to burn on the outside of the vessel, the contents are pretty sure to ignite
and burn fiercely. If creosote becomes mixed with water the mixture boils violently
several degrees below the boiling point of the latter.
The preservative should never be applied to green timber nor when the surface
of the pole is wet from rain, snow or frost, or is frozen.
POLE-LINE CONSTRUCTION 49
The tops of the poles and the places where the brackets and braces are to be
attached should also be treated with two coats of hot creosote, and the same is true of
the butts of braces and the slanting top which is to rest against the pole.
A convenient outfit for brush treatment consists of a 5-gal. or 10-gal. can or iron
pot, a 3-gal. pail, i-gal. dipper, a 4-in. or 5-in. wire-bound brush, and a thermometer.
A small-sized, galvanized-iron wash-tub has been used with success in some places as
a vessel in which to heat creosote oil.
Section 54— Length of Poles
The standard pole is 22£ ft. long, and this dimension will be used in all but special
cases. When for any reason non-durable poles must 'be used without preservative treat-
ment, the standard length will be 25 ft. and no shorter poles may be used without
specific authority from the district inspector.
Poles shorter than 22^ ft. may be used, with the approval of the district inspector,
provided the standard length is not available, or, for some reason, is undesirable.
When a line crosses solid rock, and when it would be cheaper, the use of 2-in. or 2^-in.
wrought-iron pipes for short-length poles should be considered, notwithstanding their
liability to rust. Such poles may be fitted into drilled holes, thereby making blasting
unnecessary. There are several forms of commercial brackets and pins which, by the
use of a little ingenuity, may be set into the top of these poles or fastened to the side
by carriage bolts.
Poles longer than 22£ ft. may be used: —
(1) Where the spacing of the poles is such that the required sag in the line would
bring the wire too close to the ground.
(2) Where the underbrush exceeds 10 ft. in height. Use poles that will keep the
lowest wire at least 4 ft. above the highest brush at the middle of the span.
(3) Where snow is likely to drift to depths exceeding 10 ft. use poles that will
keep the lowest wire at least 2 ft. above the maximum height of the drift at the middle
of the span.
(4) Where it is necessary to grade the line to overcome abrupt changes in level.
For example there should not be an abrupt change from a 22|-ft. pple to a 45-ft. pole.
Instead after a 22^-ft. pole place a 30-ft. pole and then complete the change by using
poles of gradually increasing length until the 45-ft. length is reached.
(5) Where the line crosses wagon roads or railways. Use poles that will allow a
clearance between the lowest wire and the road-bed of at least 16 ft. above a road and
25 ft. above a railway, measured from the middle or highest point of the road or track.
Greater heights must be maintained if required by provincial laws. (See "Cross-
ings," Section 66.)
(6) Where necessary to cross over instead of under other poles. (See "Cross-
ings," Section 66.)
(7) At the ends of long spans (more than 500 ft.) across rivers and canyons.
Special poles or construction, approved by the district inspector, should be used.
Poles shorter than 22£ ft. may be used: —
(1) On short lines where the standard length pole cannot be readily secured.
(2) When stubs of durable species or treated with creosote are employed.
Before using short poles the approval of the district inspector must be secured.
No pole less than 18 ft. long or 5 in. in diameter at the top may be employed.
Section 55 — Erection of Poles
1 — DISTRIBUTION OF POLES
In distributing poles along a line the heaviest ones should be selected for use on
curves, at corners, at the ends of long spans, and at terminals.
79211—4
50
METHODS OF COMMUNICATION FOR FOREST PROTECTION
2 — SPACING
On straight sections poles should be set 176 ft. apart, which is equivalent to 30
poles per mile. For a grounded line, carried on poles, the distance apart, under
favourable conditions, may be 200 ft., or about 26 poles to the mile. Changes in
the direction of a line should be made gradually by spreading the curve over as
many poles as possible, raking each pole outward to offset the strain. On curves and
corners where the pull is from 10 to 30 ft., the pole spacing should be reduced to
100 ft. Where the pull js more than 30 ft., the turn will be made on two poles,
approximately 100 ft. apart, with equal spacings in the adjacent spans on either side.
At right-angled corners the length' of the section on either side next to the corner
pole should not exceed 100 ft.
Where it is necessary to make a span of from 200 to 300 ft., the adjacent sections'
should be 100 ft. in length. Spans of from 300 to 500 ft. should have two sections
of 100 ft: on each end. For spans of more than 500' ft. special construction is
required.
Where the line crosses solid rock, the length of spans may be increased v,p to
300 ft. to avoid the expense of blasting holes. When it is necessary to blast many
holes, special construction may be d'esirable, and the matter should be taken up with
the district inspector.
Abrupt changes in the level of the wire should be avoided. Poles1 shoald be
set on either side of a high or low point, using long poles, if necessary, to obtain
the desired clearance in the span. In crossing a ridge or ravine, for example, it is
better to space the poles so that one is set on each side of the ridge or ravine rather
than to set a pole on the crest or in the bottom.
3 — DIGGING HOLES
On straight sections holes should be vertical, uniform in siz<e from top to bottom,
and at least 6 inches larger in diameter than the butt of the pole. This will permit
the earth to be evenly tamped around the pole for the total depth of the hole. In
general, the depth of holes for various sizes of poles should be that shown in the
following table. On curves or in soft soils, however, holes should be at least 6 inches
deeper than the figures given.
TABLE B— SIZE OF HOLE FOR DIFFERENT LENGTHS OF POLE
Over-all length of pole
Depth of hole
Over-all length of pole
Depth of hole
In earth
In rock
In earth
In rock
18
ft.
4
4
4£
5
ft.
3
3
31
4
ft.
35...
40
45.
ft.
6
6-1
6|
ft.
?
5
22| - :
25 '...
30 .
On a hillside the depth of a hole should be measured from the lowest side of
the opening. Where the hillside is so soft that the pole may possibly " kick out,"
the depth of the hole should be determined by the foreman.
Where it is not possible to dig the required depth, the hole should be blasted.
If this is not feasible, the pole should be securely braced or guyed.
4 — ATTACHMENTS TO POLES
Standard brackets with insulators and all other equipment which is to be
Attached to the pole should be put in place before the pole is erected.
POLE-LINE CONSTRUCTION
51
Loco f /on of go/van fzecf
j iron po/e steps where
required
Fig-. 9 Pole-steps
0/VCUf?VES/?UO COtf/VEftS
Fig. 10 Location of brackets on pole
79211— 4J
52 METHODS OF COMMUNICATION FOR FOREST PROTECTION
(a) Pole-steps. — Steps should be used on all poles over 35 ft. high or to which
telephone apparatus, such as switch -boxes and test-stations, are attached. The steps
are of galvanized iron, 1% in. by 9 in. They should be driven alternately into the
opposite sides of the pole, parallel to the direction of the line, and spaced 18' in. on
centres. The line of the steps1 should be parallel to the centre of inc.- poles.
(ty Glass insulators. — Glass insulators of the kind ki^own as "regular pony
long-distance type", weighing approximately 14 ounces each and conforming to the
specifications given in Appendix E, should be used on ail lines built of No. 9 wire
when strung on poles. No. 9 pony glass insulators may be used for all lines built of
No. 12 wire strung on poles.
(c) Brackets. — On a one-wire line the brackets should be placed on the same side
of all poles, except that at corners or curves they should be on the side of the poles
away from the centre of the curve, so that the line wire will pull them against the
poles. Brackets should be nailed to the poles with one 6-in. and one 4-in. galvanized-
iron wire nail. For one-wire lines the top bracket position will be used. It is not
necessary to shave the pole at the place where the bracket is attached.
On straight sections of a two-wire line the brackets should be on opposite sides
of the poles, but on curves both brackets should be on the side of the pole away from
the centre of the curve (Fig. 10).
As an additional safeguard whenever a line crosses the tracks of a railway, two
brackets with insulators placed1 side by side should be .used on the first pole on each
side of the track. Where a line is attached to a large pole at a sharp corner two
brackets slightly separated will be used, in order to keep the line wire clear from the
pole.
(d) Lightning-rods. — Lightning-rods should be placed on poles before they are
set. In ordinary situations a rod should be placed on every tenth pole.
In exposed, mountainous regions, or where the line crosses mountain ranges or
divides, a rod should be placed on every fifth pole. It should be the same kind of
wire as the line and long enough to reach from 6 in. above the top of the pole to
about 3 ft. below the bottom. The upper end of the wire should be bent back about 3
in. from the end and given several turns about itself; the lower end should be made
into a small coil of three or four turns, 5 or 6 in. across, at the bottom of (not round)
the pole. The rod should then be attached to the pole with 2 in. staples at intervals
of 3 ft. at a point one-fourth the distance around the pole from the bracket, running
in a straight line to the ground, the upper end1 projecting about 3 in. above the ridge
of the pale. The wire coiled at the bottom should be bent into place or stapled at the
bottom of the pole so that the latter, when set, will rest on the coi-ls.
After the pole is set and the line wire attached, an inspection should be made to
make sure that there is no contact between the lightning-rod wire and the line wire.
Lightning-rods are not necessary in tree-line construction.
5 — SETTING POLES
On straight sections poles should be set vertically.
Ori curves or at corners the poles should be placed so that they will incline
outward from the centre of the curve. (Fig. 11).
When the pull is less than 5 ft., the rake should be about 10 in. (Fig. 11) ; with
a pull of from 5 to 10 ft. 15 in. ; and with more than 10 ft., about 25 in. These figures
apply to the top of the pole after it has been set and before the line wire is attached.
Warped or crooked poles should be set so that the crookedness will offset the pull of
the line wire at the ends of long spans or on curves or corners. No attention need
be paid to the possibility of the line wire changing the amount of rake. Thes>? speci-
fications are approximate and may be exceeded without harm. Rake is sorietimes
necessary even though the pole is braced or guyed.
POLE-LINE CONSTRUCTION
53
Poles should be set with the roof ridges at right angles to the line wire, except
when cross-arms are used or when it is probable that they will later be used, in which
case the ridge will parallel the line. The bracket should be exactly at right angles to
the line and in the proper position to prevent the line wire from touching the pole
X=/7 MOUNT OF RAKE'
TO BE PROW D ED ON
CURVES AND CORNERS
Pig1. 11 Definition of rake
POLE
POLE
THE PULL OA/ CORNER POLE A EQUALS D/MEM5/OU X
MEASURED O/V GROUMD L/A/E USE 5 AM E METHOD
DETERM/M/MG PULL OA/ EACH POLE /M /?
Fig. 12 Definition of pull
54 METHODS OF COMMUNICATION FOR FOREST PROTECTION
6 — FILLING AND TAMPING
In setting a pole it should he " trued " and held in position with pike-poles until
firm, the dirt being filled in evenly around it and thoroughly tamped as the filling
progresses (Fig. 13). The coarse soil or gravel should be put in last. The filling ean
be done by one man, and the tamping by two men. After the pole is set and the hole
filled, about 6 in. of earth should be closely packed around the pole above the ground.
Poles set in solid rock should have rock fragments firmly wedged in around them.
Fig. 13 Setting a pole
Section 56 — Bracing and Guying
The use of braces and guys is obviated in many cases by a proper amount of rake,
but either bracing or guying will be necessary in the following cases : —
(1) On any pole oil a curve or at a corner where the pull exceeds 30 ft.
(2) On poles at each side of a crossing over roads and railway rights of way.
(3) On the two end poles of spans between 300 and 500 ft.
(4) On the poles at either end of spans above 500 ft.
(5) On very steep slopes. Anchor guys may preferably be used in these cases,
or a head guy from the to-p of one pole (below the lowest bracket) to the base of the
pole next above it.
(6) On alternate poles in exposed positions.
(7) On poles in swamps or on loose ground (where necessary.)
(8) On poles on both ends of high-tension transmission line crossings.
(9) On the first and last poles of a line.
1 — 'BRACES
Braces (Fig. 14) should be at least 8 in. in diameter at the butt end, cut slanting
at the top to fit close to the pole but the pole itself should not be cut. They should
POLE-LINE CONSTRUCTION
55
be set at least 2£ ft. in the ground — 3£ ft. would be better if too much difficulty is not
encountered in digging. The distance between the brace and the pole, as measured on
the ground, should be not less than one-half of the height of the pole above ground.
The bottom end of the brace should rest on a flat stone or piece of log or plank. After
boring a £-in. hole through both the brace and the pole just above the point where the
bottom edge of the brace touches the latter, the brace should be bolted tightly to the
pole with a f-in. galvanized-iron bolt, using galvanized-iron washer, 21-in. square
and tc-in. thick under both the head of the bolt and under the nut.
Do no? cuf or notch ~ff>e //ne po/e-
Sroce po/e shou/d ' 6e ~f/tfe<
fo //ne po/e
Washer-
Fig1. 14 Method of bracing
2 — GUYS
(a) Anchor Guys. — Anchor guys (Fig. 15) should be made of two pieces of line
wire (No. 9 B.W.G.) twisted together, and, if possible, of sufficient length to reach from
the bottom of the lowest 'bracket to a point on the ground at a distance from the
bottom of the pole equal to the height of the bracket above the ground1, but under no
56
METHODS OF OOMMUNICATION FOR FOREST PROTECTION
condition less than 8 ft., with enough additional length to allow one end to be passed
through the eye of a standard half-inch, galvanized-iron guy rod, the other to be
wrapped twice around the pole, and both, secured.
When a guy has been prepared, one end should be wrapped around the pole twice
and stapled, the loose end beinig secured by wrapping not less than six times around
the wire, using a pair of connectors or pliers. An anchor log should then be placed
in the ground with a guy rod passing through it, the eye of the rod projecting above
the ground. One of a pair of pulley blocks should then be hooked into the eye and
the other fastened to a Buffalo grip or a medium-sized Haven clamp attached to the
guy wire. The latter should then be pulled to the required' tension and the end looped
through the eye and secured by not less than six wraps (Fig. 15), after which the
pulley blocks and Buffalo grip can be removed.
The size of the anchor log will usually be determined by the depth below ground.
If the depth of the excavation be 4£ ft. the anchor log should be 4 ft. long by 5 in. in
diameter; if the excavation be 3-| ft. deep the anchor log should be 5 or 7 ft. long by
8 or 6 in. in diameter.
Wof fess-fhon 6
METHOD Or GUY/ KG
X*- When X equals 4'/i -feet- use anchor /og 4ft et-/onobyS/n cf/ameie>
- * • 3& - - « / -*• • •> - 8 . •
\pr7 - - 6 - •
Two wraps
oround-fhe
po/e
Cra/van/zed iron rtuf and sefuore
•asr>er on end1 of guy rod
Fig. 15 Method of guying
If guy rods are not available, the guy wire should be wrapped around the anchor
log. This is temporary construction, as the guy wire will rust and break.
When a guy is used on a public highway or street in a city or town, a guard should
be used to make it readily visible. For this purpose it may be boxed up to a height
of 6 ft. above the ground, or a sapling about 3 in. in diameter may be wired to it.
This protection is also desirable where guy wires are necessary on open meadows, etc.,
frequented by men or stock.
(b) Tree guys. — If there is a live tree of large diameter nearby, the guy wire may
be fastened to it instead of to a buried log. Hardwood slats should be used between
the guy wire and the tree to prevent injury to the latter, as in Fig 33.
POLE -LINE CONSTRUCTION
57
(c) Rock guys. — A home-made iron eye-bolt 1 inch in diameter and not less than
18 in. long may be used' for anchoring a guy wire in rock. The angle formed by the
guy wire and the shank of the bolt should not be more than a right angle (Fig. 16).
The bolt should not be near the edge of the rock or ledge.
(d) Guying across roads. — If a guy wire, as ordinarily placed, would interfere
with traffic on a road, a stub should be used (Fig. 17) to provide proper clearance. The
stub should be stayed with the standard guy rod and anchor log; or if this is not-
possible, braced with anchor logs underground, as shown for the pole in Fig. 18.
_ strands #9 B.W.6. galvanized /ro/
w/ re fwisted together^ or four stranc
" 12 B. W G (shown as single w/re
to simplify ///ustrat/on )
Not Jess than 6 wraps
I inc-h diameter iron rod not /ess
than /8 inches //? lengthfdepending
on nature of roc k
Do not locate near
the edge of the rock
Fig. 16 Rock guy bolt
3 — SELF-SUPPORTING POLES
Where conditions prevent the use of any other method of guying, and especially
in swampy soil, the poles should be braced with anchor logs, >as illustrated in Fig. 18.
The problem of supporting poles in muskegs is often a difficult one. Where
ordinary methods of single bracing or guying will not suffice two or even four brace?
may sometimes be necessary in addition to anchor logs placed as shown in Fig. 18.
4 — TRIPODS
The difficulties encountered in supporting poles in muskegs are often increased
by unusual soil conditions which make the digging of holes very costly. Some success
has been met in the employment of tripods instead of poles in crossing such muskegs.
These tripods are constructed of peeled poles having a butt diameter of 5 in., top
diameter of not less than 3 in., and a length of 22 to 24 ft. Lodgepole pine is the most
suitable material, but spruce, tamarack, or jack pine may be used. Each tripod con-
58
METHO'DS OF OOMMUNICATfON FOR FOREST PROTECTION
sists of two 22-ft. and one 24-ft. pole and these poles are wired together through
holes bored 21 ft. from the butt end so that they may be raised or lowered at
will. The longer pole thus projects 2 ft. beyond the other two and from it the line
wire is suspended in a split tree insulator. The butts of the poles are not set in holes
Fig. 17 Method of using guy stub
'ill
r=~ s-7U
Grouncf
/?bouf/-fo<.
3p
^
&
L/n&
pN^lli^U^i
- c//'omefe/~ 6
/nches -fo /O/nches
mef/iod of ground orac/ng may be
L/secf
for po/es or guy &fubs when nofposs/b/e
/o anchor fr/e
Fig. 18 Method of ground bracing
but are set directly on the ground surface, and to prevent them sinking into soft soil
a 5-ft. cross-log about 4 in. in diameter may be spiked or wired1 to the lower end of
each leg.
POLE-LINE CONSTRUCTION
59
Fig. 19 Tripod line supports
Section 57 — Line Construction
1 — LINE MATERIALS
Iron wire is divided into three grades: Extra Best Best, Best Best, and Steel.
The Extra Best Best (E.B.B.) wire possesses the highest conductivity, but the lowest
tensile strength. It is designed for use on the main lines of telegraph companies, and
by telephone companies where a wire of high conductivity combined with strength and
toughness is required. The steel wire is made from a special grade of material. It
is the lowest in conductivity but highest in tensile strength. The Best Best (B.B.)
wire, which possesses intermediate qualities, is more generally used than the others on
medium distance circuits by telephone companies and for railway work.
The following table gives the physical characteristics of these three grades of
wire : —
TABLE C— PROPERTIES OF DOUBLE GALVANIZED TELEGRAPH AND TELEPHONE
WIRE1
Diame-
Weight
Put up
Approximate breaking strength
Average resistance in ohms at
No.
ter
in
in
in pounds
68° F.
B W G
^
11 1
Wire
inches
per mile
of—
E.B.B.
B.B.
Steel
E.B.B.
B.B.
Steel
Mile
4. .
0-238
811
i
2 433
2 676
3 000
5-98
7-15
8-32
6
•203
590
1,770
1,947
2,183
8-14
9-83
11-44
8
•165
390
i
1,170
1,287
1,443
12-43
14-87
17-31
9
•148
314
\
942
1,036
1,162
15-44
18-47
21-62
10...
•134
258
%
774
851
955
18-80
22-48
26-16
11
•120
?06
A
618
680
762
23-54
28-15
32-76
12....
•109
170
510
561
629
28-53
34-12
39-70
14....
•083
99
*
297
327
366
49-00
58-58
68-18
Summary of tests bv John A. Roebling's Sons Co.
60 METHODS OF COMMUNICATION FOR FOREST PROTECTION
All iron wire should be well galvanized to protect it from the corrosive action
of the weather. (For specifications see Appendix E.) Its life is 15 to 30 years and
it has little or no wrecking value when removed.
Hard-drawn coppei\ wire' possesses great conductivity and high tensile strength
and does not deteriorate when exposed to the weather. It is therefore well adapted
for telephone lines. More difficulty is encountered, however, in obtaining good elec-
trieal joints when splicing copper wire than when splicing iron wire. Copper wire is
of particular value where unusual construction is required, such as on very important
trunk lines over 125 miles in length, on metallic circuits, etc. It lasts almost
indefinitely and has a wrecking value equal to 80 per cent of its first cost.
21 — STANDARD CONSTRUCTION
A one-wire line (grounded circuit) of No. 9 B.W.G., Best Best galvanized-iron
wire will be the standard construction on the forest reserves. No other method
ishould be used unless the permission of the district inspector is first obtained. If
the line is located outside of the reserve where there are no trees, No. 12 B.W.G.
galvanized wire may be Used, provided the length is short. Metallic circuit lines
are used only where there is outside interference, such as cross-talk, induction, or
trouble from power-transmission lines'. It is not possible to talk any farther over a
metallic circuit line than over a grounded circuit line provided the grounds of the
latter are made properly. Where the length of a line exceeds 125 miles it will prob-
ably be necessary to use copper wire. This cannot be used with swinging insulators
and will not be employed except on a strictly pole line. Where necessary, a two-wire
line (metallic circuit) of copper wire may be used.
For spans up to 500 ft. the No. 9 galvanized-iron wire should be used, except
when the circuit is of hard-drawn copper wire. For longer spans steel wire or other
forms of special construction will be necessary. No. 12 New British Standard gauge
(N.B.S.G.) hard-drawn copper wire should not be used on spans longer than 300 ft.,
nor No. 14 N.B.S.G. hard-drawn copper wire on spans longer than 200 ft. If the
circuit is of No. 12 N.B.S.G. hard-drawn copper wire and it is necessary to make
spans longer than 300 ft., No. 8 N.B.S.G. hard-drawn copper wire should be used
for the spans from 301' to 500 ft. If the circuit is of No. 14 N.B.S.G. hard-drawn
copper wire and it is necessary to make spans longer than 200 ft., No. 12 N.B.S.G.
hard-drawn copper wire should be used on spans from 201 to 300 ft.
3 — CAUTIONS
Great caution must be used during lightning storms'. While lightning is being
discharged in the vicinity of the work, and as long as there is any danger from this
source, no line wire or any wire electrically connected .should ~be handled or touched.
4 — STRINGING WIRE
There are several satisfactory methods of removing the wire from the reel, and
which one to use will be determined by the conditions in each particular case. A
man familiar with the location of the line and with the transpositions should be in
charge of the Unreeling of the wire. In paying out the wire care should be taken
to place it on the proper side of poles or trees, in order to avoid cutting it. Splices
should be as few in number as possible.
When the conditions permit the use of a wagon, the reel may be placed in the
back and the wire laid upon the bracket? as fast as the wagon proceeds.
Another method is to have the wire pulled out by a horse, either with a rope
that can be released instantly, between the ends of the wire and the traces of the
horse, or by tying the end of the wire to the horn of the saddle, with a man watching
the reel. Where the line is very crooked the reel should be placed at less1 than one-
half mile from the starting point.
POLE-LINE CONSTRUCTION
61
Instead of using a wagon or horse, the wire may be unreeled by three men, one
of whom should be stationed at the reel to see that the wire is not paid out too fast
and to signal in case it becomes kinked or tangled.
Another method in forest reserve work is for two men to carry the reel, paying
out the wire as they go. This method only should be used in stringing copper wire,
as this wire should never be dragged on the ground.
Wire should not be paid out from a coil held by one man, since it comes off badly
twisted and? is likely to kink. Always use a reel.
Hard-drawn copper wire must be handled much more carefully than galvanized-iron
wire. The coil should not be thrown from a wagon to the ground. Before commenc-
ing to unreel it, the first 15 or 20 loops of the coil should be carefully lifted by hand
to guarantee that there are no " crossovers." Hard-drawn copper wire should never
be dragged on the ground while being strung. If a wagon cannot be used1 to carry
the reel, it should be carried by several men.
Care must be exercised when starting to unreel a coil to see that the outer end
of the wire is taken off. This end is generally indicated by having attached to it a
small tin tag on which the weight of the coil is stamped. The pay-out reel handled by
the supply houses is of hardwood bound with iron straps. Its weight often precludes
its use on lines following trails land through timber. A home-made reel is much
lighter and less expensive. This consists of two parts, a support and the reel proper
(Fig. 20).
Fig. 20 Home-made reel
The support is made of two 2-by-4-in. pieces AA, each 5 ft. long and held 2 ft.
apart by two cross-pieces BOB of 2-by-4-in. stuff, nailed between and 1 ft. each side of
the centre of the long pieces. Midway between the long pieces and fastened to the
cross- pieces is a 2-by-6-in. stick C. To secure greater rigidity, a 2-by-4-in. stick D
is mitred to fit from the centre of one side to the centre of one of the cross-pieces.
At the centre of stick C a block 6 in. square and 1 in. thick is attached, and
through its centre and through stick C a f-in. hole is bored. Around this hole on top
of the block a 2-in. irooi washer is attached with screws, the heads of which are well
countersunk. A bolt E, 14 in. by | in. with square head is then inserted in the
hole in C from below, and held in place by countersinking the square head on the
underside of C and nailing a small block F over it. The reel is made of two pieces
of 2uby-4-in. stuff, preferably Douglas fir or some other strong wood, GG 2 ft. 9 in.
long and mortised in the middle to form a cross. After these have been fitted together
a 1-in. hole is bored through the centre and a piece of 1-in. iron pipe H, 9 in. long and
threaded for 2 in. at the end is screwed firmly into 'this hole. On the underside
around the hole a 2-in. iron washer is fastened to act as a bearing. Nine inches from
the centre on each arm G a f-in. standard K, 18 in. long and shaped as illustrated, is
62
METHODS OF COMMUNICATION FOR FOREST PROTECTION
set upright and held in place by two nuts N, one on each side of the arm. Care must be
taken to see that these standards do not project below the arms more than the thick-
ness of the lower nut. The portion threaded should equal the thickness of the arm
plus the thickness of the two nuts. The cost of the whole apparatus is so small that
after the iron fittings are removed' the rest may be discarded, if necessary, when the
work is completed.
No more wire should be strung out than can be put up and tied in during one day.
Special care should be taken not to allow the wire to lie across trails or roads where
it might be run over by vehicles or trampled by animals. Kinks or nicks made in
this way may weaken the wire sufficiently to cause it to break as soon as a little
strain is put upon it, or when it contracts in cold weather. All kinks should be
straightened before the wire is stretched. If the kinks or nicks are bad' they should
be cut out and a splice made.
5 — TRANSPOSING LINES
By transposition is meant changing the lo'cation of a wire from one side of the.
pole to the other (Fig. 21). This is1 done to overcome the effects of outside inter-
ference existing in lines which are close to or parallel with high-tension transmission
lines, and wires which are on poles carrying other wires-.
Brace of brocket
on reverse s/c/e
ofsorne /eve/
ELEV/3T/OM
PL/? A/
Fig. 21 Transposition of wires, metallic circuit
When building a metallic circuit, the wires should be transposed once every mile.
Where the line is exposed to induction, cross-talk, power wires or electric-light wires,
the line wires should be transposed at least every tenth pole. In transposing telephone
lines, the wire on the left should always cross over, never under, the wire on the right,
and without touching it. On a bracket line the transposition can be made very easily
by changing the location of the brackets on the pole, as shown by the upper diagram in
Fig. 21. When a cross-arm is used, transpositions can best be made by using a standard
two-piece transposition insulator. Transpositions should be arranged for at the time
the wire is unreeled; the left-hand wire crossing over on top of the right at the point
where the line is to be transposed.
6 — SAG ALLOWANCE
The stresses in the telephone wire undergo changes with variations in temperature,
thus making it necessary to provide for the extreme variations in wire length in each
POLE-LINE CONSTRUCTION
63
span. The sag in the wire at the time it is made fast to the brackets should corre-
spond to the temperature at that time.
TABLE D— SAG OF A No. 9 B. W. G. GALVANIZED-IRON WIRE IN A POLE LINE
Length of span in ft.
Sag at temperature indicated in degrees F.
+ 100°
+80°
+60°
+30°
+ 10°
-10°
-30°
75...
100
115
130
150
ft. in.
4£
7"
9
11
1 2
1 6
1 10|
3 3£
4 7
6 6
8 0
10 0
12 6
ft. in.
3
5i
8J
11*
1 3
1 7
2 10
4 1
5 6
7 0
9 0
11 0
ft. in.
"'2
4!
5|
9
1 0
1 4
2 5|
3 6£
4 11
6 6
8 0
9 6
ft. in.
2
3i
5i
9^
1 0
1 11
2 9
3 10
5 0
6 6
8 0
ft. in.
n
3
3*
4*
6
8
10|
1 8
2 5^
3 5
4 6}
6 0
7 6
ft. in.
n
2|
3
4
5
7
9
1 5^
2 H
3 0
4 4
5 6
7 0
ft. in.
1
2
2i
3*
4|
6
8
1 3
1 10
2 7
3 7
5 0
6 0
176..
200
260
300 .
350...
400
450
500
NOTK. — If a strong wind is blowing, the sag value should be increased. Interpolate for temperatures
and spans not given. When any other size than a No. 9 B. W. G. wire is used, it will be necessary to com-
pute the sag required. Instructions for doing this will be furnished by the district inspector.
Sag may be handled in the following manner: After a half-mile reel of wire has
been pulled out, linemen, who follow, carry the wire up each pole 011 their shoulders
and place it between the bracket and the pole. When this has been done over the entire
half mile, the line is stretched by means of a Buffalo grip and stretcher-block until it
is taut, or until the two or three linemen who are on the poles along the half-mile
stretch pass along the signal to stop. About two minutes' rest is then required for
the line wire to " creep " along the entire distance. It should then be loosened or
stretched tighter, according to the signals of the men on the poles, who can sight from
the bracket of one pole to the brackets of the adjacent poles and determine when the
proper amount of slack has been provided,
7— TYING IN WIRE
On straight lines the wire should be tied to the inside of the insulator, so as to
bring it between the insulator and the pole. On curves and corners the wire should be
tied to the insulator on the outside, so that the strain will be against the bracket and
the pole.
On pole-line construction the tie wire (the wire used to fasten the main line to
the insulator) should be of the same size as the line wire. The method of tying wire
to a glass insulator is shown in Fig. 22.
In making the tie great care should be exercised to avoid twisting the wire so
tightly that the main line will be burned.
Linemen should be cautioned against nicking the line wire in making ties,
especially when this is hard-drawn copper. The latter should always be tied by hand.
Pliers, connectors1, or other tools should be used only with iron wire. Linemen should
also be cautioned against leaving the endte of the tie wire protruding, lest through
twisting of the pole a contact be made.
(a) Tying galvanized-iron wire. — There are two methods of tying galvanized-iroii
wire. The regular tie (Fig. 22) should be used on all poles except where there are
sharp dips or changes in level in the line .wire, or in crossing railway rights of way,
or on spans from 250 to 500 ft. in which cases the " figure 8 " should be used (Fig. 23).
64
METHO'DS OF COMMUNICATION FOR FOREST PROTECTION
When the work of stringing wire on a pole line is stopped for a short time, or at
the end of the day, the last tie put on will be a figure 8 tie. The line wire will then be
continued over the bracket of the next pole without being tied, and brought down and
anchored to the butt of the next farther pole by means of a Buffalo grip and either
stretcher-blocks or a snub.
/Vof /ess l/ia/i~3 c/ose
wraps
TIG w/re to be of
The same s/ze
fie wire
Fig-. 22 Method of making regular tie for iron wire
Of
Ga/i/ /rorr //ne w/re
ffraff 3 c/o^e wraps
7/e w/rie /o be. same,
fr/'rrd 0,5 //'ne.
Fig. 23 Method of making " figure 8 " tie for iron wire
The figure 8 tie is made by first bending the tie wire into a horseshoe shape just
large enough to fit the insulator, putting it over the line wire (first position, Fig. 23),
which has been placed in the groove of the insulator, and then bringing the two ends
POLE-LINE CONSTRUCTION
65
of the tie wire around the insulator in opposite directions and wrapping them tightly
around the line with not less than three wraps, as close together and as tight as
possible, using pliers or connectors for the purpose.
The line should be dead-ended (Fig. 24) at such places as the first or the last pole
on a main or branch line, or at a station.
(fr) Tying hard-drawn copper wire. — All tie wires for hard-drawn copper wire
should be of the same size as the line, 'but of annealed (soft) copper. >Soft tie wires
may be purchased in bundles or they can be made by cutting up the line wire and
heating and then cooling it slowly to make it less brittle. Care should be taken not
to heat the wire too hot, so that it pits, or to cool it too quickly. Hard-drawn copper
wire is dead-ended by the use of a half-length, double-tube copper sleeve.
The regular tie for copper wire (Fig. 26) should be used in all cases except where
a figure 8 tie is required (Fig. 27).
i less than Sc/ose. wraps
Fig. 24 Method of dead-ending iron wire
Ha •// length x/eeve - /%>
Fig. 25 Method of dead-ending hard-drawn copper wire
8 — SPLICING WIRE
The standard Western Union joint (Fig. 28) or the standard three-wire splice
should be used for uniting galvanized-iron wire, and the standard double-tube copper
79211—5
66
METHODS OF COMMUNICATION FOR FOREST PROTECTION
sleeve for hard-drawn copper wire (Fig. 29) ; galvanized-iron sleeves should not be
used. Copper sleeves should not be used for splicing galvanized-iron wire, because
the resulting corrosion of the latter results ultimately in a high-resistance joint which
may become the equivalent, from an electrical standpoint, of several miles of extra
line.
Soft' copper t/e
as
A/of /ess Than 5 fusris
.v _
Fig-. 26 Method of making- regular tie for hard-drawn copper wire
When copper sleeves are used for joining hard^drawn copper wire, they should be
twisted not less than three nor more than four turns with a pair of reversible con-
nectors of the No. 309 type. The ends of the wire" should project approximately 1 in.
from the end of the sleeve before twisting. After the sleeve is twisted the protruding
ends of the wire should be cut off not closer than \ in. and bent back slightly on the
sleeve.
In ordering sleeves it is necessary to specify the size of the wire for which the
sleeve is required. In making joints every precaution should be taken not to nick the
wire, whether galvanized iron or copper.
POLE-LINE CONSTRUCTION
67
//o/t/ dnzwrr
copper f/'e wire
same size as line w're
n of f/e wire
A/oT/ess thorr & Turns
Fig. 27 Method of making "figure 8" tie for hard-drawn copper wire
A 'of /ess fharr 3~ c/ose wraps
Fig. 28 Method of splicing iron wire (Western Union joint)
DouJ)/e. Tube, coppes-js/eere before, usfrrg
S/ecve. offer using.
Tivtsteci 3 to 4- fuJ/ turns ctepzn dirty on its /ength
Fig. 29 Method of splicing hard-drawn copper wire
79211— 5 &
CHAPTER TX
TKEE-LINE CONSTEUCTION
Section 58 — General Principles
With a telephone line passing through a heavy stand of timber, the possibility of
trees falling across the line makes it essential that the line wire should be able to give
way without breaking. The rigidity so necessary for standard pole-line construction
is therefore undesirable and even inimical to proper tree-line construction.
The. tree-line method is generally used when poles are scarce or inaccessible, when
ground conditions are unsuitable to the setting and maintenance of poles, or where
there is not enough money available for the construction and maintenance of a
standard pole-line.
The essential features of the tree-line method are the use of the split insulator
and a suspending wire support. The former allows the line wire to draw through it
when there is a pull from one side; the latter permits the wire to be attached 'to the
tree itself.
Metallic-circuit tree lines are seldom used. Short circuits, resulting from broken
wire ties and from trees falling across the lines, make this method of construction im-
practicable under ordinary conditions. Where the danger from high-voltage trans-
mission lines makes necessary the use of a metallic circuit, but other conditions make
the use of a tree line desirable, the wires should be strung on separate trees and the
standard methods of transposition followed. Under no circumstances may a metallic
tree line be undertaken without authorization by the inspector.
Section 59 — Selecting Trees and Route
Judgment and care should be used in selecting the trees to support the line, and
also in determining the tying place on each tree and the method of tying. Only sound
trees should be selected, of sufficient diameter to minimize the swaying, but large and
smooth tret^i that are difficult to climb should be avoided. The course of the line
should be varied to take advantage of trees that will lessen the cost of construction;
but if suitable trees are not available, poles should be used.
In tree lines the spans should not exceed 175 feet. If possible the average span
should approximate 100 feet, and may be shorter if necessary. The span should be
equalized, that is adjacent spans should be as nearly of equal length as possible and
no abrupt changes in length of spans should be made The crooks and turns of the
trail should not be followed unless to do so would mean more economical and better
construction. The line wire should never touch the trunk of a tree, and care should
be taken when attaching the insulators to see that the pull of the wire is away from
the tree and not against it. On side-hill slopes the line will be strung, if practicable,
below the trail, so that in case the wire comes down it will not fall on the trail.
Wherever possible avoid crossing the trail.
In selecting trees for ties two systems of alignment are followed both of which
give good results. In the first system (Fig. 30) the effort is made to select the trees so
that they follow a regular zigzag course, each tree being on the opposite side of the
right of way from the two adjacent ones. The amount of pull between adjacent trees
on the same side of the right of way should be 6 to 8 feet. The wire then forms a
zigzag over the cleared right of way and pulls away evenly from each tie tree. The
insulator, of course, is attached on the inner, or concave, side of each crook in the line.
68
TREE-LINE CONSTRUCTION
69
In the second system (Fig. 31) the line is built in the form of a series of long
reversed curves. On curves, while all insulators are on the same side of adjacent
trees the wire nevertheless pulls away from all trees on the curve. By laying out the
Fig. 3>0 Zigzag system of alignment
9
Fig. 31 Reverse curve system of alignment •
entire line in a series of reverse curves, each of six or eight spans in length, the desired
pull away from the tie trees is secured without the frequent crooks in the line
encountered in the first method.
Section 60 — Line Construction
1 — THE " Six EULES " FOR TREE-LINE WORK
For successful tree-line construction, the following six rules should be kept con-
stantly in mind: —
1 Slack wire.
2 Equalized spans.
3 Weak ties.
4 Standard installations.
5 No sharp turns in line.
6 Avoid attaching wire too high on trees.
2 — LINE MATERIALS
For tree-line work, only No. 9 B.W.G., B.B., galvanized-iron wire, or heavier, can
be successfully employed. This is true, regardless of the length of line. The strains
to which tree lines are exposed are much greater than with pole lines and no wire of
lighter weight than No. 9 will resist them successfully. Copper wire cannot be
employed at all with this method of construction. Although tree-line methods involve
the building of a very crooked line with a great deal of slack, the actual length of
wire is not thereby seriously increased. Only about 100 feet per mile of line wire need
be allowed for the normal crooks and slack of a standard tree line.
For tie wire No. 12 B.W.G.. galvanized-iron wire is employed. A mile of No. 12
wire will s make about 2,700 tie wires or enough for approximately 60 miles of line,
allowing 45 ties to the mile.
Split tree insulators and 4-in. staples, sufficient for 45 to 50 ties per mile of liner
are the only other line materials required. The latest form of split tree insulator (See
70 METHO'DS OF COMMUNICATION FOR FOREST PROTECTION
Appendix E) which, is elliptical in cross-section not only avoids several of the more
serious defects of the original circular and hexagonal types but is much heavier and
of better material, and therefore stronger. It will be standard on all Forestry Branch
lines.
3 — STRINGING WIRE
The methods given in Section 57 are also applicable to tree-line construction, al-
though the latter offers less opportunity for the use of a wagon. The same precaution
should be taken not to injure the wire. In most cases the only practicable way to pull
out the wire is by hand from a stationary reel. Where very thick brush is encountered
along the right of way it will sometimes require three or four men to pull a half-mile
length of No. 9 wire, with an additional man to tend the reel. Two men should take
the end of the wire to which a cross-bar is attached for a handle, while the others
distribute themselves along the right of way as the strain becomes heavy. It is import-
ant to remember to remove the cross-bar from the end of the wire, and to straighten
out the latter after having pulled out the coil.
A large amount of slack -should be provided. The exact amount will be determined
by the conditions, topography, etc., but, in general, each span should be given about
4 ft. The aim in to provide enough alack so that several trees may fall across the line
within a few spans without breaking the main line.
This should always be tested after the wire is up by catching hold of the line wire
between supports and pulling to the ground. It should have sufficient slack to permit
this to be done in every, span, and, where slack-holding ties are used, at least four times
simultaneously between each pair.
Under ordinary conditions the use of brackets in tree-line construction should be
avoided.
4 — HEIGHT OF WIRE
The wire should not be hung at a greater height than on a pole line and in general
should be hung about 18 ft. above the ground at the point of attachment, giving 14 ft.
at centre of span.
5 — SPLIT TREE INSULATOR ATTACHMENT
The method of making the split tree insulator attachment is shown in Fig. 32.
C and D are the insulator attachments that have given the best results. The former
uses No. 12 wire and comes loose from the staple whenever a tree falls across the line.
In such cases neither the tie wire itself nor the split insulator breaks. To make repairs
it is merely necessary to replace the attachment on the staple as illustrated in the
figure.
The attachment D involves the same principle, but uses No. 9 wire. When this is
employed it is necessary to keep only one kind of wire in stock, though the tie C is the
least expensive and the easiest to make. E shows a little stronger attachment made of
No. 12 wire which should be used in conjunction with the crosstie shown at A. All ties
should be attached to the tree by means of a 3-in. or 4-in. staple, according to the thick-
ness of the bark, about 1 in. of the staple being left protruding from the tree. A 2^-in.
post staple may be used in hardwood timber. When there is a possibility that the tree
to which the insulator is attached may be cut into sawlogs, a wire wrapped around the
tree with a loop twisted in the middle should be used instead of tne staple.
The staple should be set with its two points in a vertical plane. The split insulator
is attached to the line wire by the lineman before climbing the tree. Particular care
must be taken in forming the loop of the tie wire around the staple to see that it is
snug and that the reversed ends are left about 2 in. long and closely parallel to the
shank of the tie. A very great variation in the amount of pull required to detach this
tie can be secured by altering the shape of the loop around the staple, and if not pro-
TREE-LINE CONSTRUCTION
71
perly made it may be found that the ties pull loose under the weight of the line wire
alone. This must, of course, be avoided and the ties so made that they will not only
support the wire but also withstand the shock of falling trees up to the point where it
threatens to break the line.
Fig-. 32 Split tree insulator attachment and crosstie
6 — CROSSTIE
Fig. 32 A illustrates a complete crosstie with a No. 9 wire runing through the in-
sulator. Such >a tie should be used wherever it is desired to prevent the wire from run-
ning back after breakage of the main line. It should be made of No. 12 wire and be
from 20 to 25 in. long. This tie is usually preferable to the insulator and bracket dead-
end, in that it lessens the chance of the main line being jerked by heavy winds.
The line should be stayed at the top of hills or the beginning of steep slopes. It is
not necessary to stay it on comparatively level ground if spans are properly equalized.
The use of crossties should be avoided as much as possible. Perfect equalization
of spans will enable this to be accomplished in any but mountainous country.
7 — DEAD-ENDING
So far as is practicable lines should be dead-ended and poles set and .braced for
that purpose. One or, if necessary, two brackets set close together may be used, the
method of fastening wire being illustrated in Figs. 24 and 25. When dead-ending on
trees the bracket-and-insulator method is not desirable, but instead the No. 500 white
strain insulator attached to the tree by four to six wraps of standard galvanized strand
should be used. The tree should be protected by four shims or cleats of wood. This
method is illustrated in Fig 33.
Dead-ends should be used in the following situations: —
(1) At terminals of lines
(2) At the ends of all extra long spans
(3) At the tops of all long stretches of line, or steep slopes where the standard
crosstie is not adequate to stand the strain.
72
METHODS OF OOMMVNICATION FOR FORREST PROTECTION
8— SPECIAL TYPES OF CONSTRUCTION -
In regions where there is little timber and practically no danger from windfall
a No. 3^ porcelain knob fastened to the tree with a 6-in. spike may be found satis-
factory. It should not be used, however, without the permission of the district
•4-Cemp/ete
na stuff
No. 5 00
insu/otor
6- Short turns.
Pieces 6 wide /2"/ong 2" thick, either
sp//t, hewn or- sawed, f>n four sides of
tree. Fasten So tree with 2~5in.na//s.
Dec/of- en ding on po/es- Omif protecting
pieces and reduce fore space to 3 inches.
Seiz/ng stuff may be fastened to po/es
with nai Is, or common fence stap/es.
//eiser- dead-end a line of y eater weight
than SO ff. ofN<?.9w/re to bo//d/nq and
then dead-end on brackets and a/ass
Fig. 33 Method of dead-ending on tree lines
inspector. In this type of construction the spans should1 average about 100 ft., with
from 10 to 15 ft. of sag, according to the length of the span. A No. 12 wire should
be used to tie the main line to the insulator, using the tie indicated in Fig. 26.
This method will be found1 satisfactory only in large, open western yellow pine and
similar types where there is little windfall and almost no sway of the trees at the point
of attachment of the insulator. It should not be used for any but short branch lines
or on short, alternative routes.
The spike should be driven into the tree for almost its entire length, leaving
only about l£ in. exposed. Since the weight of the wire falls on the top of the
insulator, the strain on the tie wire is small. The lower branches of the tree should
not be trimmed1, since they tend to prevent the line from grounding when a tree falls
on it.
In some regions of excessive winds where deciduous species, such as poplar, are
used for tie trees, it has been found that the constant sway of the ties causes them
TREE-LINE CONSTRUCTION 73
rapidly to wear thin at the staple. In these situations windfall is often not very
great, and good results can be secured by tying the insulator down to a nail or
staple set below it or by abandoning the use of the staple entirely - and wiring the
split insulator tight against the tree with a loop around the tree itself. Still another
method that has proved satisfactory is to employ the tie shown in Fig. 32E, but
instead1 of making a plain loop of wire around the staple, to use galvanized-iron
wire-rope-thimbles around which to make this loop. Get the size used with iVin.
wire rope.
A similar .method can often be used to advantage in constructing pole lines
through dense istands of small, dead spruce, so common in the northern forest. In
this region it is sometimes impracticable to cut &n adequate right of way at once,
for lack of funds, but a pole line is necessary for lack of suitable tree supports.
Under these circumstances poles should be set in straight lines as for a pole line but
split insulators tied down to a spike below the wire should be employed1. All large,
dead snags should be cut, and when later a full right-of-way clearing is made the
regular bracket and pony glass insulator may be substituted.
9 — CROSSING MEADOWS AND PARKS
It muy sometimes be preferable to cross small meadows and parks instead of
making the detour necessary to the continued use of trees. Poles should ordinarily
be used to make crossings of this kind.
When not more than six or eight poles are necessary, they should be considered
as trees, and the line wire attached to each by a split insulator, allowing as much
slack as elsewhere in the line. In this way no injury to the portion of the line in
the park or meadow will be caused by a tree falling on an adjoining span. If a
large number of poles is required, the first eight poles on each side of the meadow
should1 be equipped with split insulators. For the remaining distance the standard
pole-line construction with the sag in the spans as indicated' in Table I) should be
used. Do not " stagger " any of the poles unless they are properly raked and guyed
to witbstand the strain.
10 — CROSSING KIVERS AND CANYONS
Where it is necessary to cross a river or canyon less than 500 ft. in width, n
pole should be set (do not use a topped tree) on each side of the canyon or river
and securely anchored1. Each pole should be equipped with double brackets and the
wire tied to the insulators with the figure 8 tie.
Where the span exceeds 500 ft., specific instructions should be obtained from
the district inspector before construction is begun.
11 — CROSSING DIVIDES AND BUILDING TO LOOKOUT POINTS
Two methods may be followed in constructing lines across divides and watersheds
and to lookout points.
The usual tree-line construction should be used when the timber is heavy and
such construction practicable. The line should follow a trail or road. Frequent
switch-backs may be necessary in order to get over the divide.
The line should be hung in split tree insulators, using the regular attachment
C, Fig. 32, except on trees at very abrupt changes in line direction. At such points
a tie wire similar to B or E, Fig. 32, should be used, the tie being made of single
No. 12 B.W.G., B.B., galvanized wire. This tie is lighter than the main line and
a trifle stronger than the ordinary ties (C and D, Fig. 32), and will break as soon
as more than one tree falls across the line, thereby providing all of the slack between
the tree at the turn and the acftacent trees.
74 METHO'DS OF OOMMUNICATION FOR FOREST PROTECTION
The second method will be followed when the trees are scarce or when the other
method of construction is not practicable. ' The line should be run straight up the
side of the mountain. Brackets and glass insulators should be used, and the wire
tied to the outside of the insulator with No. 14 B.W.G., B.B., galvanized-iron wire,
which is very light and will break easily. About 4 ft. of slack should? usually be
allowed for a 100-ft. span.
CHAPTER X
EMEKGENOY LINES, CONSTKUOTION AND USE
Section 61 — Use in Forest Protection
For the purpose of quickly establishing telephone communication at points not
on a permanent line, the military system of laying light insulated wires on the ground
has been adopted. The more thoroughly organized the protection staff becomes, the
greater is the need for maintaining direct communication .between all its parts.
Emergency lines serve two main purposes in forest protection, but they are also
extremely useful in general administration work on forest reserves. In protection
work they have the following application: —
(1) To connect the ends of a permanent line across a break caused by forest
fire, landslide, or other serious d'amage to the line. This is required where it is
important that the use of the permanent line continue without interruption and where
the repairs will require some time.
(2) To connect fire-camps, commissary camps, and other important points on the
fire-line or line of communication with headquarters in the rear. This is usually
accomplished by connecting the temporary camps with the nearest permanent tele-
phone line. Heliograph stations may similarly be connected with the fire-camp nearby.
In general administration on forest reserves various kinds of temporary camps
are established, all of which may require telephone connection to attain the greatest
efficiency. Emergency lines will serve to provide such connection if a comprehensive
system of permanent lines has been installed.
Section 62 — Line Construction
1 — LINE MATERIALS
The wire adopted for emergency lines in forest protection is approximately a No.
20 B. & 'S. gauge consisting of 10 strands of No. 30 B. & S. gauge hard-drawn copper
wire twisted together and insulated with a double-reverse, close serving of cotton,
waterproofed with asphaltum compound. (For specifications see Appendix E.) It
has a resistance of about 53 ohms per mile or approximately the same as No. 14
B.W.G., BB., galvanized-iron wire. Its weight is 20 pounds per mile, and its breaking
strength 48 pounds. This wire is purchased in half-mile lengths wound on wooden
spools conforming to the standard specifications. (See Appendix E.)
The only other line-construction materials required are some rolls of cotton tape
(stationers' red tape is good) or some balls of cotton package twine, and some 3-in.
wire nails.
2 — LINE TOOLS
The crew employed in laying an emergency line requires the following tools and
material : —
1 2^-in. screw-driver 1 roll friction tape
1 pair 6-in. side-cutting pliers 1 forked pole or crook-stick
1 emergency wire reel 1 ball cotton twine
1 pocket-knife for each man Supply of 3-in. wire nails.
1 hand-axe for each man
EMERGENCY LINES 75
If this equipment is not readily available the work may still be done with only the
forked pole and a heavy hunting-knife such as is described under Section 83. (See
Figs. 64 and 66).
3— WIRE CREW
A crew of two men will suffice, but more should be employed if available. One
man is required to carry the reel. The rest of the crew follow behind and place the
wire in position along the route. In some cases another portion of the crew must be
sent ahead to cut and set poles or stakes to which the wire is attached.
4 — CONNECTING TO PERMANENT LINES
A connection to an overhead permanent line with emergency wire should be
made at a pole or tree. Make bare 8; to 10 in. of the copper conductor and wrap tightly
around the line wire, after scraping the latter clean. Tape the joint to prevent slipping.
If connection is made at a tree, place a crosstie around the split insulator in the usual
manner and connect with the emergency wire outside this tie. Carry the wire down
the side of the tree or pole, holding it by tape, to a point about 12 ft. from the ground
from which it is led off to the emergency station.
5 — STRINGING WIRE
Insert a spool of wire in the reel and tighten up so that the wire will come
off freely from the underside of the spool. The reel carrier must then go ahead
with the reel strapped to his back, following the route the line is to take. Care must
be taken to see that the reel does not overrun or the wire get into snarls. The wire
must not be dragged over the ground. Under no circumstances should it be pulled
from a stationary reel, as is iron wire.
Fig. 34 Method of tying up emergency wire
One or more men must follow closely behind the reel to tend the wire. These
men should carry light forked sticks about 7 ft. long with which they place the wire
in a safe position. The only safe place for the wire is one in which it will not be
run into by man or beast. So far as possible it should be elevated above the ground
on the branches of trees high enough to be above pack animals, and where it crosses
roads or trails it must be at least 12 ft. from the ground. Do not let the wire lie
on damp ground as in crossing a muskeg, even if it is necessary to set light poles
to raise it on. Along pack- trails and roads keep the wire at least 10 ft. from the
line of traffic. Keep the wire out of water.
76 METHODS OF COMMUNICATION FOR FOREST PROTECTION
To tie up the wire to supports, use tape or cotton twine, making a barrel hitch
as in Fig. 34. Do not let the wire come in contact with nails. Hang it from- the
nails by means of the twine. Make no spans greater than 75 ft. in length and do
not allow the wire to be drawn tight, especially where fastened to the limbs of trees
as the swaying is likely to break it.
Leave the empty spools along the line at the end of each coil. Always run the
wire through the hole in the spool and place the latter well up in a tree where it
will be out of sight of passers-by.
6 — SETTING POLES
Although for the most part emergency wire will be laid directly on the ground
or looped among the lower tree branches and over underbrush, yet cases sometimes
occur where a more careful placing is desirable. This can be very easily accomplished
by using light poles for supports. These poles should be straight, trimmed clear of
branches, about 10 to 14 ft. long and 2 to 3 in. in diameter at the butt. Any species
will do. They need not be peeled! and can generally be cut immediately adjacent
to the line. Send the pole crew well ahead of the wire crew to cut, trim, and dis-
tribute poles at 75-ft. intervals along the route.
The pole-setting crew of three men follow the reel. This crew is provided with
the following tools in addition to those furnished for wire stringing: —
1 pole-axe or sledge-hammer
1 4-ft. steel bar, or pointed pipe with drive cap
With the hammer and bar two msn make the holes into which the poles can
be thrust. The third man makes a deep, downward hack in the pole at the proper
height, inserts the wire, ties it if desirable, and sets the pole in place in the hole
prepared for it, tamping it with his heel. Several crews may work simultaneously,
and with enough men cutting poles to keep well in advance of the reel the line can
be erected at a fast walk.
Section 63 — Maintenance
Maintenance is extremely important. As often as possible a man should be
sent along the wire with the forked stick to see that it is kept well elevated above
the ground among the trees or bushes. A line that is left out for some length of
time may be very much improved in this way- If the line is broken, the break may
be very difficult to find. The only safe way to locate a fault is to run the wire
through the hand until the fault is reached.
Temporary joints are best made by tying a knot in the two wires as shown in
Fig. 35. Peel off the insulation for about 2 in. on each wire and twist tightly to-
gether. Raise all joints above the ground and fasten to a pole or branch with tape.
After each season the emergency wire should be thoroughly overhauled. All
temporary joints should be replaced by permanent joints, soldered, taped, and painted
with insulating compound. Bare places in the wire should be similarly repaired, and
pieces in which the copper conductor has been injured should be cut out. Reel the
wire back on the spool evenly and tightly and store in a dry place.
Section 64— Taking Up Wire
The same reel is used as for paying out wire but is reversed and hung on the
breast instead of the back. Insert an empty spool and tighten so that it will not
slip on the crank. One or two men should go ahead of the reel and remove the wire
from the limbs and bushes and place it in the road or trail so as to expedite reeling
in. They should start some minutes ahead of the reel, and at each half-mile joint
the wire should be cut and the ends made fast to a stake, tree, or some other solid
support. The men talcing down wire must run the entire line through their hands
so that there will be no ties left for the man with the reel to release.
Fig. 35 Method of making temporary splice in emergency wire
Fig. 36 Emergency wire reel, open and folded
77
CHAPTER XI
FOREIGN LINES, CROSSINGS, AND CONNECTIONS
Section 65 — Location on Poles of Foreign Lines
When a Forestry Branch line is attached to a pole carrying a telegraph circuit,
the former should be located at least % ft. from the nearest telegraph wire. This
same clearance should be maintained between a Forestry Branch wire and any other
wire on the same pole that does not belong to the same system. Forestry Branch
lines should not be attached to poles carrying electric light, power, or high-tension
transmission lines. A grounded line should never be strung on poles carrying tele-
graph circuits or other telephone circuits either grounded or metallic. Use a metallic
line.
Section 66 — Crossings
1 — RAILWAY RIGHTS OF WAY
Railway rights of way should be crossed at right angles. All such crossings
must be made in accordance with Order No. 231 of the Board of Railway Commis-
sioners for Canada. (See Appendix D.)
2 — FOREIGN LINES
Whether to cross over or under foreign lines will be determined by the character
of their construction. If the foreign lines are well constructed and well maintained,
they should be crossed underneath at a distance of not less than 4 ft. below their
lowest wire, unless this would bring the Forestry Branch line too close to the ground.
In that case a crossing should be made over the foreign line, with a distance of not
less than 4 ft. between the lowest part of the telephone line amd the highest wire of
the foreign line. If the construction or maintenance of the foreign line is poor,
the Forestry Branch line should in every case pass overhead.
3— ROADS
If the line following a road, crosses from one side to the other, the crossing poles
should be braced., or guyed, and a figure 8 tie used. The wire should be strung at
least 16 ft. above the road, or even higher if required by provincial law
4 — CROSSINGS OVER 500 FT. IN LENGTH
Crossings more than 500 ft. in length may involve the use of steel-wire, special-
strain insulators, towers, or bridge work, and special "A" or "H" construction. Before
any construction is undertaken, the district inspector should be asked1 to prepare
proper specifications.
5 — HIGH-TENSION TRANSMISSION LINES
Contact at any point between a telephone line and a high-tension transmission
line endangers both the entire telephone system and the lives of those who use it. In
all cases when a high-tension transmission line is to be crossed by a Forestry Branch
telephone line, instructions should be obtained from the district inspector. Trans-
mission lines should be given as wide a berth as possible. If it is necessary to run
close to one, pole-line construction should be used.
j
78
FOREIGN LINES AND CONNECTIONS
79
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80 METHODS OF COMMUNICATION FOR FOREST PROTECTION
Transmission lines should always be crossed at a right angle. Unless the dis-
trict inspector specifies otherwise, or unless the transmission company has provided
special and safe protection, the crossing will be made as follows: Dead-end the tele-
phone line on each side of the transmission line, at least 150 ft. from the cross! im.
and brace or guy the lasst poles. The actual crossing should be made underground
by means of an extra heavily insulated, rubber-covered, braided, and weather-proofed
No. 14 B. and S. copper wire run through a 1-in. iron pipe, starting at a point on
the pole about 8 ft. above the ground. The joints in the pipe should be made water-
tight by the use of red lead, and1 an inverted "U" attached to the top of each pipe,
so that rain-water cannot follow the wire. The rubber-covered wire should extend
up the pole and be connected to the line wire. In. crossing with a metallic circuit both
wires may be run in the same pipe. This method is illustrated in Fig. 37.
If considerable blasting would be required to put the iron pipe underground
below the frost line, it may be laid across the surface of the rock, providing it is
covered with an earth embankment to a depth of 2 or 3 ft.
If permission is requested for a high-tension transmission line to cross an existing
forest reserve telephone line, the Director will require that the transmission line be so
constructed as to provide safe and approved protection for the Forestry Branch line.
Where the telephone line is exposed to voltage in excess of 5,000 volts Order 231 of the
Board of Railway Commissioners for Canada for overhead crossings of electric-light
and power lines will be used as a basis for determining suitable protection. (See
Appendix D.)
6 — SUBMARINE
In many regions, particularly in the eastern forests of Canada, the necessity
for crossing wide bodies of water with telephone lines arises with great frequency.
•Often many miles of aerial construction can be saved by a comparatively short sub-
marine span. If properly laid with suitable material, submarine lines involve almost
no maintenance charges. Cost of installation is usually very low. Against these
advantages, however, there are certain serious objections to submarine lines which
must be fully considered.
A suitable conductor, that may be depended upon to give uninterrupted service
is likely\ to be very costly, particularly where there is any current in the body of
water to be crossed.
A break or leak in a submarine cable causes a complete interruption of the
service and it is impossible to make temporary emergency repairs as with land lines,
but the cable must be raised, often at considerable expense, and permanent repairs
made before service can be resumed.
A submarine cable has a very great electro-static capacity, many times greater
than the same length of overhead wire, and the practical result is that a mile of such
caole is equivalent to approximately 2.3 miles of well-built, standard land line. The
use of even short submarine spans, therefore, in long land' lines must be carefully
considered, not only from the standpoint of first cost and maintenance but also from
the standpoint of their effect on the operating efficiency of the line.
No submarine cables shall be purchased unless authorized by the Director^ and
on specifications furnished by him, and no such cable shall be installed until the
proposed site has been inspected and approved by the district inspector. As sub-
marine cables for still-water spans over one-half mile in length, or for spans of any
length in water having a perceptible current, may have to be manufactured to special
specifications, field officers will be expected to report all such cases to the district
inspector at least one year before construction is contemplated. In reporting, state
length of water-span, character of current, if any, nature of bottom at each shore
and in the middle of the span, depth of water at intervals from shore to shore, annual
variation in water level, if any; and state whether or not the water is contaminated
with industrial acids or other corrosive substances or is salt or brackish. A map of
FOREIGN LINES AND CONNECTIONS 81
the proposed crossing site, showing the contour of the shore on each side for 500
•ft. from the water-line, and a profile of the body of water along the proposed line
of crossing should accompany each report.
Submarine telephone cables may be roughly divided into three classes:
(1) Rubber-covered copper wire protected by two or more heavy servings of jute
impregnated with waterproofing compound.
(2) Rubber-covered and taped copper conductor, inclosed in a heavy lead sheath
either bare or juted.
(3) Rubber-covered, taped, and juted copper conductor inclosed in an armouring
sheath of galvanized-iron wires, left bare or juted.
There are no standard specifications for conductors of the third1 class for forest
protection telephone lines and none are contemplated by the Forestry Branch, as the
use of such lines on the reserves will be comparatively small. The cost of the heavy
cables is so great that each case must be studied separately so that the lowest-priced
cable that will give satisfactory service may be specified.
Of the cables above described, the first is the least expensive; the last, the most.
Rubber-covered wires that will give satisfactory service under unusually favourable
conditions may be secured as low as $50 per mile. Heavily- armoured cables, proof
against injury in all but the most adlverse sites, will cost from $500 per mile, up.
Intermediate types will range between these figures in cost.
In waters having any perceptible current, either the ordinary current in a
stream, OP tidal or wind currents in other bodies of water, nothing but an armoured
cable is likely to give satisfactory service. The nature of the currents, the contour
of the crossing, and the character of the 'bottom will determine the weight of armour
required.
In still waters, such as large lakes or ponds, either heavily insulated wire or
lead-sheathed wire may be used. Insulated wire without a lead! sheath should only
be used in perfectly still water where there is a mud or sand bottom in which the
wire will embed itself. Such waters will usually be shallow and have a fairly
regular profile. If used for navigation or log-driving or rafting, the chances of the
wire being disturbed by such operations must be fully considered. In nearly all
cases, where the approach to the shore is on a gradual, shelving bottom, a heavy pile
or tripod properly weighted should be set in the water at a sufficient distance from
'the shore to permit of the wire being brought to the surface in a water depth of
£ ft. to 8 ft. and carried to shore by an overhead span. The probable effect of ice on
this construction must be considered. Such spans should! not, as a rule, be over
^ mile to £ mile in length and should always be tested for some months before
permanent shore structures are erected. If they fail, replace with a lead-sheathed
cable, making the shore connection as above, and use the insulated wire for station
installations or for emergency or temporary land lines.
For spans of over \ mile in still water with a mud, sand, gravel, or rock bottom,
where excessive irregularities of profile do not occur, the most satisfactory cable will be
a lead-sheathed one. On a gravel or rock bottom it should have an outer jute covering.
The shore approach may be made as previously described, but in most cases it will be
found more satisfactory to splice on to each end of the span a short length of armoured
cable with which to make the shore approach from a depth of about 15 ft. Landings
may be made with armoured cable where the rock slopes off very steeply into deep
water; or the cable may be brought ashore on a sand or mud bottom sunk in a trench
and, if possible, protected by a light covering of rocks or gravel and a few stakes or
piles to warn off boats. However, if logs drift loose in the lake, or if the landing place
is exposed to a heavy surf, an overhead landing is preferable.
Always set up at each end of a submarine cable crossing a large sign warning
navigators against anchoring over the cable.
The actual laying of a submarine cable is very simple. The reel on which it comes
wound should be mounted on the stern of a boat of suitable size, or, if none is
7*9211-— %
82
METHODS OF COMMUNICATION FOR FOREST PROTECTION
available, on a barge or raft. This is done by inserting a steel bar or pipe in the hole in
the middle of the reel and supporting it at each end so that the reel will revolve easily
on the bar. A brake by which it may be stopped should be improvised. The end of the
cable should then be made fast to the shore and the boat run across to the other landing
at a slow speed. Two men should tend the reel and see that the cable comes off evenly.
Where any great irregularities in the profile of the bottom are known to exist special
care -should be taken to ensure that the cable lies on the bottom throughout its length
and that there are no unsupported spans.
Section 67 — Connecting Forestry Branch Lines with Private Lines or Exchanges
Whenever it is desirable to connect a Forestry Branch line with a private line or
exchange, the district inspector should first be fully advised by letter as to what ar-
rangements can be made for the connection, including a statement of the ability to
obtain night, Sunday, or holiday service, if needed in emergencies. There should also
be stated the length of the Forestry Branch line, and, in cases where it is desired to
connect directly to another line, the length of such line; the character of its construc-
f?ejL//ar /ron -f/e ,
M-ain fine
Use test clomp here
Ga/v /'ron
_ . tc/. of branch //'n e —
enough offer cfeacf encf/no~
on /nsu/crfor- X fo GOnnccrfo
//ne cr-s shown
Fig. 38 Method of connecting branch line to main line when both are galvanized-iron wire
tion and maintenance ; the sizes and kinds of wire used in the construction of both lines,
and whether one or both are grounded or metallic circuits; the number of instruments
on both lines and the ohm capacity of the instruments on the line with which connec-
tion is to be made. The district inspector will decide the best method of handling the
matter and making the connections. Every precaution should be taken to make sure
that trouble originating beyond the Forestry Branch line will not interfere with it.
Section 68 — Branch Lines
1 — METHOD OF CONNECTION
In attaching a branch to a main line, the former should be dead-ended on a separate
bracket attached to the main line pole for that purpose, so that the strain of the branch
line will not come on the connection (Fig. 38). A Fahnestock test-clamp may be used
to connect the branch line to the main line instead of wrapping the end of the branch
to the latter. The Fahnestock test-clamp is made in three grades : Entire clamp fully
FOREIGN LINES AND CONNECTIONS
83
tinned, elamp half -tinned, and un tinned. The first type should be used for connecting
two iron wires, the second for connecting a copper and an iron wire, and the third for
connecting two copper wires.
When the main line is of hard-drawn copper wire, it should be cut in two and
dead-ended on the same insulator from both directions, splicing in additional wire if
necessary. The ends after dead-ending should bereft long enough to be spliced
together in a copper sleeve, so as to complete the circuit again. The branch line
should then be dead-ended on a separate bracket and insulator, and, the connection
made as in Fig. 39.
r/o/f /engfh s/ccve
Afer/n //ne
Afa/r? //ne
r/ard drawn copper w/' re
Afa/n //ne cuf and dead ended
*v/fh haff /engfh s/eev&s -from
hofhd/ reef ions on/nsu/afor/7
<7S shown f^nds /eff/ong enoug*
offer dead end/ ng fo besp//ce
together as shown
r/ard drawn copper w/re
Soffcoppcr w/re same size asorancfi //ne
~i rubber covered 6ro/dedand
weafherproofcd copper M /re) 7 wraps
a f each end as shown
•So/dc/
•Shown ~for one w/re //nc Carounded
c/rcu/f) ~fo//ow same mefhod for
mcfa///c c/rcu/f
Fig. 39
Method of connecting branch line to main line when both are hard-drawn
copper wire
Whenever any wire is connected to a hard-drawn copper line, the latter must
always be dead-ended for that purpose, so that the wire may be soldered to a point on
the dead-end loop between the sleeve and the insulator. When soldering is not
feasible, the wire should be cleaned bright, and the wire to be connected should be
closely wrapped around the line wire not less than seven times. A Fahnestock clamp
may be used here also.
When connecting a branch line to a tree line the branch should be dead-ended on
a tree by the method prescribed in Section 60 and shown in Fig. 33. The main line
should be held by a crosstie and the connection between the branch and the main line
made with a piece of No. 14 insulated copper wire attached as shown in Fig. 40. In
order to facilitate separation of the branch from the main line, a method of installing a
switch when making such a connection is illustrated in this figure.
2 — TYPES OF INSTRUMENTS
Where a Forestry Branch line is to connect with another line, either directly or
by switches,. the resistance in ohms of the ringer coils in the instruments (and exten-
sion bells, if used) should be the same as the resistance of those on the connecting line.
The standard resistance of all ringer coils on exclusive Forestry Branch lines will be
2500 ohms. However, in connecting with lines that use other resistance ringer coils, it
will be necessary to use the same resistance coil in instruments on the Forestry Branch
line. Where telephones of other resistance than that specified are needed for use, the
district inspector should be consulted as to the proper set to purchase.
79211— 6^
84
METHODS OF VOMMUNICATTON FOR FOREST PROTECTION
/^Copper wire soldered
_, turns of
f copper tv/re so/c/ered.
^Branch
strain insulator.
fastened with
3 "* to F. H. wood screws .
No. 14- Rubber- covered, braided
and weather-proof tw'sted >v/>e.
S.PS.T.
Knife-switch ploced
6 ff. above ground.
Out of door, met hod of affachtno; branch //nes /o
rna/'n //'nes .'
Where trees suppor-t the //nes, c/eacf-eno/ as shown
6v • r/g.33 • r?un the branch /ine to the main
fine, dit-ecf/y from the hanger. The rna/n /me
shou/o/ be fastened fo a standard anchor.
Run copper wire through ho/e
in strain jnsu/ot~or for support:
Fig. 40 Method of connecting branch to main line in tree construction
CHAPTER XII
INSTALLATION OF FIXED EQUIPMENT
Section 69— Wall Sets
The standard wall telephone set will always be the most common type employed.
It is used for nearly all permanent indoor installations, except at lookouts or main
headquarters, where desk sets are desirable. The sets as received from the maker are
in a partly "knockdown" condition and must be assembled. This consists of putting in
place the receiver, transmitter, shelf, and generator crank. Suitable screws are pro-
vided, where needed, and holes bored for them. Directions for assembling accompany
each set, as shown in Fig. 41.
The location of the instrument inside the building will always be determined largely
by convenience in using it. This location should be decided upon, however, before the
line wire is brought up to the building. It is customary to stand up when using a wall
set, and the height of instrument must be determined accordingly. Instruments must
not be attached to walls with nails. Use the four If-in. No. 10, round-head, blued screws
provided, and make Certain that the screws get a sufficient hold on the wall to support
the weight of the set and the extra weight of persons leaning on the shelf. Instru-
ments installed in unlined log buildings should be attached to a suitable board and
this in turn fastened securely to the wall. Always try to place the instrument so that
it will be directly over the point of grounding.
Each standard instrument when received should have pasted to the inside of the
door, a diagram of the internal wiring and complete directions for setting up and
connecting to the line (see Fig. 41). It is to be noted that the wires from different
parts of the set are variously coloured and these colours are indicated on the simpli-
fied diagram, making it easy to identify various circuits in the set itself.
The two terminals on the right-hand side of the instrument marked Ll and L2
are the ones to which the .line wire and ground wire respectively must be connected.
[In some older types of instruments on a few reserves these terminals are -on the left
side of the box. The diagram, however, will indicate connections.]
On a metallic circuit connect one of the wires to each of these terminals. The
terminal marked GND is not used at all in the set as employed on Forestry Branch
lines.
Section 70 — Condensers
The condenser in a telephone is cut in circuit in series with the receiver. It makes
possible "through" signalling when receivers at intermediate stations are off the hooks.
Any telephone now in use, if not already provided, can be equipped with a condenser.
The condenser may also be cut in on one side of the ringers for testing purposes.
Section 71 — Dry Batteries
1 — INSTALLATION
Three dry cells are required for all instruments except the lookout sets and the
portables. Northern Electric, Blue Bell, Blue Label, or Columbia cells are recom-
mended and those with Fahnestock clips are to be preferred to those with the common
binding-post. C'onnect together as shown in Fig. 43, using insulated stranded wire
rather than solid wire, since it is more pliable. Do not remove the paper cartons
which are needed for proper insulation and take care that the adjacent zinc binding
posts do not touch.
85
86
METHODS OF OOMMUNWATION FOR FOREST PROTECTION
LINE-l
GND.
LINE-2
ORANGE;
YELLOW
GREEN BATTERIES NOT FURNISHED WITH THE SET
Fig. 41 Wiring- diagram and directions for assembling standard wall telephone set
Tools. — An ordinary screw-driver is the only tool that is required for all adjustments and
wire connections.
This set is shipped connected for service on either metallic or grounded circuits with the red
ringer lead to terminal " Line 2," the black ringer lead to terminal " Line 1," and when
there is no condenser, the yellow receiver lead to lower " cond " terminal.
When used on metallic line circuits, connect one line wire to terminal " Line 1 " and the
other line wire to terminal " Line 2."
When used on grounded circuits, connect the line wire to terminal " Line 1 " and the ground
wire to terminal " Line 2."
When used for divided ringing, that is ringing from either side of a metallic line to ground,
connect the red ringer lead in one group of sets to terminal " Line 1 " and in the other
group to terminal "Line 2." In all sets connect the black ringer lead and the ground
wire to terminal " gnd." The tip side of the central office line to terminal " Line 1 "
and the ring side to terminal " Line 2."
To connect the condenser in series with the receiver. — If not already so equipped, connect
the yellow receiver lead and one condenser lead to the upper " cond." terminal, and
connect the other condenser lead to the lower " cond." terminal.
To connect the condenser in series with the ringer (when the set is used in connection with
common battery lines). — Connect the red ringer lead and one condenser lead to the
upper " cond." terminal, the black ringer lead to terminal " Line 1 " and the yellow
receiver lead and the other condenser lead to the lower " cond." terminal
Ringer adjustment. — The armature shall be so adjusted that the clapper ball has a move-
ment of about Vir, inch. To obtain this, turn the screw " A " to the right to shorten the
stroke, or to the left to lengthen the stroke.
The gongs should be so set that the clapper ball strikes but does not rest against them
when thrown to either side. To change position of the gongs, loosen the clamping
screws " B," turn the eccentric adjusting screws " C " until the correct position is
obtained and then tighten the clamping screws " B."
In mounting the transmitter, connect the cord " A " of the transmitter to terminal " C "
inside of the door and connect the cord " B " to terminal " D " on the door.
In connecting batteries, connect wire •" E " to post " F " and connect post " G " to " H " and
"M" to "N" and connect wire "P" to post " R." See that the binding-posts " G,"
" M " and " R," do not touch each other when the batteries are in place.
Repair parts should be ordered by sample if possible, otherwise by accurate description,
always mention, if possible, the code number of this set (it is stamped on the inside of
the door n^ar the bottom edge).
INSTALLATION OF FIXED EQUIPMENT
87
Fig. 42 Standard telephone installation
(a) Front view, (&) Back view, (c) Side view
2— RENEWAL
Regular systematic renewal -of all batteries at least once a year is necessary. In
some cases more frequent renewals will be required'. For such places the 3-in-l bat-
tery, which consists of three cells inclosed in a waterproof casing with only two
exposed connecting-posts, will often be found desirable as it has a. somewhat longer
life. Batteries deteriorate rapidly whether in use or not.
Two new batteries should never be installed with one old battery, nor one new
battery with two old batteries, as one poor battery will spoil the efficiency of the good
ones.
Fig. 43 Method of connecting dry batteries for a telephone
88
METHODS OF COMMUNICATION FOR FOREST PROTECTION
3 — TESTING
For battery testing an Ever Ready, No. 1003 battery gauge is a cheap and fairly
efficient instrument, and each forest reserve headquarters should be provided with one.
Cells which test less than 10 amperes should not be accepted. 'Cells showing less than
4 amperes at the end of a one-minute test should be discarded. First-class Blue Bell,
Blue Label, or Northern Electric cells when new may be expected to show 14 amperes
on test; Columbia, 24 amperes.
4 — REMOVAL FROM UNUSED STATIONS
Always remove the battery from the telephone in stations that are to be left
unoccupied over winter, also from all outdoor sets. If left in the instrument consider-
able damage may result from leakage of chemicals. This is particularly true with the
1336-J set in which the battery is immediately adjacent to the generator.
Section 72 — Protectors
The question of protection is a very important matter and is divided into two
classes in Forestry Branch work: (a) partially exposed substations and (Z>) fully
exposed substations.
Porce/ain tube sloping
upwards from outside
through wa/lofbui/ding
as shown
fi
To //ne /er/n/nal\
of profecfor
Protector [".]
/nstde ofbui/ding
Telephone set
/*? B &S rubber covered
bra/ded and wealherproofed
*+/2Porce/a,n Knob C0flper "/re
(Use insulated wire for ty/ng)
Line
*—£nd of /me w/re /eft
fong enough after dead
ending fo be brought
back on rfse/f doi*n to
fuse <?* shown
Hang fuse /ow enough fo beeasi/y
accessib/e for reptecemenf
Shown for one wire 'fine fg rounded
cf'rcu/f) fo//ow same method for?
meta/Sic circuit;
Method of installing line fuse when required
INSTALLATION OF FIXED EQUIPMENT 89
1 — PARTIALLY EXPOSED SUBSTATIONS
Where it is absolutely certain that the line is nowhere exposed to accidental con-
tact with electric-light, power, or high-tension circuits (but only to lightning), each
telephone station should be considered as partially exposed, and nothing beyond the
No. 60-E protector used for protection. Where lightning is unusually severe, however,
either a 47-A line fuse, in addition to the 60-E protector, or a 58-F lightning protector
should be used. The former should be located immediately outside of the building
and attached to the main line wire in such a way that, when blown, the wire on the
side toward the line will fall away (Fig. 44). On a metallic line, where line fuses
are used, a fuse should be attached to each wire. When the 58-F, which is a combina-
tion of the 60-E protector with fuses, is used, a No. 48 asbestos mat should be mounted
back of all protectors and the slits in the fuses turned toward the mat.- The appear-
ance of the installation is much improved if the rough edges of all asbestos mats are
bound with brass or aluminium oilcloth binding tape, as in Fig. 84.
Special provisions are required for the protection of the lookout sets (1336-J)
and the portable telephones. These are discussed in Section 75, 80, and 81.
2 — FULLY EXPOSED SUBSTATIONS
A fully exposed substation is one on a line which may be exposed to accidental
contact with electric-light, power, or high-tension transmission lines. Even though
only a portion of a line is subject to such exposure all stations on it will be considered
as fully exposed. The 60-E protector with 47-A line fuse, or the 58-F protector, will
be used at these stations. In all cases where the line is exposed to a high-tension
voltage in excess of 1,800 volts the district inspector should be consulted in regard to
the additional protection.
3 — CONNECTIONS WITH FOREIGN LINES
In general, it is not necessary to consider the exposure along other telephone lines
with which the Forestry Branch lines may connect, provided the connection is made
through a switchboard. If made by any other means, however, one of the above-
described protective methods will be used.
4 — LOCATION OF PROTECTORS
It is dangerous to place protectors on or immediately adjacent to the telephone
sets. Always install the protector at least 2 feet away from the instrument, generally
at or very near the point of entrance to the building and as nearly over the ground
rod as possible. The 58-F protector should be mounted upon the wall so that the
fuses are vertical, and fastened in place by screws. It should not be exposed to water
or dampness or be placed outdoors. When the leading-in wires enter the building
above the door or window casing, the protector should be mounted so as to allow a
space of 1 in. between the protector and the casing. Where the wires enter at the side
of the door or casing, the protector should be mounted flush with the latter. It should
always be placed at least 12 in. from curtains, shades, or similar combustible materials
and should never be mounted directly above any such materials.
Ordinarily only one mica should be used between each pair of protector blocks,
but in localities where lightning is excessive and the stations difficult of access two
micas may be inserted, thus increasing the air gap. Paper or other material should
never be substituted permanently.
The 58-F protector should be connected as follows: Connect the leading-in wire
or wires to the fuse terminals marked L most dista-nt from the protector blocks, and
the inside line wires to the other end of the fuse terminals — that is, the end nearer
90
METHODS OF OOMMUNIOATTON FOR FOREST PROTECTION
to the protector blocks. Connect the ground wire with the terminal marked G as in
Fig. 45. In the case of a grounded line only one of the fuses is used but a short wire
GffOUNDETD C/ffCU/T
Through Through
porce/a/n poroe/a/'n
'-tube -fo Tube to
//ne ground rod
r~Or? MET/? LUC C/r?CU/T
Through Through
pOrce/ain porce/a'n
Tubes /o -fube -fo
//ne crround roc/
P.-cfector
&.5 rubber covered
braided and weafher
proofed copper wire
#/8 B &S. rubber covered
ond braided fw/sfed
pair copper wire
running from ferm/na/s
marked "//ne / * and
'//ne 2" /n -fe/ephone
se1~ -fo protector sef
as shown
Te/epnone
Fig. 45 Wiring diagram for telephone station
should be run on the end of the protector that contains the protector blocks, from the
terminal marked G to the terminal at the side of the protector blocks that is not being
used. by the main line '(Fig. 45).
Section 73— "GROUNDS"
1 — GENERAL PRINCIPLES
Telephones are grounded for two distinct purposes. In both one-wire and two-
wire (grounded and metallic) lines the protective devices must always be grounded
in order to function properly. One-wire (grounded) lines, however, require to be
grounded in order that the return half of the circuit, the earth, may be made avail-
able. In grounded lines, therefore, the character of the ground connection not only
affects the protection but also affects very seriously the operation of the telephone both
for ringing and talking. Poor grounds constitute one of the most common and most
annoying sources of trouble in this type of construction.
While permanently moist earth will generally afford a good ground, yet different
soil materials and different geological formations do not always possess the same
conducting power. This sometimes makes it necessary to test various places before
INSTALLATION OF FIXED EQUIPMENT 91
a fully satisfactory ground is secured. This is conveniently done by using standard
emergency wire to make the test connections. Dry or frozen earth and rocks are
non-conductors and will not give a satisfactory ground.
Nearly all grounding difficulties, however, arise from defective materials and
details of installation. Even after a suitable place is located, failure to satisfy the
primary requirements of good grounding, namely, a sufficiently large, clean, metallic
surface in intimate contact with permanently moist earth, will result in poor operation
of the station.
2 — -GROUNDING DEVICES
There are several first-class grounding methods. Wherever possible the stan-
dard ground rod should be used. This is a 7-ft. galvanized-iron rod, | in. in diameter.
Drive the rod in so that only a length of about 8 in. remains above the ground surface.
Place as near the instrument as practicable and close up to the side of the building,
preferably where it will receive the drip from the eaves. If it is not possible to drive
the rod vertically to its full depth it should be driven 011 a slant, for it is essential that
the moist earth come in contact with the full length of the rod. Depth of freezing
must be carefully considered1, however, and if necessary to keep below frost line the
rod may be driven at the bottom of a hole.
Wherever, for any reason, a standard ground rod is not available, a good ground
can be made on a copper plate or coil of copper wire. The plate should be about
No. 21 Birmingham sheet metal gauge or No. 21 U.S.S.M.G. in thickness and about
12 by 18 in. in size. A wire coil should be 12 in. in diameter and be composed of at
least ten turns o-f No. 12 bare copper wire. In the former case, a piece of bare copper
wire No. 12 or No. 14, must be soldered to the plate and should be sufficiently long
to reach to the surface of the ground. In the latter case, one end of the wire coil is
brought to the surface. The plate or the coil must be buried at a sufficient depth in
permanently moist earth, and the wire leading to the surface joined to the ground
wire of the instrument.
A well may be used for a grounding place, but is of doubtful value if in rock.
Use a coil of copper wire as previously described "and, place flat on the bottom of the
well, having the end at least 3 ft. above the high-water level to provide for connection
to the wire from the instrument.
When it is impracticable to find permanently moist earth, a good ground may be
obtained by placing a- similar coil of wire or a copper plate at the bottom of a hole
6 to 10 feet deep, covering it with about 1 ft. of powdered charcoal and wetting the
latter with a bucket or two of water. The hole should then be refilled and the earth
tamped in securely. Charcoal is hygroscopic, and will absorb and retain moisture.
The connection of the ground wire with the- coil must ~be soldered. A bucket of water
thrown on the ground at intervals during a dry period will add to its effectiveness.
In some buildings it is possible to use a water-pipe for a ground, in which case
the ground wire should be attached to the pipe by a Blackburn ground clamp. Only
pipes which always contain water should be used.
3 — PRECAUTIONS
Tinder no circumstances should ground wires be attached to : —
(1) Water-pipes of a town water supply if other lines are grounded on them.
(2) Pipelines not carrying water.
(3) Coils of iron wire or scraps of old iron thrown into a stream, lake or pond
having a rocky bottom.
(4) Black iron plates, horseshoes, gun-barrels, ungalvanized bars, or pipes, rain-
spouts, old 'bolts, and similar articles. Ungalvanized iron placed in contact with the
earth rusts quickly. Rust is a non-conductor and acts as an insulator. Ground trouble
is sure to follow the use of the above articles.
92 METHODS OF COMMUNICATION FOR FOREST PROTECTION
4 — MULTIPLE GROUNDS
The following instructions taken from the Telephone circular of District No. 5,
United States Forest Service, apply to stations where several lines converge: —
" Where more than one line enters a station to telephones, extension bells, or a
switchboard, all the instruments having the same ringer resistance may sometimes
be grounded on the same ground rod or coil, provided the electrical contact to the earth
is satisfactory.
" The efficiency of a common ground should first be tested before making perma-
nent connections to it. Where the rod or coil is immediately adjacent to the instru-
ments simply connect it to the instrument by a temporary wire. All points of connec-
tion should be clean and tight. If a satisfactory ground cannot be found nearby, the
test may be made by stringing No. 9 wires to different places which appear to be satis-
factory until good grounds are found. (Test by attaching one instrument to the wire,
the wire leading to the experimental grounding-place, and if satisfactory results are
obtained connect in turn lead wires from each additional instrument.) Cross-talk
between the lines may be heard even if the ground is good, but it should not be pro-
nounced. When a signal is rung over one of the lines the bells should not cross-ring ;
that is, two bells or more should not ring with the switches open between the respective
lines. If the cross-talk is loud and the bells cross-ring, or if cross-talk is loud in the
absence of cross-ringing, inadequate ground to carry the full number of instruments
attached is indicated. Two or more wires leading to grounds should not closely parallel
one another.
" Further experiments should be made by disconnecting one instrument at a time
from the lead wire, followed by a test until the cross-ringing is eliminated and the
cross-talk either eliminated or much weakened. Only in exceptional cases, if ever,
can cross-talk be entirely eliminated where several grounded lines enter the same sta-
tion. Seek additional ground or grounds for lines that were disconnected.
'"It may be necessary in some cases, in order to get satisfactory service, that
grounds be separated as much as half a mile. The expense, however, of locating effi-
cient grounds and of installing connecting facilities is justified, because instrument
installation is a failure unless good grounds are made."
Section 74 — Wiring
To ensure good service, instruments on both grounded and metallic lines must be
installed in the proper manner. Figs. 42, 44, 45, and 46 illustrate graphically the
method of making the entire installation.
Before beginning work, means should be taken to determine the arrangement that
will be the simplest, the most economical, and the easiest to maintain.
1- — OUTSIDE OF BUILDING
(a) Leading -in wires. — If possible, the telephone should be located on the same side
of the building as the pole from which the branch line originates. The wire from
the line should be dead-ended on a bracket and insulator attached to the outside of
the building. A line should never be attached to a building directly from a tree, and
not more than 50 ft. of No. 9 iron wire should intervene between the building and
the nearest pole. Set an extra pole or use insulated copper wire. Try to have the
pull on the bracket attached to the side of the building parallel to the wall, and not
at right angles, and always rake the bracket slightly against the pull.
The point where the wire enters the building should be as near as practicable to
a permanent ground, and each ground wire should pass through the wall of the building
in a separate porcelain tube, spaced at least 2J ins. from the other tubes, and sloping
upward from the outside. Under some conditions circular loom may be a satisfactory
substitute for the porcelain tube, though it should not be used without permission from
INSTALLATION OF* FIXED EQUIPMENT
93
the -district inspector. Each wire as it enters the porcelain tube outside the building
should have a small drip loop about 2 in. long to prevent water from following it into
the building. The location of the protector in the building should be determined before
the holes are made. It is often possible to locate the holes immediately above or below
the fuse terminals on the protector, thus securing the shortest length for the leading-in
wires.
Fig. 46 Method of making entry to building from main line
The leading-in wires should not enter at the attic roof unless other ways are im-
practicable. In every case the holes should be started from the inside of the building.
The line terminals of the protector should be connected to the line wire by single
No. 14 B. & S. gauge, braided and weather-proofed, rubber-covered, copper wire. The
leading-in wire should be soldered to the loop just below the insulator where the line
wire is terminated (Fig. 44), and should not come in contact with any part of the
building.
Cb) Ground wires. — Single No. 14 B. & S. gauge, rubber-covered, braided and
weather-proofed, copper wire should be used to connect the protectors with the ground
rod or ground wire.
Ground wire outside of the building should be (Supported on No. 4£ or No. 5£ porce-
lain knobs. The knob should always be attached with a flat-head screw, and not with
a nail.
The wire from the protector to the ground should be laid as directly as possible,
and should have no spirals, coils, knobs, or sharp bends. The ground wire should never
be placed near sheet-iron roofing, drain-pipes, etc., on the house.
2 — INSIDE OF BUILDING
All joints and1 splices of the wiring inside or outside of the building should be
soldered and taped. This does not apply to the connections made at the terminals
provided in the apparatus. Where a twisted pair is spliced, the joints should be
soldered at least 3 in. apart. In soldering, resin should be used as a flux. Chloride
of zinc; sal ammoniac, or other fluid fluxes are not satisfactory. The wires to be
soldered should first be scraped thoroughly and cleaned.
All knob-and-cleat work should be done as neatly as possible. Wiring inside and'
outside of a building should be run in as nearly vertical and horizontal lines as
94 METHODS OF OOMMVNWATTON FOR FOREST PROTECTION
possible. This gives an appearance of neatness and simplifies tracing out the wires
when hunting for trouble. There should be no knots or spirals in the wiring (this
does not mean joints and splices) between the protector and the line or ground rod.
The line should 'be kept at least 1 ft. away from the overhanging eaves if the roof
is of sheet-iron. 'Wet and! damp localities should be avoided for inside wires.
The telephone should be connected to the protector by means of No. 19 B. & S.
rubber-covered and braided, single or twisted-pair copper wire. However, if this
wire is not available, the heavier insulated outside wire may be used, although it
is not so cheap. The wire inside the building should be' fastened to the wall with
insulated tacks, milonite nails, or approved cleats. Uninsulated' tacks or staples
should not be used. No joint in insulated wire should touch an adjacent joint in
another insulated wire, even though both are taped.
(a) Protection from pipes. — Wherever practicable, wires should be placed above
all pipes or other conducting material. When a crossing is necessary the wire
should be protected by two wrappings of insulated tape, the latter extending at
least 1 in. each side of the pipe or conducting material.
(fr) Separation from light and power lines. — When it is necessary to cross an
electric-light or power wire in the building there must be a separation of at least
6 in., unless tne telephone wires are incased in a circular loom or porcelain conduit.
When so incased the conduit should project at least 6 in. on each side of the electric-
light or power wire and be firmly secured against slipping.
Section 75— Lookout-station Telephone Sets
The 133'6-J telephone, special forest protection type, contains a 2600-ohm unbiased
ringer and condenser. The 1336-K telephone contains a 1600-ohm unbiased ringer
and cond'enser.
An iron-box telephone set outdoors should be mounted on a post in preference
to a tree or topped tree. The iron case of the box should be grounded by wrapping
a wire under the head of one of the mounting bolts when the latter is screwed in
and then running it to the ground rod (Fig. 49.) A switch and protector mounting-
box should be atfached' to the post. The line wire should be properly dead-ended on
a bracket and insulator located on top of the post and extended to the switch by
means of No. 14 B. & S. gauge, rubber-covered, braided and weather-proofed, copper
wire. This wire should then extend from the opposite side of the switch to the
line terminal of the protector and from there to the proper terminal in the telephone
set, through the hole in the latter provided for the purpose. The same kind of wire
should extend from the ground Tod to the ground terminal of the protector and to
the proper terminal in the iron-box telephone, through the hole provided in the
latter.
If this set is employed on a metallic circuit, a double-pole, single-throw switch
should be used (Fig. 49). From each of the line wires an insulated copper wire
should extend to a switch, and' from the opposite terminal to its proper terminal
on the protector, and thence into the iron-box set. The latter is grounded from
the mounting bolt, while another 'wire runs from the ground terminal of the protector
to the ground rod.
Installations of this character may be placed on lookout points where there is
nothing but rock. The post may be bolted to the rocks and the ground rod located
wherever .a suitable place can be found, even though it is a considerable distance
away. In this case the wire to the ground rod is run in the same manner as line
wire is run. Metal brackets and fixtures may be used to support the line wire along
the side of the rock, with extension bolts if required.
INSTALLATION OF FIXED EQUIPMENT
95
96
METHO'DS OF COMMUNICATION FOR FOREST PROTECTION
Pig-. 48 Lookout station telephone set installed in the field
Section 76 — Howler and Condenser for Vibratory Signalling
The signals from the 1004- A portable telephone set are received at the stations
by means of a howler (Fig. 82). Every station which it is desired to call directly
with a portable set of this type must be equipped with a howler, but in most cases
it will be found satisfactory to equip thus only the more important stations and
call others by first signalling those with howlers and having them raise the desired
station in the usual way by bell signals. The howler must be bridged between line
and ground through a 1-microfarad condenser, except on very short lines with light
loads when it may be bridged between line and ground direct. The most convenient
method of wiring the howler connection is to bridge between the line and ground
posts of the protector in the case of a grounded line (Fig. 5'Q) and between the two
line posts of a metallic line.
The two binding-post? on the howler will generally be found marked L and G.
In making the installation run an insulated wire from the line side of the protector
to one post of the condenser. From the other condenser terminal run a wire to the
L post of the howler and then connect the G post of the latter to the ground or
G terminal on the protector as shown in Fig 50. Do not reverse these connections
on the howler as this will reduce the signalling capacity.
Howlers should all be adjusted after being permanently installed. They should
never be touched, except for the purpose of adjustment, after they are once located
and adjusted.
INSTALLATION OF FIXED EQUIPMENT
97
W/rin
?y D/aqrom -forGrounc/etf C/rcu/f W/r/nj D/ogrom -for/Me-fa///c G feu if
To /tne
Th/s mounting bo
/7?<7y be /ocated atony
po
Mounted in -switch one/
mount/ na box
fo be # /4 B &. S
rubber covered bra/ded and
p-roofed coppem/rc
/f~7~h/s wire runs on A/ -from
underneath ~fne head of mounfc
-/ng /oa -screw fo O round rod
o-s-sr/owr> and grounds fhe/ron
box -Scrape enornG'/ off fo in-
sure cjood confacf~af/aq s
when a 'riven /n ~f~/gftf~
/fc/esired ' fh/s
af ground ferm/ no/ of protector
instead ofatorvvnd rod as shown
Ground ffocf
Fig. 49 Method of connecting lookout station telephone to line and ground
79211—7
98
METHO'D® OF COMMUNICATION FOR FOREST PROTECTION
To line
Howler
Condenser^
To be atfoched to wo /I
pieces of leather and screws
Lightning
Protector
Ground
Fig. 50 Method of connecting howler and condenser
Section 77 — Coils
1 — LAVITE COILS
These coils are used to remove static electricity from the line. Each coil should
have a resistance of 48,000 ohms, and be inclosed in a small weather-proof box. (See
Section 93, Static Electricity) . It will generally be necessary to install these coils
outdoors on poles along the line. The method of installation is illustrated by Fig. 51.
2 — KEPEATING COILS
The standard 47-A repeating coil is generally placed indoors as part of one of
the special installations described in Sectjon 78. In such cases no special precautions
with regard to the placing or wiring of the coil are required, except to see that it
is guarded by the protective devices in the same manner as the other apparatus and
that the eight connections are properly soldered.
In some cases the necessity arises for placing one of these coils outdoors. When
this is required the coil should be placed near the top of a pole and the latter may
be provided with pole-steps if desired. Coils should not be installed on trees. Two
protectors will usually have to be placed between the coils and the lines, and the,
whole inclosed in a waterproof box. The method of making such installations is
fully illustrated in Fig. 52.
INSTALLATION OF FIXED EQUIPMENT
99
Fig. 51 ^Method of installing Invite -coil to drain line of static electricity
Section 78 — Special Installations
It is possible under this head to discuss and illustrate only a few of the more
common types of special connections encountered on forest protection lines. <In
many cases the local conditions at the station where the installation is made must
determine the details of the connections. A knowledge of general principles such
as are stated in Chapter XIV, together with a study of the reference works listed
in Appendix B will often enable the officer in charge to work out the best type of
connection. However, problems sometimes arise, especially where foreign lines are
involved, that are highly technical in character. These should be referred to the
district inspector with a full statement of all the material facts in each case.
In the following description of special installations reliance is placed largely
on diagrams. Fig. 53 is the legend which shows how the various parts of the tele-
phone equipment are graphically represented in these diagrams-
79211— 7
100
METHODS OF COMMUNICATION FOR FOREST PROTECTION
INSTALLATION OF FIXED EQUIPMEyV 101
1 — EXTENSION BELLS
Two types are listed as standard equipment by the Forestry Branch. These
bells are simply an ordinary polarized ringer inclosed in a suitable box for mounting
at any point where it is desirable to receive telephone calls but not necessary to
install an instrument. The uses of extension bells are as follows:—
m v y
'<? 5"vy/e jr Dovbtepo/a 3~/'sjcj/e \ 11 >
'//£/* 0 fhro* 3W/C/? U
n n
n
Fig. 53 Legend
(1) To enable calls to be received separately from the several lines which ter-
minate on a switchboard.
(2) To enable calls to be received in remote parts of a building or in other
buildings at a distance from the telephone instrument.
(3) To enable calls to be received outdoors at a distance from the telephone
instrument.
Each bell is provided with two terminals and is connected to the line in the
same manner as a telephone instrument, that is, on a bridging line it is bridged
between line and ground or between the two wires of a metallic circuit. Extension
bells must always be protected from lightning and other high-tension currents, as are
telephones.
Extension bells with gongs of different shapes and tones may be secured and
are used to make it possible to distinguish signals on different lines from each other.
Where different tone bells cannot be secured^ the tone may be altered by placing a
wire across the gongs or by sawing a small notch in one or both gongs with a hack-
saw.
2 — MULTIPLE LINE SWITCHBOARDS
It is frequently necessary to install switching stations on long lines in order to
keep circuits down to workable lengths. These will usually be placed where a branch
makes possible the separation of three lines. The switching method shown in Fig. 54
should be used where the three lines are not connected most of the time. It requires
the following equipment : Two extension bells, one telephone set, and three single-
pole, single-throw, baby knife-switches. With the three lines connected, two exten-
sion bells and the telephone remain across the line.
The method shown in Fig. 55 should be used where the three lines are connected
most of the time. It requires the following equipment; Three extension bells, one
102
QPF ,31' COMMUNICATION FOR FOREST PROTECTION
f
~],
L— J
,3
-fJ
0O
{., i-t.
00
£*:/e/?5/OS> 6<2//
Fig. 54 Switching station, first met-hod
oo
Fig. 55 Switching stat.ori, second method
INSTALLATION OF FIXED EQUIPMENT
103
telephone set, and three single-pole, double-throw, ba'by knife-switches. With all the
three lines connected just the telephone remains across the line, the three extension
bells being disconnected.
When it is desired to receive buzzer signals at a switching station, each line must
be separately .equipped with howler and condenser. Since it is impracticable to vary
the tones of buzzers sufficiently to enable them to be distinguished readily one from
another, it may be necessary to locate the various howlers in different parts of the
room or building in order to be able to tell which line is calling.
Mote
Fig.
co//, remove
Wiring and connections on 47-A repeating coil
oc/or new co//s.
3 — STANDARD REPEATING COIL
The 47-A repeating coil is the most reliable and serviceable coil, both from a
talking and signalling standpoint, and should be used wherever possible. This coil
is also used for phantom work. By " phantom " i,s meant the utilizing of both sides
of a metallic line as one wire. As illustrated in Figs. 57 and 87, an additional tele-
phone circuit is thereby obtained. The repeating coil is also used whenever it
becomes necessary to jom a grounded to a metallic line. An 8-A repeating coil is
cheaper than the above and may sometimes be used for the latter purpose.
The details of construction, and the arrangement and designation of terminals
of the 47-A coil, are shown diagrammatically in Fig. 56.
4 — PHANTOM CIRCUIT
It is possible under certaiji conditions to carry on two or more conversations
simultaneously over the same telephone wire without interference. This is done by
installing a phantom circuit, the most common type used in forest lines being ;=•
grounded phantom out of a metallic rural line.
The following equipment is necessary: Two 47-A repeating coils, one extension
bell, and one double-pole, double-throw, baby knife-switch. By the method shown in
Fig. 57, the Forestry Branch utilizes both wires for their line, the connection with th«
104
METHODS OF COMMUNICATION FOR FOREST PROTECTION
Branch line being made at the end of the rural line circuit, thus eliminating the
necessity of stringing an additional wire parallel to the rural line telephone circuit.
By the use of the phantom circuit a direct line is obtained to the exchange or town
where the rural line terminates without interfering with subscribers on the latter. The
circuit is so arranged that the grounded Forestry Branch line may be cut on the
metallic line direct through the 47-A repeating coil in an emergency. It is also
To
Co//
Fig. 57 Phantom circuit
arranged so that, should any of the ranchers desire to talk to one of the stations on the
Forestry Branch grounded line beyond the point where the rural line terminates, by
calling the station at the end of this line the switch at that point may be thrown and
direct connection had. This phantom circuit can only be built up where the metallic
line does not parallel any electric-light, power, high-tension, or railway wires.
5 — CONNECTION OF GROUNDED TO METALLIC CIRCUIT
The necessity for making this type of connection frequently arises where the
Forestry Branch lines are joined to private or provincial lines near forest reserve
boundaries or at ranger stations, in order to give through service from points in the
reserve to points outside. It sometimes arises, also, when Forestry Branch metallic
circuits are constructed in order to eliminate inductive disturbances from power lines
or other circuits in their vicinity.
A method of installing a switching station where a grounded Irne may be cut
through to a metallic line with a 47-A repeating coil in circuit is shown in Fig. 59.
Equipment necessary: One 47-A repeating coil, two double-pole, double-throw,
baby knife-switches, and one telephone set. This method is used where connection is
necessary with some commercial toll line, one telephone being used on the commercial
line and the other on the Forestry Branch line. If a subscriber of the commercial
telephone company, or provincial line, is using the toll station, the call on the Forestry
INSTALLATION OF FIXED EQUIPMENT
105
Branch line may be answered at the same time, thus avoiding delay or interruption.
When it is necessary to connect the grounded line to the metallic line, both switches
should be closed, only one telephone being left across the line.
Fig. 58 Connecting grounded line to metallic line through a repeating coil
without switches. Dotted lines indicate connections when an
8-A coil is used
Fig. i59 Connecting grounded line to metallic line by use of switches and two
telephones
A method of connecting a grounded line to a metallic line so that either can be
used with the same telephone is shown in Fig. 60.
106
METHODS OF COMMUNICATION FOR FOREST PROTECTION
Equipment necessary: One 47-A repeating coil, two double-pole, double-throw,
baby knife-switches, one double-pole, single-throw, baby knife-switch, one extension
bell, and one telephone set. This circuit is arranged with one, telephone and signal
bell, so that a person at the station may talk on either line by using the same telephone.
The operation of the switches is as follows: Switch 1 closed down, switch 2 open,
switch 3 closed — telephone on metallic line direct. Switch 3 open, switch 1 closed
down, switch 2 closed down — telephone on grounded line direct. Switch 3 closed,
Fig. 60
Connecting grounded to metallic line by use of switches and one
telephone
switch 1 closed up, switch 2 closed up — grounded line cut on to metallic line through
repeating coil direct, instrument remaining across entire line. This circuit is so
arranged that the instrument may be left on the grounded line and the extension bell
will ring if a person at this station on metallic line is called. Switches 1 and 2 should
never be closed down at the same time without opening switch 3, as by so doing the'
metallic line would be made very noisy.
6 — SUPERIMPOSING TELEPHONE ON TELEGRAPH CIRCUIT
It is readily possible to use a telegraph line either grounded or metallic for simul-
taneous telephone service without interference, providing automatic sending-instru-
ments are not being used on the telegraph circuit or on adjacent ones on the same
poles. At least two distinct methods of superimposing are employed, each of which
has several modifications affording a considerable number of different systems adapted
to various conditions. It will usually be found that the object sought is to employ
an existing telegraph line for forest protection telephone service, but since the exact
system that must be used will depend in each case on the arrangement and character-
istics of the telegraph circuit it will be necessary that each case be referred separately
to the district inspector for instructions. When reporting to the inspector state the
number of telegraph wires available, whether they are operated as grounded or metallic
INSTALLATION OF TEMPORARY EQUIPMENT
107
circuits, the number and position of all telegraph stations on the line it is proposed
to- use, the size and kind of wire and whether the telegraph operates by single or double
current, simplex, duplex, quadruplex, or automatic.
Telegraph Instrument
_cT^
Battery -=-
Jeleyraph Instrument
f ^U-
00
00
Fig. 61 Method of using one wire for simultaneous telegraphy and telephony
Bell signals cannot be employed on superimposed circuits so that most of the
standard Forestry Branch telephone instruments cannot be used on such lines without
modification. The 1004- A set which employs buzzer signals may be used, however.
In the majority of cases the object will probably be to superimpose a grounded
telephone circuit on a grounded single-current telegraph circuit. The telegraph
employs direct current while the telephone employs alternating current. If, therefore,
condensers are inserted between the telephone rnstruments and the line, there will be no
tendency for the telegraph current to escape to ground through them, while on the
other hand the alternating currents of the telephone are not of sufficient strength to
affect the telegraph instruments. The simplest form of such a superimposition is
shown diagrammatically in Fig. 61.
CHAPTER XIII
INSTALLATION OF TEMPORARY EQUIPMENT
Section 79— Types of Portable Sets
Portable telephones are used for two principal purposes. To a certain extent
they are required for testing lines, both during construction and in maintenance opera-
tions. Portable sets used for these purposes are usually known as " test sets." These
are on the market in great variety, each type being adapted by the details of its con-
struction to some particular class of work. Some of these sets are very low-priced and
light in weight, but none of them meets successfully the special problems ordinarily
encountered on forest protection lines.
In. addition to their use for testing lines, portables are required in forest protection
for establishing temporary emergency stations on or adjacent to the permanent lines of
communication. The average conditions met with on forest telephone lines demand a
portable set of considerable power, especially in the generator. This instrument must
approximate the capabilities of the very powerful standard sets employed in the per-
manent stations and must be adapted for use on lines with them. Furthermore, since
108 METHO'DS OF OOMMUNICATIOX FOR FOREST PROTECTION
it must be carried frequently on pack-horses and saddle-horses and be subjected to
rough field usage it is essential that it be self-contained and well protected against
external injury. Finally, light weight is important. To meet these requirements it
was necessary to design an entirely new -style of portable set. The 1375- A set of the
Northern Electric Company was the result, and it has been adopted as standard by
the Forestry Branch. No other type of test set may be purchased except with the
approval of the district inspector.
The weight of the 1375-A set, however, was still found to be a handicap to its
use -by moving patrol, especially foot patrolmen, and a still lighter instrument was
designed. This is the 1004-A set of the Northern Electric 'Company which weighs oTily
2* pounds with battery and may be carried in the pocket. It uses the military method
of vibratory signals and has been standardized for use by the Forestry Branch.
Finally, occasions sometimes arise when it becomes desirable to provide more
com'plete telephone service at temporary stations than either of the above sets is
capable of affording, but where extra light weight is not essential. As a rule this is
accomplished by using a wall set, but obviously these are poorly adapted to rough
methods of transportation. To meet this requirement a combination of certain
standard equipment into a single set known as the Forestry Branch emergency set
No. 1-A has been devised. These sets are not .available for purchase but may be
assembled locally or secured from the district inspector.
Section 80— Forestry Branch Portable Telephone
1 — USE IN FOREST PROTECTION
The special portable telephone (Northern Electric 1376-A, Fig. 6<2) being adapted
for use on any line employing code signalling by polarized bells lias a wide application
in forest protection wherever its weight of 9 pounds is not a serious bar. It is more
widely applicable than the Adams hand set herein described, although considerably
more expensive, also. The particular .advantages that this set possesses are as
follows : — * .
(1) It is entirely self-contained in a stout leather case and capable of with-
standing very rough usage.
(2) It will call by bell signals any permanent station or any temporary station
provided with bells. It will also call any station equipped only with a howler.
(3) It is provided with a protector and, therefore, may be left connected to the
line without fear of injury from lightning.
(4) It is provided with a buzzer and, therefore within limits, may receive a
signal from a distant station.
(5) Although normally it uses only a small flash-light battery, it may, if desirable,
be equipped with ordinary dry cells.
These advantages are offset only by the weight and cost of the set, and' where
the former is not very objectionable the set should be used.
In general, portable sets are a useful feature of the equipment of rather highly
specialized forces only. They presuppose the existence of a fairly well developed
system of lines of 'communication and of time standards, which make it imperative
that these lines be available for use by the field staff regardless of the location of per-
manent stations. No telephone system can be provided' with permanent stations so
numerous that considerable time will not be required to reach them from the average
point along the line. Both cost and electrical load requirements restrict the number
of possible stations very materially. Wherever, therefore, the average time required
to reach a permanent station in order to send an emergency message is greater than
the protection standards will permit, portable sets must be made a feature of the
-equipment.
INSTALLATION OF TEMPORARY EQUIPMENT
109
This set will be found particularly useful for railway-speeder patrol. It should
be mounted on the speed'er in a suitable box and may be connected by a switch to the
ignition battery. By the exercise of a little ingenuity a speeder may be -equipped for
almost instant communication from any point 'along the line, and lire may be at once
reported without -the necessity of running to the nearest station.
The set is also well adapted to all sorts of repair and construction work and
where travel is largely by team, as in many of the reserves of the Prairie Provinces,
Fig. 62 Forestry Branch portable telephone set (1375-A) with ground rod
and connector
it will be found superior to any other for general use 'by forest officers. It is not,
however, well adapted to either foot, horse, or canoe patrol, but may be employed on
motor boats.
2 — CHARACTERISTICS OF 1375-A SET
The weight of the set is 9 pounds and the outsidte dimensions 3£ in. by 6J in. by
9 in. It is contained in a sole-leather case and provided with an adjustable shoulder-
strap. The interior contains an aluminium angle-plate to which is attached all the
equipment except the receiver, transmitter, and switch. These are combined in a very
light, compact, aluminium hand set. The angle-plate is itself fastened to the leather
110
METHODS OF COMMUNICATION FOR FOREST PROTECTION
case by screws. A wooden block on top bears the two binding-post connections and' a
spring clip in which the detachable generator erank is carried. Inside the lid of the
leather case is a diagram of the connection (Fig. 63). The hand set is carried i
small compartment alongside the rest of the essential apparatus and is connected per-
manently to the set by a stout receiver cord. A small, black button at the receiver
end must be pressed while using the set for talking or listening. This takes the place
Fig. 63 Wiring diagram of Forestry Branch portable telephone
of the switch-hook in the ordinary telephone. The 'battery employed is a three-cell,
Hat, flash-light type, such as the 703 Ever Ready. This battery is inserted by remov-
ing the two top screws on the side bearing the generator crank and .shoving the bat-
tery in with the contact plates foremost. When it is desirable to use the ordinary
type of dry cell with the set, one or two may be connected by insulated wires attached
under the heads of the screws that fasten the battery contact springs located in the
back of the battery, chamber. As the button on the hand set closes the battery circuit
it is particularly necessary to be sure that it is not depressed by the receiver cord
or case when the set is packed, as otherwise the battery will rapidly exhaust itself.
The hand set is of very light aluminium and must be carefully protected against
injury. Dents near the switch may make contacts that reduce or destroy the efficiency
of the instrument.
Section 81 — Adams Hand Set
1 — USE IN FOREST PROTECTION
The necessities of the more highly specialized forest protection forces demand a
type of instrument that may be available to every member of the field staff, regardless
of the transport facilities employed. Experience has demonstrated that oiily an instru-
ment that may reasonably be described as a pocket type will meet these requirements.
When it is remembered that some of the more perfectly organized forces require hourly
INSTALLATION OF TEMPORARY EQUIPMENT
111
reports from the field force throughout the danger season, this need will be readily
appreciated. It has been successfully met by the invention of the Adams hand set
(Northern Electric 1004- A, Figs. 64 and 66).
Fig. 64 Adams hand set (1004-A) with carrying case and connector and grounding knife
NOTE;- CONTACT AT A SHALL
NOT BE MAOIWHEN'TALK
BUTTO* 'S PRESSED.
Fig. 65. Wiring diagram of the Adams hand set (1004-A)
This hand set is so small aTid light that it is as conveniently carried as a fair-
sized field-glass. In addition it is considerably less costly than the Forestry Branch
112 METHODS OF COMMUNICATION FOR FOREST PROTECTION
portable telephone and compares favourably in this respect with the low-priced test
sets. Its advantages, however, are almost wholly those of weight and price, but both
are so considerably in its favour that it has a very wide application in specialized forest
protection.
The disadvantages 'of this set are as follows: —
(1) It cannot be used to call a statio-n equipped with the standard instruments,
unless an auxiliary signalling device is installed.
(;2) It has no protective equipment and cannot safely be left connected to a line
when not in use.
(3) No means are provided by which a station equipped only with this set can
receive a call. Auxiliary apparatus must be available.
2? — CHARACTERISTICS OF THE 1004^ A SET
The weight of the set is 2'£ pounds and the length over -all is 9-| in. This set
eliminates entirely the heavy, alternating-current generator needed for ringing the
ordinary type of polarized bell by substituting an entirely different system of signalling,
and thereby greatly reduces the necessary weight. Transmitter and receiver are the
same as with the portable telephone and a larger, three-cell, cylindrical, flash-light
battery is employed. A switch with two push-buttons is provided. One of these is
pressed for signalling, the other while talking and listening. The novel feature of this
set is the induction coil, which, besides serving the usual purpose in speech transmis-
sion, also serves to produce a very rapidly alternating current, used in signalling in
place of the generator and bells. This is accomplished 'by equipping the coil with a
vibrator which makes and breaks a contact in the primary of the induction coil.
The whole apparatus is inclosed in a special aluminium case and equipped with
two binding-posts at one end for connection to the line and ground. The proper
connections are designated L and G, respectively, on the sides of the instrument near
the binding-posts, and it is important that the line and ground wires be attached to
the right posts, as otherwise the efficiency of signalling is reduced.
Calls are made by a system* of long and short buzzes. These are produced by
depressing the button marked " 'Signal." After signalling, the " Talk " button is
depressed to use the instrument for conversation. Long conversations with the portable
must be avoided as the longer the conversation, the greater the drain on the battery.
The batteries should last with ordinary usage six or eight weeks and care should be
taken to see that fresh ones are secured for renewals. The Ever Ready Tungsten No.
705 is the type employed. When inserting a new battery in the battery chamber it is
necessary to put the top of the battery in first, so that the spring of the battery chamber
cap has the broad surface of the bottom to bear on.
The signals from this set are received by a howler. The installation of this
apparatus has been described in Section 7'6. The instrument itself is described in
Section 86. The presence of a number of howlers on the line is objectionable for not
only do they produce a disagreeable noise when a signal is sent in either by generator
or vibrator, but all conversation on the line is audible in any room where a howler is
placed. Howlers should be installed only at the principal switching centres or at such
stations ,as are most continuously occupied. Ordinarily they should be at least 30
miles apart and may be at greater distances. Any station not equipped with a howler
may be called with the usual bell signals through one of these switching centres.
In using the Adams hand set it is necessary to keep in mind that it is entirely
unprovided with a protector and, also, that when it is connected to the line it acts as
a direct ground. It should, therefore, not be left connected to any line when not in
use, as it would not only be exposed to serious injury from lightning but would prevent
other stations from ringing past it. It should also be noted that the sound of the
vibrator when received in an ordinary receiver over lines of ordinary length is not
INSTALLATION OF TEMPORARY EQUIPMENT 113
only painful but might be dangerous to the ear. 'Special precautions must always be
taken to make sure that the line is not in use before attempting to call a station with
this hand set.
The aluminium case is thin, and dents or other injuries which it might receive
from rough handling can easily form contacts that may destroy the usefulness of the
set. These must be carefully avoided and the sets must always be transported in the
leather cases furnished with them. These cases are made large enough to hold the
necessary connectors and a folding ground rod.
m
Fig1. 66 Forest officer preparing to use the Adams hand set with
Cree knife for ground rod
3 — BUZZER SIGNALLING
The vibratory currents produced by the Adams hand set are of very high-tension
and will traverse lines that are in such poor condition that bell signals will not pass
over them. It is therefore feasible, when lines for any reason are in extremely poor
condition, to call stations with this set at much greater distances than with the bells.
It is even possible to signal across breaks in the wire providing the ends of the broken
wire make a good ground contact, preferably with moist earth. In this case, however,
signals cannot be heard in the howler but can only be heard in a receiver held to the
ear, which restricts the practical utility of this capacity to those few forests that
maintain permanent telephone operators with head receivers. Tests have shown that
signals are plainly transmitted across a 65-ft. gap and may be distinguished very
faintly across a 210-ft. gap. They will also traverse miles of bare iron wire lying
on the ground, even in wet weather, and at a distance of one mile may be heard in the
howler. The sound produced in an ordinary receiver at a distance of 50 miles over
very poor lines can be heard several rods away. At a distance of 200 miles over lines
too poor for transmission of speech, signals are plainly audible in the receiver when
held to the ear. and weakly audible in the howler.
79211—8
114 METHODS OF COMMUNICATION FOR FORE 1ST PROTECTION
This capacity for very long distance transmission over poorly insulated or even
broken lines makes it feasible to consider the set as a possible auxiliary communication
device for sending telegraph messages, even when the lines will not carry telephone
messages. This buzzer telegraphy is the most common method employed for military
communication over field cable and other insulated- wire lines laid on the ground.
The International Morse code is used and dots and dashes are represented by short
and long buzzes. The Adams hand set would require some modification if used in
this way to' any considerable extent, but there are possibilities for utilizing it in
emergencies wherever the protection forces have the requisite training and organization.
It is also to be noted that the buzzer signals of this set may foe transmitted
simultaneously with ordinary Morse signals over one wire (see 'Section 78).
Section 82 — Emergency Communication Kits
1— USE IN FOREST PROTECTION
It frequently happens that temporary telephone stations must be established in
the field, as at fire-camps and other camps where messages must be received as well
as sent. The Adams hand set alone cannot receive a call, while the sound of the
Fig-. 67 Forestry Branch emergency communication kit No. 1-A
buzzer in the Forestry Branch portable telephone is inaudible at a few yards.
Either a howler or an extension bell must be provided where signals are to be received.
Communication kits comprising the necessary instruments for two stations with
emergency wire and tools for stringing it, all packed into suitable cases for pack or
wagon transport, are employed by certain protective organizations. A somewhat
similar kit comprising the instruments above mentioned has been devised for Forestry
Branch use. It is only necessary to add a case of emergency wire and a reel to this kit
to have a full emergency outfit.
INSTALLATION OF TEMPORARY EQUIPMENT
115
2 — CHARACTERISTICS OF THE 1-A SET
The purpose of this set is to afford a field instrument that is self-contained, will
stand rough usage, receive both buzzer and bell signals, and be available for use with
either of the two standard portable telephones. In addition, space is secured for the
grounding and connecting devices, extra battery, and some small installation tools.
The 1-A set is a shallow wooden box divided into two compartments of unequal
size. In the smaller compartment is mounted the following standard equipment: 1
extension bell, 1 protector, 1 howler, 1 condenser.
The larger compartment is fitted with two binding-posts, from which wires lead
to the external connections on the set as shown in Fig. 68.
rL /ne
Prole do
Connect a /Z75-A or IOO4--A
portable telephone of binding
posts A and B
Ground)
time
g>
Fig. GS Wiring diagram of the No. 1-A kit
It is arranged so that either the 10'04-A or the 1375-A portable telephone may be
placed in it, connection being made to the above-mentioned binding-posts. Plenty of
space is left in this compartment for tools, connectors, etc., and a' suitable holder
provided for the ground rod. On the top and ends strong leather handles are attached
by which it may be lashed to a tree or other support as shown in Fig. 69.
This set weighs 26 pounds complete with all equipment, including the 1375-A
telephone. With the 1G04-A set it weighs 19^ pounds. It may be placed on a table or
other suitable support if used indoors. The doors open downward and serve as a
writing shelf.
Section 83 — Temporary Connections to Permanent Lines
The method of connecting emergency wire to permanent lines has been described
in Section 62. It frequently becomes necessary to make rapid connection with over-
head wires from the ground. Such connection must be made, for instance, when cutting
in on the line with any of the portable telephones previously described, and it is
essential that both connection and disconnection be made quickly without the necessity
for climbing poles or trees. To accomplish this some special apparatus has been devised.
1 — EMERGENCY CONNECTORS
• The type adopted by 'the Forestry Branch consists of two pieces of No. 18 stranded,
insulated wire, one of which is 25 ft. long and the other 8 ft. The former is provided
79211—81
116 METHODS OF COMMUNICATION FOR FOREST PROTECTION
with a flat, brass hook at one end and a cord terminal at the other. The latter has a
cord terminal at each end. The total weight is 10 ounces.
For use with the Adams hand set a similar connector may be made in the field 'of
emergency wire. A brass hook is easily improvised from the contact plates of a worn-
out 703 Ever Ready battery.
Fig. 69 Forest ranger using the No. 1-A emergency kit
The emergency connector, Northern Electric No. 311-D, used 011 some reserves,
is not as suitable as the new type, and this connector is no longer a, part of the standard
equipment.
2 — METHOD OF USE
The No. 311-D connector is joined to the overhead wire by throwing one end over
and then pulling it along the wire until a contact is made at the bare place in the
centre of the connector. The two ends are both joined to the line terminal of the set
marked L. The short wire is then used to join the ground termmal marked G to the
ground rod.
The standard connector is attached to the overhead wire by means of a short pole.
Generally, any light pole about 10 or 12 ft. long, cut as needed, is sufficient. To the
tip the end of the connector bearing the hook is attached, so that the hook projects a
few inches above the pole and the rest of the connector is wound around the pole in a
long spiral. It is then hooked over the wire and allowe,d to swing loose, the weight of
the pole serving to ensure a good contact The end bearing the cord terminal is joined
to the line post of the instrument, the short wire connects the ground post to the ground
rod. The whole operation is performed in a couple of minutes. With metallic circuits
two connectors must be used, but the ground wire is unnecessary.
3 — TEMPORARY GROUNDS
The importance of extreme care in locating permanent grounds has already been
emphasized. Ear less care is required for a temporary ground connection. Although
it is true that except in very dry regions, or in the winter in the north, a workable
ground for a temporary connection can be ebtained almost anywhere, yet it is always
THE MAGNETO TELEPHONE 117
best to let the grounding facilities determine the place of connection if possible. The
best place is the margin of a stream, pond, or slough, where the ground rod may be
set in the wet soil or mud. Do not try to ground in water alone, or in a Tocky bottom.
If a natural wet place is not convenient, ground in loose, moist soil and after setting
the ground rod pour a pail of water over it
The special portable ground rod, Northern Electric No. 313-B, usually known
as the bayonet ground rod (Fig. 62), is useful with emergency kits, but for use by
patrolmen with portable telephones it should be replaced by a large hunting-knife.
The bayonet rod is a singularly useless instrument except for its one special purpose,
and when weight is an important consideration, as with patrolmen or " smoke
chasers," the hunting-knife is preferable. A fairly large blade is necessary in order
to make a good ground. At the base of the blade close up against the handle a brass
binding-post should be inserted and soldered to the blade. The Cree knife shown
in Figs. 64 and 66 has a blade 9 in. long by 2 in. wide and serves admirably for
grounding a portable telephone, but a smaller knife may be used. Very good ground
rods -can be made of heavy jointed brass rifle cleaning rods, and these may be car-
ried in tne case of either of the portable telephones. It is probable that the need for
a satisfactory portable ground will result in development in this direction.
CHAPTER XIV
MAGNETO TELEPHONE
Section 84 — Introduction
It is a matter of common knowledge that the purpose of the telephone is to
enable conversation to be carried on between two persons who are beyond ordinary
talking distance from each other, and that this is accomplished by converting the
air vibrations of the voice into electrical vibrations which are carried to the distant
person over a wire or electrical conductor and there converted into air vibrations or
sounds of the same character. The modern commercial instruments have been
brought to such a high state of perfection and are so nearly " foolproof " that it is
possible for persons entirely without knowledge of the principles on which these
instruments operate to install and use them with entire success by observing a few
simplo precautions, following directions, and using plain common sense. It is very
desirable, however, that those who have charge of extended telephone systems, such
as are now commonly used in specialized forest protection, should have some under-
standing of the fundamentals of the telephone. Unfortunately, to understand the
operation of this instrument requires some knowledge of practically every branch
of electrical science, because nearly every branch is to some extent utilized in the
modern telephone. For the benefit of those desiring a full understanding of this
instrument a comprehensive list of books of reference has been inserted in Appen-
dix B.
The description of the telephone instrument contained in 'this manual is intended
•for those who have little or no knowledge of the science of telephony, and should
be regarded only as an introduction to this science.
It is necessary, however, to assume the possession of a knowledge of the funda-
mental electrical phenomena. Those unacquainted with even the elementary facts of
electrical science will first have to consult some standard text booK oil the subject.
Certain definitions, however, of technical terms most frequently employed in the
s-cience of telephony may assist in an understanding of the text, and are therefore
included in this manual.
118 METHODS OF COMMUNICATION FOR FOREST PROTECTION
Section 85 — Definition of Electrical Terms
(a) Voltaic Cell. — A voltaic cell is an arrangement of two electro-chemically dii>
fereiit solids in a liquid which will attack one of them more actively than the other.
This liquid is called the electrolyte and is generally an acid. One of the solids is
nearly always zinc. Carbon is very commonly the other. Dry voltaic cells usually
consist of a zinc cup containing a carbon plate and an absorbent porous substance
saturated with the liquid electrolyte. This cup is sealed with wax or asphaltum. Dry
cells are now commonly employed to furnish the current for the transmission of speech
by telephone. Inert dry cells that contain all the necessary elements except water
may be o'btained. They are entirely inactive until water is added and keep indefinitely,
while the ordinary type deteriorates rapidly even though not in use.
(fr) Conductor. — Any substance through which electricity flows readily is called
a conductor. Most metals are good conductors. In conductivity, copper is surpassed
only by silver and is followed by aluminium, zinc, iron, tin, lead, and carbon in the
order named. Iron has only about -one-sixth the conductivity of copper.
(c) Insulator. — Any substance through which electricity will not flow readily is
termed an insulator. " Non-conductor " or " dielectric " are other terms having the
same meaning. Among common insulators are ebonite, glass, resins, paper, paraffin,
porcelain, mica, rubber, and dry *air. " Conductor " and " insulator " are, however,
relative terms. No substance is an absolute insulator and all substances oppose some
resistance to the flow of electricity, so that no substance is a perfect conductor.
(d) Circuit and Grounded Circuit. — The entire path along which electricity flows
is called a circuit. It comprises the voltaic cell or cells called a battery or some other
device, such as a generator, for producing electrical pressure, and the wire or other
conductor connecting the battery plates or the ends of the generator coils. Bringing
the two extremities of the wire in contact and separating them are called, respectively,
closing and opening, or making and breaking, the circuit. A complete metallic circuit
is unnecessary, it being possible to use the earth itself as a return path for the current.
It acts more like a great reservoir of electricity than as a conductor. A circuit, part
of which consists of the earth, instead of being a complete metallic path, is called a
grounded circuit.
(e) Magnet. — A magnet is a piece of iron or steel (generally a bar) which has
the property of attracting other pieces of iron or steel. If freely suspended at it?
centre it will point north and south. It can impart these properties to another piece
of iron or steel without losing any of its own. These powers may also be -imparted to
a piece of iron or steel by passing an electric current through an insulated wire wound
around the iron or steel. Steel will retain these magnetic properties; very soft iron
will retain practically none. An iron magnet thus produced is called an electro-
magnet.
(/) Electro-motive Force — The Volt. — That force which maintains or tends to
maintain a current of electricity through a conductor is called electro-motive force.
The abbreviation for this term is E.M.F. Electro-motive force is, in effect, electrical
pressure and is analogous to the " head " or pressure which maintains a flow of water
through a pipe from one vessel to another at a lower level. Electricity flows in a con-
ductor only when there is a difference of such electrical pressure or difference of
"potential" between its own ends. Such a difference may be maintained by a voltaic
cell or t>y a generator. It is this difference of pressure which sets up a current in the
conductor, and as long as it is maintained the current will continue to flow. The
unit of E.M.F. is the volt, for practical purposes, about the E.M.F. of a Darnell's cell,
i.e., it is about the difference of potential between the zinc and copper plates of this
cell.
THE MAGNETO TELEPHONE 119
(g) Resistance — The Ohm. — The opposition offered by any substance to the flow
of the electric current through it is known as resistance. Different substances oppose
the flow of electricity in different degrees, copper being one that opposes a very low
resistance (see Conductor). Insulators oppose an immensely powerful resistance.
With any given conductor, increase in length causes increase in resistance; increase
in cross sectional area causes decrease in resistance; and, for most conductors, rise in
temperature causes increase in resistance. For any one conductor, resistance is, in a
way, analogous to the frictional resistance offered to the flow of water through a pipe.
Electro-motive force tends to maintain a flow of electricity against the electrical resis-
tance of a conductor just as a "head" of water tends to maintain a- flow of water
against the frictional resistance of a pipe. The unit of electrical resistance is the
ohm. Conductivity is the opposite of resistance.
(/&) Current Strength — The Ampere. — The rate of flow of electricity is termed its
current strength. It is the result of E.M.F. acting through a conductor and over-
coming resistance, and is measured in amperes. The ampere, or unit of current
strength, is analogous to the " miner's inch " used in the measurement of the flow of
water. Obviously the three factors, E.M.F. , resistance, a id current a:-e interdepend-
ent. Their relation to one another is stated in Ohm's Law thus : —
The Current is equal to the Electro-motive force divided by the Resistance, or
E
0 = -
R
(*') Electro-magnetic Induction. — Every magnet and every current-bearing wire
is surrounded by a magnetic field having among other properties that of being able to
induce magnetism in a piece of iron or steel placed within it, and of being able to
produce a difference of potential between the ends of a wire moved across such a
magnetic field in such a way as to cut its lines of force. If the ends of this wire are
connected outside the magnetic field, a current will flow as long as motion is main-
tained. Such currents are called induced currents and the process by which they are
produced is called electro-magnetic induction.
(j) Induction Coil.- — An induction coil is a device consisting of two distinct coils
of insulated wire, one placed around the other, but not electrically connected, by means
of which, as a rule, currents of low potential and high amperage are changed to a high
potential and low amperage, or vice versa. One of the coils, usually having an iron
core, is used to produce the magnetic field by means of a current from a battery to
which it is connected. This is called the primary. The other coil, generally above the
primary or around, it, is called the secondary. Currents may be produced in the
secondary by means of any of the following methods : —
(1) By moving either the primary or the secondary while a current is flowing in
the primary, thereby altering the position of the coils with respect to each other.
(2) By making or breaking the primary circuit.
(3) By altering the current in the primary.
(4) By reversing the direction of current in the primary.
(5) By moving the iron core while current flows in the primary, thereby altering
the magnetic field.
Any one of these operations causes a disturbance in the magnetic field as a result
of which currents are induced in the secondary.
In the induction coil, as usually employed, either alternating or interrupted
currents in the primary induce currents in the secondary whose E.M.F. bears the same
relation to the E.M.F. of the primary current as the number of the turns of wire in
the secondary coil bears to the num'ber of turns in the primary. For example, if there
120 METHODS OF COMMUNICATION FOR FOREST PROTECTION
are 10 turns in the primary and 100 turns in the secondary and a current of 1 ampere
at 10 volts pressure is passed through the primary, then the current induced in the
secondary will have a pressure of 100 volts but a current strength of only 0-1 of an
ampere. This principle is made use of in telephone transmission, in induction tele-
graphy, and in wireless.
(&) Electro-magnetic Generator. — The electro-magnetic generator is a device by
which induced currents are -produced continuously and made to now through an
exterior closed circuit. The dynamo generator consists of a magnet to produce a
magnetic field, and a coil of wire wound on an iron core, which latter part is called,
the armature. The armature is that part of the circuit in which the induced current is
generated. If moved in the magnetic field of the magnet in such a way as to cut its
lines of force, a current is produced by induction, and if the motion of the armature
is continuous the current that results is continuous also. Electro-magnets are usually
employed to produce a magnetic field but in some small generators permanent steel
magnets are used. Such generators are called magnetos and being extensively used in
certain types of telephones have given rise to the term " magneto telephone."
(Z) Direct Current and Alternating Current. — The electric current among its
other properties has direction. This has already been indicated in referring to the
production of induced currents as in an induction coil. A current which moves
continuously in one direction only is called a direct current. Such a current is that
which flows from the carbon pole to the zinc pole of a voltaic cell when these are con-
nected by means of a conducting material, such as a piece of copper wire. The current
used in ordinary telegraphy is a direct current. As contrasted with this form of
current we have that which is constantly changing in direction, flowing first m one
direction and then reversing and flowing in the other. This is known as an
alternating current and is produced by many forms of dynamo generators and in the
secondary of an induction coil. Alternating currents are especially important in tele-
phone work as both the talking currents and those which operate the common type of
polarized bell are of this character. So also, is the current which actuates the howler
used in vibratory signalling.
(m) Frequency. — This term is used to designate the rate of reversal of direction
of alternating currents. High-frequency currents are alternating currents that reverse
direction very rapidly, while low-frequency currents reverse comparatively slowly.
(n) Tension. — This term as applied to electricity has the same meaning as
potential difference or E.M.F. High-tension currents are those of high voltage or
E.M.F.
(o) Electro-static Induction. — An insulated conductor, such as a sheet of tin-foil,
has the property of receiving a charge of static electricity when subjected to an E.M.F.,
as, for instance, if it is connected to one pole of a cell, the other pole being connected
to the ground. The charge that it receives is of the same polarity as the terminal of
the cell to which it is connected and the amount of electricity held depends upon the
capacity of the conductor. At the same time it is always found that when a conductor
is charged as above described, an equal charge of opposite polarity is induced on the
bodies surrounding it. If two sheets of tin-foil, for instance, are insulated from each
other by means of a sheet of mica and one of them is charged as above, the other will
be found to have an equal charge of opposite polarity. This action by which bodies are
charged through an insulating medium is called electro-static induction.
(p) Condenser. — -A condenser is a device for storing static electricity. It consists
of two insulated conducting bodies separated from each other by an insulating material.
The common form of condenser used in telephone work consists of sheets of tin-foil
separated by sheets of paraffin-paper. However, any two insulated bodies, as, for
instance;, two parallel wires or a single wire and the surface of the earth, or the
TEE MAGNETO TELEPHONE 121
metallic conductor in a submarine cable and its protecting armour, act as condensers
and have a certain capacity or ability to receive an electrical charge depending on their
area, nearness together, and the character of the insulating medium between them.
Condensers act as a complete bar to the passage of direct currents. Alternating cur-
rents, however, will produce through a condenser the same effects as would be produced
were the condenser not in the circuit. This results from the inductive effect between
the plates of the condenser, and while there is no actual passage of the current through
the condenser the results produced where alternating currents are concerned are the
same as though the condenser were not in the circuit. The effectiveness of this action,
however, depends upon the frequency of the alternations and the capacity of the
condenser. High frequency arid large capacity produce better results than the opposite
'properties.
(#) Wire Measure, the Mil. — The mil is the unit of measurement for the cross-
section area of wires. It equals one one-thousandth of an inch (Hooo or -001 in.) The
circular mil is used as the unit of area for circular wires and the square mil for
rectangular conductors.
Section 86 — Parts of the Magneto Telephone.
A magneto telephone instrument such as is used on forest lines consists essentially
of seven parts, as follows: —
1 Receiver 4 Induction coil 6 Ringer
2 Transmitter 5 Generator (magneto) 7 Switch-hook
3 Battery.
To these are generally added a condenser wired in series in the receiver circuit,
and the whole is inclosed in a wooden case and wired with insulated copper wires.
Various accessory equipment is also employed. The more important of these
accessories are described in a following section of this chapter.
JL — RECEIVER
The first of the distinctive parts of the modern telephone to be invented was the
receiver. This was the invention of Prof. Alexander Graham ,Bell. For a time it was
the only one of the distinctive portions of the modern telephone employed, and served
as both transmitter and receiver. It exists to-day essentially as first invented, though
many minor modifications have been made in its construction, and it has ceased to be
regularly employed as a transmitter.
The common bipolar receiver consists of a horseshoe-shaped permanent magnet,
to each pole of which is attached a soft iron core, around which is placed a winding
of fine insulated wire. Both coils are joined in series and the two ends of the wires
are brought to binding-posts within or at the base of the shell to which the receiver
cord is attached. A small, thin, circular iron plate or diaphragm is held at a distance
of -015 in. in front of cores of the magnet coils and the whole is inclosed in a hard-
rubber case.
The receiver when used as a transmitter is essentially a miniature dynamo. The
vibrations of the diaphragm, caused by the sound waves that impinge upon it, pro-
duce disturbances of the magnetic field surrounding the poles of the permanent mag-
nets and thus generate minute currents in the coils which flow out over the line and
cause similar disturbances in the magnetic field of the magnets at the other station.
These, in turn, produce vibration of the diaphragm similar to those that produced
the currents1 originally, and these vibrations cause sound waves which reproduce the
sounds made in the first instance. The currents that may be produced in this way,
however, are extremely minute and have not sufficient pressure to operate success-
fully over long lines of high resistance. The receiver, therefore, is not ar efficient
122 METHODS OF COMMUNICATION FOR FOREST PROTECTION
, fit
Fig. 70 Bipolar hand receiver
Fig. 71 Longitudinal section of bipolar receive!'
Fig. 72 Diagram of telephone circuit, first stage
TEE MAGNETO TELEPHONE 123
transmitter. It is immensely sensitive to small currents, however, being in this
respect one of the most amazing instruments that has ever been produced. As an
instance, it may be stated that experiments have shown that the work performed by
a weight of only one pound falling through a vertical distance of one foot would
involve sufficient energy to maintain an audible sound in a receiver continuously for
about 250,000 years.
In its most primitive form, therefore, a telephone consists simply of two receivers
joined together by a wire of some conducting material, as in Fig. 72. This largely
explains 'how, as most operators of telephone circuits have learned, speech may often
be transmitted through the receiver of the ordinary instruments when the transmitter
itself is out of order.
The modern receiver is an extremely simple instrument and almost immune
from serious injury. Only gross carelessness can result in a broken shell or bent
diaphragm, and this is generally the extent of any damage to a receiver. Only very
rarely do the coils become burned out by lightning, or the permanent magnet become
unduly weakened through loss of magnetism.
The receiver cord by which it is connected to the telephone may cause trouble.
It must be extremely flexible, and is therefore made of insulated tinsel wires. These
sometimes. break, especially where they join the tips, thus introducing a fault into
the circuit.
2 — TRANSMITTER
The limitations of the magneto telephone as a transmitting instrument soon
started investigators working on the production of a more efficient transmitting device.
The need of a stronger current than can be generated by the magnetic field of the Bell
instrument was apparent, and the solution was found in the modern carbon microphone
or transmitter. This instrument is based on the principle early set forth by Du
Moncel that, " if the pressure between two conducting bodies forming part of an
electric circuit be increased the total resistance of the path between them will be
diminished, and if the pressure be decreased there will be an increase in the
resistance." Other investigators showed that a loose contact was an important
feature in securing the necessary variations in resistance to cause variation in current,
so that the problem became one of contriving some device by which a conducting
material forming part of the telephone circuit might afford a. loose contact, the
pressure on which could be varied by the sound waves produced by the voice and
thereby through the varying resistance resulting, vary the current through the con-
ductor. This varying current passing out over the line to a distant receiver would
cause corresponding variations in the magnetic field surrounding the cores of the
receiver magnet coils', and these in turn acting on the receiver diaphragm would
cause it to vibrate and thus produce sound waves similar to those originally produced
by the voice.
It was further discovered that, of all conductors, carbon was the one in which
slight variations of pressure produced the greatest effect on the current. Carbon was,
therefore, adopted as the material out of which to make one or both of the electrodes
which formed the loose contact in the circuit.
In the magnetic telephone no battery is required but, as previously explained, the
currents produced are extremely minute. With the microphone in the circuit, a
battery may be employed and a current of much greater strength obtained. This
current, the microphone, through the loose contact of the carbon electrodes, varies
according to the varying pressures produced by the sound waves, and as the strength of
the current varies, so also varies the tension between the diaphragm and receiver
magnet at the distant station whereby the diaphragm is caused to vibrate and repro-
duce sounds as- previously explained. The transmitter most commonly employed in
America and the one used on the Forestry (Branch standard equipment is known as
the White or " solid-back " transmitter and is shown in Figs. 73 and 74. In this
124
METHO'DS OF COMMUNICATION FOR FOREST PROTECTION
transmitter two carbon disks are employed! between which is a quantity of carbon
granules. To one of these disks a light metal diaphragm is attached. This diaphragm
is caused to vibrate by the sound waves impinging upon it, thereby varying the pressure
Pig. 73 Solid-back transmitter and transmitter arm
Fig. 74 Details of the solid-back transmitter
Line
1
p
Trans •
3
||||_^
dtdW
*3Ilr
(J UJ
Trans.
r//
Fig. 75 Diagram of telephone circuit, second stage
on the carbon granules between the two carbon disks. The transmitter is so wired that
these disks and the granules between them are in the battery circuit. The vary ing-
pressure, therefore, causes variations in the current which in passing through a receiver
reproduces the sounds of the voice.
THE MAGNETO TELEPHONE 125
The next step, therefore, in the development of the telephone circuit consisted in
th.e introduction into it of a voltaic battery and a carbon microphone or transmitter
as shown in .Fig. 75.
The back electrode B is a small metal case held to the support A by a lock screw.
It carries in it the metal plate :C, which bears a carbon face. Over this is a similar
plate D and between the two is placed a quantity of carbon granules. The plate D
carries the screw-threaded bars E and G. Over these fits the mica washer F, the nut IT,
and the screw-cap I. The bar G projects through the vibratory diaphragm J, which is
held in place by the nuts S and S.
The transmitter is perhaps the .most delicate portion of the modern telephone set.
It is readily burned out by atmospheric electricity, and the carbon granules sometimes
pack together, especially if they become damp, thus interfering with transmission. Xo
one but an expert instrument man should ever undertake to repair an injured' trans-
mitter.
3 — BATTERY
For telephone service what is known as an open-circuit cell is preferred as a source
of electric current for talking purposes. As a rule a battery of two or three such cells
is used. It might seem that transmission could be improved by the use of a very strong
current, but the difficulty arises that such currents heat the carbon contact in the
transmitter, and, in time, ruin it. For this reason low-resistance, low-voltage batteries
are preferred.
Open-circuit cells are those which have the power of recuperating through
depolarization whenever the circuit is left open. They are not suitable for prolonged
continuous use, as are closed-circuit cells, which work best when in constant use. As
will be later explained, the talking circuit of a telephone is always open except when
the telephone is in use or the receiver off the hook and, therefore, open-circuit cells are
the best for this service. The greater convenience of dry cells has led to their general
adoption for telephone purposes. These are in all respects like ordinary cells except
that the liquid solutions are mixed with some absorbent material and so rendered
practically solid. There is thus little danger of liquids spilling or leaking out and
causing damage. At the same time this danger is not entirely absent and batteries
should never be carried in telephone sets, especially when lying on their sides. In this
position, if there is any defect in the shell of the battery, some of the contents may leak
out and corrode the wiring and other metal parts with which they come in contact.
Dry cells, of course, become exhausted in time and must be renewed just as do other
forms of primary cells.
4 — INDUCTION COIL
The next important step in the development of the telephone after the invention
of the transmitter was the introduction of an induction coil into the circuit 'by Edison.
This, in fact, marked the beginning of practical telephone development, since, prior
to the use of an induction coil, the range of transmission was extremely limited. Even
after the transmitter was employed, it was found that the changes produced in the total
line resistance by the varying pressure on the carbons were so small in comparison t<
the total line resistance as to produce variations in the current that were scarcely per-
ceptible in a distant receiver. The problem, therefore, was to arrange some means by
which the voltage of the current going out over the line could be increased, other than
by increasing the voltage of the battery, which we have already seen had
limitations.
It had further been noted that the telephone receiver was more sensitive to minut
alternating currents than to the varying- direct currents such as had up to this
been employed, but no means by which an alternating current might be employee
been devised.
126
METHODS OF COMMUNICATION FOR FOREST PROTECTION
The induction coil, as used in the telephone, accomplishes both of these objects.
It is, of course, a fundamental factvof electrical induction that any change in a current
in the primary winding of an induction coil, such as the opening or closing of the
circuit, or the increasing or decreasing of its strength either by changing the voltage
or the resistance, induces a momentary current in the secondary winding. These
momentary induced currents are in 'the same direction as the current in the primary
Pig. 76 Telephone induction coil
Line
flee
Rec
Battery
Fig. 77 Diagram of telephone circuit, third stage
when caused by a decreasing of the primary current, and in the opposite direction when
caused by an increase in that current. Now the effect of the varying pressure on the
carbon granules in the transmitter is to alternately increase and decrease their resist-
ance, thereby alternately diminishing and increasing the strength of the current flowing
through them; and if the primary of an induction coil is introduced into the circuit
with a transmitter and a battery, the momentary currents induced in the secondary of
this coil will alternate in a similar manner according to the law of induced currents'.
Thus, the desired alternating current is secured.
Moreover, the voltage of these induced currents is very greatly increased. This
depends upon the construction of the induction coil itself, the rule being that the
voltage of currents in the secondary bears the same relation to the voltage of the
primary current as the number of turns in the secondary winding bears to the number
in the primary. Thus, if the primary winding consists of 100 turns and the secondary
of 2,500, the voltage of the secondary currents will be 25 times that of the primary.
Since, as has already been explained, the receiver is sensitive to currents1 of quite
minute amperage, a high voltage that will enable the current to overcome line resist-
ance rather than a high amperage and low voltage is desirable.
The part played by the induction coil in the modern telephone is of immense
importance since, as has been stated, its use marks the beginning of practical long-
THE MAGNETO TELEPHONE 127
distance transmission. In brief, it accomplishes three things, all important to suc-
cessful telephone operation: —
(1) It produces true alternating currents in place of the direct current of vary-
ing intensity produced by the transmitter and battery alone.
(2) It produces currents of much higher voltage (E.M.F.) than it is practicable
to secure from voltaic cells operating through carbon transmitters alone.
(3) By limiting the circuit over which the current from the battery flows, to
the very short one including only the battery itself, the transmitter, and the primary
of the induction coil, and by making the last of low resistance, the variations in
resistance produced by the varying pressure in the transmitter under the influence
of sound vibration are in comparison to the entire resistance quite large. These
impulses are impressed upon the secondary current with an increase in strength and
amplitude corresponding to the increased pressure of that current, and are success-
fully transmitted out on the line to the receiving stations over very great distances.
The telephone circuit as produced by including in it an induction coil is shown
in Fig. 77. This shows diagrammatically the circuit of the speech-transmitting por-
tion of the telephone substantially as it exists to-day. The rest of th^ telephone set
is required for signalling and is only incidental to the portion employed in trans-
mitting the sounds of the voice.
5 — MAGNETO GENERATOR
The generator is simply a small dynamo. It differs from the large dynamos
used in generating power and light currents only in having permanent steel mngnets
Fig. 78 Magneto generator, five bar
in place of the usual electro-magnets. Generators in modern telephones are of
various sizes, depending on the kind of service for which they are intended. The
largest and most powerful are built with five magnets (five-bar generators) and are
the type used in the Forestry Branch standard instruments. They are intended to
ring through very high resistances, such as 'are encountered on forest telephone lines,
128 METHODS OF COMMUNICATION FOR FOREST PROTECTION
and for the size of the machine are extremely powerful and efficient generators of
electric currents. They produce true alternating currents at about 65 to 75 volts and
a frequency of 15 cycles per second, are very compactly built, and are not very
likely to give trouble.
The two principal parts of the generator are the magnets and the armature.
The former are horseshoe-shaped and are made of a high quality of steel, and strongly
magnetized. Between the poles of the magnets is placed the armature. It consists
of an H-shaped laminated iron core around which is wound a coil of fine insulated
wire. A small crank with gear wheels is used to rotate the armature at a high rate
of speed between the poles of the magnets, thus producing the current. It will be
apparent, however, that since the generator serves only to produce current for ring-
ing purposes there is no reason why it should be permanently in the circuit. On the
other hand, there are certain objections to such permanent connection. The arma-
ture winding if permanently bridged across the line would form an additional path
to ground, thus reducing the current available for ringing other instruments. Also,
injury from outside currents might occur which can be avoided if the armature is
disconnected while it is at rest. For these reasons the magneto generators are usually
arranged with an automatic circuit-breaking device, by which the winding of the
armature is thrown out of the circuit whenever it is 'at rest and is thrown into the
circuit by the act of turning the generator crank. It will be noted that as soon as
the crank on the standard instrument is turned it slips inward a fraction of an inch.
This slight movement serves to close the circuit and throw the coil of the generator
armature on to the line, thus permitting the current from the. generator to flow out
over the line to ring the bells at the distant stations.
6 — KlNGER
The low-frequency alternating current from the magneto generator operates a
polarized bell or ringer (Fig. 79) at each station by means of which the attention of the
Fig. 79 Polarized ringer, unbiased type
distant station is secured. Code ringing is employed on forest lines exclusively; that
is, each station has its own signal or call letter made by a combination of long and
TEE MAGNETO TELEPHONE 129
short rings, and, although the bells at all stations on the line ring whenever the genera-
tor is turned at any one of them, yet, by employing a code, only that station responds
whose code signal is sounded. The polarized bell consists of two coils of fine wire,
(see L,Ll Fig. 96) with soft iron cores held between -the poles of a U-shaped per-
manent magnet, NIS by being attached to S. This has the effect of prolonging the S
pole so that the opposite ends of the coil cores have S polarity. Across one end of
this pair of coils is a soft iron armature F pivoted at its centre by the screw E. To
its centre is attached a slender rod H ending in a small metal ball between the two bells
K,K1. Armature F under the influence of the adjacent magnet acquires S polarity
at the centre and N polarity at each end. The armature in this condition is attracted
equally to both cores and rests against one or the other as it may happen to stop. The
coils, however, are connected in series and wound in opposite directions. If, then, a
current passes through them it will tend to increase the strength of one pole, and to
decrease the strength of or change the polarity of the other. Thus, if L is strengthened,
LI will be weakened and the armature F will be attracted to L, causing the clapper
II to strike the bell Kl. However, the current being an alternating one, the changes
in the strength of the poles will take place first on one side and then on the other alter-
nately as the current moves, first in one direction and then in the other. As already
stated this takes place fifteen or more times per second, according to the frequency of
the alternations of the current from the generator. The clapper H therefore is caused
to vibrate very rapidly, striking the bells at each vibration and causing an almost
continuous ringing sound.
For bridging service as used on forest lines, ringer coils are wound to a resistance
of 1,000, 1,600 or 2,500 ohms. The standard Forestry Branch instruments and exten-
sion bells have 2,500-ohm ringers. Such high-resistance ringers are employed on
heavily loaded lines for the purpose of preventing the escape of current through the
ringer circuit of the numerous instruments attached to the lines. These high-resis-
tance coils, which are generally bridged permanently across the line, are wound so
as to give a very high magnetic retardation, and, although readily operated by the
low-frequency currents from magneto generators they are effectual blockades against
the high-frequency current of the talking circuit. The higher resistance also is a con-
siderable aid in signalling, since it operates to reduce the amount of current that is
diverted to the ground at each instrument and therefore increases the number of
instruments that may be rung on a given line. It must be noted in this connection,
however, that all ringers on the same line must be wound to the same resistance, as
otherwise the low-resistance ringers will tend to prevent the others from receiving
the proper amount of current.
In some instruments the ringer is thrown out of the circuit while the telephone
is being used for talking. This is not the case, however, in the standard Forestry
Branch instruments. But, although the ringers in these instruments remain perman-
ently bridged across the line at all times, their high resistance effectually bars out the
talking current, so that this current passes through the receiver to the ground in the
instruments in use and not through the other path offered through the ringer coils.
It will also 'be noted in the diagram of the wiring of the standard telephone
(Fig. 97) that when the generator of any station is being used to ring another station,
two paths are available to the current, one through the line wire to the distant station,
thence to the ground, and back to the generator whence it came; the other through
the ringer of the calling station itself. By this means a portion of the ringing current
is shunted through its own bell and this bell is rung the same as are all other bells
on the line. The advantage of this arises from the fact that the ringer is particularly
liable to trouble due to several causes. It may, for instance, fail to ring owing to
improperly adjusted bells or armature, or to coils being burned out by lightning, or to
faulty connections in the ringer wiring, or to a short circuit on the line .or in the
protector. Such trouble is immediately noted as soon as an attempt is made to ring
a distant Nation when the bells are permanently connected across the line:
79211—9
130
METHODS OF COMMUNICATION FOR FOREST PROTECTION
7 — SWITCH-HOOK
It has be«ni previously indicated that there are two entirely different sources of
electric current in a magneto telephone set. The one is the local battery; the other is
the magneto generator. The current from the local battery traverses a very short circuit
Fig. 80 Telephone switch-hook
through transmitter and primary of the induction coil only, but induces a secondary
current in the induction coil which traverses the whole line, thus enabling conversation
to be carried on. The current from the magneto generator flows out over the line,
also, and actuates the bells at all other stations for signalling purposes. When the
instrument is not being used it is obviously undesirable to have the parts used for
talking connected to the line. If this continuous connection existed, conversation
between any two stations would be heard at all other stations and as part of the
talking current would pass through each receiver connected to the line the amount
received by any one of them would be proportionately reduced. The leakage through
the low resistance of the numerous receivers and induction coils, moreover, would
make signalling impossible over long lines with numerous instruments. Furthermore,
the continuous current that would flow through the transmitter circuit would quickly
exhaust a battery of the open-circuit type such as is used in the telephone. Accord-
ingly, in all telephones a device is installed by which the talking circuit is cut off from
the line when not in use and the transmitter circuit is opened. This is accomplished
by the switch-hook which is so arranged that when the receiver, which ordinarily is
suspended from it, is removed, the talking circuit is automatically thrown into the
line. Conversely, when the receiver is placed back on the hook, the depressing of this
hook opens the circuit. A large number of devices for accomplishing this have been
invented. The one shown in Fig. 80 is the type employed in the Forestry Branch
standard instruments in wall sets and desk sets. In hand sets such as the 1375-A or
the 1004-A portable instruments, push-button devices are. used to accomplish the same
result. It is well, perhaps, to note that in case one of these push-buttons is depressed
for any long period, the small battery of the portable instrument is very likely to
become exhausted. This sometimes happens with the 1375-A hand set where the
push-button projects proi linently from the side of the hand set and when packed for
TflE MAGXETO TELEPHONE
131
transportation with the receiver cord wound around it, it sometimes is depressed for a
long time. Most of the trouble with exhausted batteries in this set is probably due to
failure to guard against this accident.
8 — ACCESSORY EQUIPMENT
In addition to the essential parts of the telephone previously described there are
several pieces of apparatus generally used on forest lines about which it is desirable
that some information be available to those in charge of such lines.
These include the following : — .
(a) Condenser
(b) Howler
(c) Lightning-arrester or -protector
(d) Switches
(e) Repeating coils
(a) Condensers. — If two conductors, preferably in the form of thin plates such as
layers of tin-foil, are placed close together with a non-conducting material or dielectric
between them so that they are nowhere in direct contact and are then connected, one
to each pole of a voltaic cell, it will be found that a certain amount of current will
ROLLED CONDENSER
Me. 21-
CAPACITY 3L W. F.
Fig. 81 Rolled condenser
flow from the cell to the plates until they become fully charged with static electricity.
Such a device is called a condenser. The ability of an arrangement of this sort to
receive an electric charge, generally termed its capacity, varies in direct proportion
to the area of the plates, inversely as the square of the distance between the plates, and
directly as the specific inductive capacity of the dielectric. It is not essential that
the conductors be in the form of plates, however. Any two surfaces, such, for
instance, as the surfaces of two telephone wires placed parallel to each other and
insulated from each other as on a metallic pole line, will act in the same manner. So
also will a single wire line, the earth's surface forming one plate, the wire the other,
and the air between them acting as the dielectric. A great many of the difficulties
encountered in securing good telephonic transmission are caused by this electro-
static capacity of the line. This, however, is aside from the subject of condensers as
exemplified in the accessory equipment of the telephone.
It was previously stated that if the talking circuits of the various instruments
on a line were left in the circuit continuously instead of being cut out by the switch-
hook when the receiver is hung up, it would be impossible to ring up the stations on
the line, owing to the leakage of the calling current through the receiver circuit. The
same thing takes place when on party lines a number of receivers are taken off the
iooks by persons " listening in." Signals could not be transmitted over such lines
79211— 9
132 METHODS OF COMMUNICATION FOR FOREST PROTECTION
when several persons are " listening in," were it not for the use of a condenser in the
receiver circuit. All standard Forestry Branch instruments are thus equipped, the
wiring being as shown in Figs. 41 and 97.
The condensers used for this purpose consist of alternate strips of tin-foil separated
from each other by waxed paper. They have a capacity of half a microfarad. A
condenser acts as a complete bar to the passage of direct currents, or, in other words, it
constitutes an open circuit. To alternating currents, however, it offers a more or less
perfect path depending on the character of the current, particularly its frequency and
the capacity of the condenser. The condensers used in the standard instruments readily
permit the passage of the high-frequency currents of the talking circuit but bar out the
low-frequency currents of the calling circuit almost completely. It is thus made
possible to ring through, even though a considerable number of receivers may be off the
hooks.
Fig. 82 Howler
Similarly, a condenser is used with the howler where vibratory currents are
employed in signalling as with the 1004-A hand set. These vibratory currents are
alternating currents of very high frequency which readily pass through the 1-micro-
farad condenser, wired in series with the howler. This condenser, however, effectively
prevents the escape to the ground of the low-frequency alternating currents of the
magneto generators, so that both types of signalling devices may be used on the one
line without short circuiting or interference.
(fr) Howler. — For the purpose of reducing the weight of the portable instruments
as much as possible it was necessary to do away with the heavy magneto generator.
THE MAGNETO TELEPHONE
133
This was accomplished in the 100-i-A hand set by using for signalling an induced
current of high potential and high frequency acting upon a special typs of telephone
receiver at the distant station. The wonderful sensitiveness of the receiver to small
currents of this kind has previously been explained. By this system, therefore, it is
possible to work over very faulty lines where the ordinary generator currents are
entirely lost through leakage or high resistance. The howler is the special form of
receiver used to receive vibratory signals. It is the same aa the ordinary receiver
already described except that the pole pieces of the long, horseshoe magnet are
"attached to it at right angles. This is mounted in a wooden block for convenient
attachment to the wall and is prov:dei with a small megaphone which serves to con-
centrate the sound waves given off by the vibrating diaphragm. Howlers are con-
nected between the telephone »and the protector so that they are protected from injury
by lightning or other high-tension currents andv are not likely to get out of order.
They must be carefully adjusted so as to produce the maximum sound, the adjust-
ment being accomplished by tightening or loosening the screw-cap which holds the
diaphragm in place. The type of howler used by the Forestry Branch is shown in
Fig. 82.
(c) LigJi-tning-arrester. — It is always necessary to protect telephone instruments
against lightning. This is particularly true on many long-d'istance forest lines which
cross through regions of high altitude where lightning is sometimes very prevalent.
It is also necessary to provide special protection wherever telephone lines are liable
Fig. 83 Lightning protector for use where there are no power
or light wires
to come iii contact with wires bearing electric-light or power currents. Two types
of protective devices are employed. In the lightning-arrester used by the Forestry
Branch advantage is taken of the fact that a high-tension current such as lightning
will jump a small air gap in seeking the shortest path to the ground rather than pass
134
METHODS OF COMMUNICATION FOR FOREST PROTECTION
through the long coils of the telephone ringer or other parts of the set. This arrester
(Fig. 83) consists of a suitable insulating block A on which 'are placed two pairs of
copper blocks B, B1 held together by springs but not in direct contact with each other
because of a thin sheet of mica placed between them. A brass bar extends from
binding-posts 0 and C1 to the copper blocks nearest them. A similar bar extends
from the inner blocks to binding-post D. The line wire is connected to post C and the
ground wire to post D. To all ordinary telephone currents the air gap between the
copper blocks is an effectual bar. Dust collecting between the blocks caus2S a short
circuit but is largely prevented from accumulating by the brass covering cap E. By
Fig. 84 Protector with fuses, for use where there
are power and light wires. Note
method ' of binding edge of asbestos
mat with metal tape
a lightning current, however, the path to the ground across the air gap is taken in
preference to that through the instrument, and in this way such currents are success-
fully prevented from damaging the telephones.
The effect of lightning-arresters on high-tension currents other than lightning
is somewhat similar, but these currents are very likely to be continuous instead of
merely momentary as are lightning currents. A " cross " with such a current would
therefore result in a constant sparking across the air gap of the protector, which
would almost certainly cause a fire if it did no other serious damage. To prevent
THE MAGNETO TELEPHONE 135
this a line fuse must be introduced1 in the line between the protector and the outside
wires. This fuse contains a short length of easily fusible metal which melts when-
ever a current of greater strength than the fuse is designed to carry comes over the
wire. The circuit is thus opened and damage by sparking is prevented, as the air
g»ap through the fuse is entirely too large for any ordinary high-tension current to
jump. Fig. 84 shows a protector designed to guard against both lightning, and power
and light currents which has bean adopted by the Forestry Branch for use wherever
both kinds of dangerous currents are encountered.
This means that on many reserves all instruments must have the combined light-
ning and high-power protector, because no matter on what part of the circuit a power
line is encountered it is necessary that all instruments oil that circuit be fully protected.
Fig. 85 Baby knife-switches. (A) Single pole, single throw (S.P.S.T.). (B) Double pole,
double throw (D.P.D.T.)
(J) Switches. — For convenience in separating a branch line from a main line,
for cutting off stations not in use, for dividing extra long lines into shorter sections,
and for other similar purposes, it is frequently necessary to install switches in telephone
circuits. As the currents carried are all comparatively weak, no very elaborate
switching devices are needed, and a simple, inexpensive form of knife-switch is found
to serve all purposes adequately. Those mounted on <a porcelain base as shown in
Fig. 85 will be found most satisfactory. They are fastened in place with round-head,
blued screws of suitable gauge and length.
Switches of this kind are classified by the number of poles either as single, double,
triple, etc. They are also further divided into two classes, depending on whether they
make one contact or two. Those making but one contact are called " single-throw "
(S.T.); those 'making two, "double-throw" (D.T.). For most purposes a single-pole,
single-throw switch ('S.P.S.T.) is sufficient (see Fig. 85). Where more complex con-
nections are involved various multiple-pole switches of either the S.T. or D.T. type
may be required. It is always to be remembered in placing switches that the more
connections that can be made or broken by the movement of one switch, the less
likelihood there is of confusion in operating the switchboard. Switchboards should
always be designed, therefore, to simplify as much as possible the movements required
by using multiple-pole switches wherever feasible.
(e} Repeating coils. — These are simply a special form of induction coil generally
employed for the purpose of preventing the unbalancing of metallic lines when joining
grounded lines to them. While it is possible to neutralize inductive disturbance on
metallic lines by proper transposition, this effect is lost if a grounded line is joined
directly to a metallic line without interposing a repeating coil. By inserting a repeating-
136
METHODS OF COMMUNICATION FOR FOREST PROTECTION
coil in the circuit, direct metallic connection between the two lines is avoided, as each
is joined to a separate winding of the coil. Transmission, therefore, through the coil
is accomplished by induction and if desired it may be accompanied by a stepping-up
or a stepping-down of the voltage in passing from one line to another. A great many
repeating coils, however, do not alter the voltage, but have both windings of the coil
alike.
Protector
Protector
tc C/rct/if f s~\ \ /
Von [\Q) {
Sec ft on
Repecrfing Co//
Fig. 8'6 Method of inserting a metallic circuit section in a grounded line to overcome
induction disturbances
Fig. 87 Diagram of a phantom circuit
To connect a grounded and a metallic circuit through a repeating coil, both wires
of the metallic line are joined to the ends of the same winding of the coil. The single
wire of the grounded line is then joined to one end of the other windings, the second
end being grounded. By using two such coils, a grounded line may be transformed
into a metallic line through a noisy portion of the length, and all foreign noises
perfectly eliminated. This method of connection is shown diagrammatically in
Fig. 86.
THE MAGNETO TELEPHONE 137
The standard Forestry Branch repeating coil is a special type adapted so that
it may be used for several purposes. In this coil there are four independent wind-
ings, each with a pair of outside terminals. By joining two pairs of these windings
together by jumpers1 between the proper terminals, as shown in Fig. 56, a repeating
coil of two independent windings is secured, which may be used for the purpose
above described. This arrangement of coils, however, also makes possible the making
of a connection to the exact centre of either one of the two windings, since each is
composed of two separate but similar windings joined by an external jumper. Such
a connection to the centre of one of the windings of the repeating coil is shown in
Fig. 56 by the heavy line leading from the terminal marked 3 and labelled " To
Phantom." The coil, therefore, may also be used to secure two distinct telephone
circuits from a single metallic line as shown in Fig. 87. In this figure the circuit
A B is metallic with a repeating coil at each end. Transmission between the through
stations A and B over the metallic line takes place inductively through the two coils.
Each coil consists of two windings. Winding 1 is similar to 4; winding 2, to 3.
The second circuit C D is taken off from the centre of winding 2 and winding 3,
thus assuring that the resistance in the coil on both sides of the point of connection
is the same at each end. To work perfectly the ohmic resistance of the two line
wires must also be equal. It will then be apparent that current entering at 2 from
station C will divide evenly at 2 and pass over both wires to the coil at station B,
where it will again unite and pass through D to the ground. At any intermediate
station such as E, for instance, no effect will be noticeable, because since both wires
carry an equal current with no difference of potential there is no tendency for cur-
rent to pass from one to the other and therefore it cannot flow through the apparatus
at station E. The circuit taken out of the centre of the coils at 2 and 3 is called a
" phantom " circuit and by its use two distinct independent circuits, one grounded,
the other metallic, may be secured from a single pair of wires. Similarly three dis-
tinct metallic circuits may be secured from two pairs of wires, and various other com-
binations whereby several independent telephone circuits may be superimposed on
the same wires are possible.
Section 87 — Methods of Connecting Telephones to Line
Forest protection telephone systems are always party lines; that is, there are a
greater or less number of instruments all connected to the same line at different
stations between its terminals. There are two general systems employed for con-
necting up the instruments on a party line of this kind : the series system and the
bridging-bell system. Of these, only the bridging-bell system is of any use on forest
lines and, in fact, the series system is now little used for any purpose.
1- — SERIES SYSTEM
This is the oldest method of connecting1 .the several instruments on a party line,
but is now so little used and is so inapplicable to forest-protection telephone lines that
only the briefest consideration is desirable. The method of connection is fully illus-
trated in Figs. 88 and 89, the first of which shows a series connection on a metallic
circuit and the second a series connection 011 a grounded circuit. It will be easily
seen from these diagrams that the talking current between any two telephones on the
line has to traverse all the bell coils of the intermediate telephones1. These, there-
fore, must be wound to very low resistance, generally about 80 ohms, and even then
the current is so weakened by the combined effects of resistance, impedance, induc-
tion, and leakage that speech transmission i?1 impracticable except over a short line
with relalively few telephones connected to it.
138
METHO'DS OF COMMUNICATION FOR FOREST PROTECTION
o
00
00
00
Fig. 8-8 Telephones connected in series on a metallic line
A/a//? /me
Protector
00
oo
oo
Fig. 89 Telephones connected in series on a grounded line
2 — BRIDGING-BELL SYSTEM
For the purpose of overcoming the difficulties inherent in the series system the
bridging or multiple method of connection was adopted and is now the standard
method of connecting up party lines isuch as are employed in forest protection. All
the standard instruments of the Forestry Branch are wired for this system only, and
all lines installed are of the bridged type either grounded or metallic. The method of
connecting the telephones to the line by this system is shown in Figs. 90 and 91, the
THE MAGNETO TELEPHONE
139
first being a bridged, grounded circuit and the second a bridged, metallic circuit. In
this system, as will be seen from the figures, each instrument is on a separate leg from
the line to the ground or on a " bridge " between the two wires of a metallic circuit.
oo
00
oo
oo
Fig. 90 Connecting bridging telephone on a grounded line
OO
00
Fig. 91 Connecting bridging telephone on a metallic line
The bells of bridged telephones are constantly in circuit and each instrument,
therefore, at all times forms a separate path for tooth talking and ringing currents to
the ground or the return wire. It will, therefore, be evident that with low-resistance
bell coils the line resistance between instruments, except on very short lines, might
140 METHODS OF COMMUNICATION FOR FOREST PROTECTION
easily be iseveral times as great as the resistance of the coils, and the bulk of the cur-
rent would, therefore, be shunted. to the ground through the bells of the nearest instru-
ments and would not reach the more distant instruments in sufficient amount' to ring-
them. Bridging bells, therefore, are wound with coils of very high resistance —
2,500 ohms in the Forestry Branch instruments — only by this means the ringing cur-
rent is made to traverse the entire line and only enough passes to the ground through
each bell to ring it properly. These high-resistance bell coils also effectively bar out
escape of the talking current. Although this is not so much the result of their resis-
tance as it is of the impedance resulting from the peculiar construction of these coils,
it is thoroughly effective in confining the talking current to the line and preventing
leakage to the ground through the bells which are, as stated, continuously in circuit on
all instruments. The importance, however, of having all coils of the same resistance
will be evident, since the introduction of a low-resistance 'bell will divert to the ground
an excess amount of current to the detriment of all other instruments on the line.
CHAPTER XV
OPERATION
Section 88 — Operating Rules
On every telephone system there should be a definite set of rules to govern the
operation of the lines and stations. These are usually very simple and should be
made up in the form of a printed or typewritten card and fastened to the wall close
beside the instrument, or directly over it on the post or tree support in case of out-
door stations. This card should also contain a complete list of all stations and call
signals on the line and directions for getting connections through central switching1
stations to other lines if necessary. All such switching stations should be mentioned
with the points to which connections may be had through them. In many cases,
instruments are used by persons not connected with the fire-protection staff to send
news of fires or other messages during the absence of the ranger, or from a field1
station. Operating rules should be framed to en-able such persons to use the telephone
Hine without difficulty or delay.
In all cases rules for operation should provide against persons " ringing in " on the
line when it is in use and for " ringing off " when through using the line. Two rules
to cover these provisions are: —
1 Before ringing any station, " listen in " on the line and inquire if the line is
busy. Do not ring while the line is in use by others.
2 On finishing a conversation, both stations must ring off by giving one short ring.
Section 89 — Code Signalling
1 — METHOD EMPLOYED
The calls of various stations are made by long and short rings variously arranged.
As a rule not more than four such rings need to be included in any one call or signal.
Those stations which are called most often should have the most simple signals and
those called least often, the most intricate. It must be noted, however, that " longs ;r
transmit somewhat better than "shorts" over lines that are in poor condition, so that
-distant stations should, as a rule, have signals largely made up of long rings while the
OPERATION
141
nearby stations should have signals composed of " shorts." The assumption, of course,
is that most of the calls originate at one end of the line as, for instance, at a super-
visor's headquarters.
For the "ring off" signal, one short ring will be found most satisfactory.
For the main headquarters, one long ring is generally preferred.
2 — LIST OF BELL CALLS
The total number of possible signals made up of not more than four rings is
thirty. If five rings are used, a total of sixty-two signals may be employed but thirty
generally suffice. These thirty signals are shown below : — •
1 One short
2 One long
3 Two short
4 Two long
5' One short, one long
6 One long, one short
7 Three short
8 Two short, one long
9 One short, one long, one short
10 One short, two long
11 One long, two short
12 One long, one short, one long
13 Two long, one short
14 Three long
15 Two long, two short
If)' One long, one short, one long, one
short
17 One long, two short, one long
18 One long, one short, two long
19 Two long? one short, one long
20 Three long, one short
21 Four long
22 One long, three short
23 One short, three long
24 One short, two long, one short
25 One short, one long, one short, one
long
26 Two short, two long
27 One short, one long, two short
28 Two short, one long, one short
29 Three short, one long
30 Four short
3 — ASSIGNMENT OF CALLS TO OCCUPIED 'STATIONS
The first fourteen of these signals consisting of only three elements or less should
be assigned to the busier and more important stations. The ones consisting largely
of short rings and especially those beginning with a short ring, should be given to the
nearby stations. The remaining sixteen rings consisting of four elements each are
arranged approximately in the order in which they will transmit best over long lines in
poor condition. Of course, nearby stations may be given a signal from near the end
of this list, either when they have little business or when they have considerable
business but there are no short calls available.
4 — ASSIGNMENT OF CALLS TO UNOCCUPIED STATIONS
A number of stations will often be located on forest lines where it is not antici-
pated that any calls will be put in. The lookout telephone sets, for instance, mounted
on posts are usually cut off from the line by a switch and only used for calling other
stations. Such telephones, however, should be assigned a four-element, or if necessary
a five-element, call, so that if at any time they are used for an extended period the
various posted lists of calls will show the station signal. It is also advisable to
reserve two or three of the better-transmitting three-element or four-element calls for
the use of emergency stations.
CHAPTER XVI
MAINTENANCE
Section 90— General Principles
Inspection of telephone lines must be made regularly during the fire season, and
special inspection made by the ranger or other officer in charge immediately after a
severe wind, snow, sleet, or electrical storm, and after fires. Rangers and guards
when 011 patrol duty must watch the telephone lines, cut any trees that may have
fallen across them, and make any other necessary repairs. Tests must be made at
a specified hour each morning during the fire season to see that no trouble exists.
Each forest supervisor should establish a regular organization on his reserve for the
proper inspection and maintenance of each Forestry Branch line. When instructed
to do so by the district inspector daily service reports on Forestry Form 318 will
be prepared and submitted for the lines covered by the instructions.
Section 91 — Line
1 — GENERAL REPAIRS
The entire line must be gone over thoroughly at least once a year, preferably
before the beginning of the fire season. Each pole should be inspected; brackets,
insulators, and tie wires which are broken should be properly replaced; and all foliage
and interfering timber cleared away. Poles should be examined for butt-rot and for
twist. In the latter case it should- be determined whether the pole has twisted to an
extent to permit the line or tie to touch it. Loose guys or braces should be tightened
and all loose or badly corroded joints renewed.
Line troubles will generally be traced to one or more of the causes given below.
(Telephone Circular, April, 1916, United States Forest Service, District No. 5.)
(1) Broken line wire.
(2) Line wire resting on the ground.
(3) Leaks through slight grounds by the line wire making contacts with foliage,
trees, poles, or other similar objects*.
(4) Cross-talk and cross-ringing by contacts with other lines.
(5) Short circuits and cross-contacts with other lines at switching stations.
(6) Poor grounds.
(7) Bad splices, and loose or corroded contacts at fuse and protector.
(8) Circuits too long for the size of wire employed.
(9) Decay of poles through butt-rot.
2 — TEST-STATIONS
On lines more than 15 miles long one or more test-stations should be established.
These should be so arranged that the line may be looped into the house or building
where the telephone is and through two switches placed near the latter. The instru-
ments should be connected to these switches in a way to make it possible to cut off
either end of the line, while the instrument remains1 on the end desired, and yet
bridge to the line when both switches are closed. In this way the line may be cut
by the switches for testing in either direction and line trouble may be more readily
located between certain definite points.
142
MAINTENANCE
143
By opening switch A, Fig. 92, the telephone is connected to one side of the line
only. By closing switch A and opening switch B the telephone is connected to the
other end of the line. By closing both switches A and B the line is in normal con-
dition. Care should be taken after making tests' that both of the switches are left
closed, otherwise no calls can be sent through.
If desired, provision can be made at any point on the line for testing it in either
direction with a portable telephone. In snch cases the line wire should be cut and
dead-ended from both directions on the same pole with a two-piece transposition
insulator, or two brackets.
« s.
1!
00
s/-
Fig. 92 Method of installing test-station indoors
The ends should be left long enough after dead-ending to be joined together with
a test-connector, so as to complete the circuit, or a pair of switches may be installed
as shown in Fig. 93 and joined to the line with insulated wire. Such stations, how-
ever, should not be placed where they are likely to be tampered with. In most cases
it would be preferable to house the switches in a suitable box kept locked with a
Forestry Branch standard padlock.
The voltmeter test-stations might be us'ed at logical switching centres. The dis-
trict inspector should be consulted, however, before equipment of this kind is pur-
chased.
3 — DISCONNECTING BRANCH LINES IN WINTER
Since any trouble occurring on branch lines to a lookout point or ranger station
may injure the entire telephone system, such lines should be disconnected from the
main line whenever they will be out of use for a considerable period, especially during
the winter.
The disconnection from the main line may be m>ade by a suitable p>le-switch,
properly mounted, as shown in Fig. 40. A Fahnestock test-clamp may also be used
for this purpose as in Fig. 38.
4 — STUB KEIXFORCEMENT FOR POLES
Poles that have become seriously weakened? by butt-rot near the ground-line
should be replaced, excopt where condilions are such as to warrant reinforcing them
144
METHODS OF OOMMUNIOATION FOR FOREST PROTECTION
tu
stuff enafs ive// sp/iced
white
/nsu/crto/
So/derec/
Staples
Ptece of board with ley el --
surface, nai/ed to its support
To testing instrument"
S/o. /4 B XS Rubber- covered,
braided, Heather-proofec/,
ftr//sfed pair, copper tv/re
Bryant k
switch tfitkjf'X*
blue wood screws.
A/ofe:~ Test stations shou/d not be
instated w/?ere they ore not
necessary.
THEE
Fig. 93 Method of installing test-station on a tree
*by means of a stub of long-lived or treated timber. A stub should ordinarily be used
'where suitable pole timber is not available and to reinforce poles that are sound above
the ground, irrespective of their condition at the ground-line.
The stub or post should be peeled and' shaved and roofed, as shown in Fig. 94.
The sides of the post and of the pole which come in contact should he faced above
;the ground-line to a width of 2 to 4 in., so as to give a greater bearing surface.
The diameter of the stub at the ground-line should be at least as great as would
'be required for a new pole. The weaker the pole to be reinforced the stouter should
'be the stub.
The stub should ordinarily foe set to a depth of 4 ft. and should extend out of
the ground about 5 ft., making the total length from 9 to 10 ft.
Strain on the weakened pole should cause it to bear against the stub. For this
reason stubs in general should be set in line with the line wire. Where there are pre-
MAINTENANCE 145
vailing strong winds from one direction, however, it should 'be set on the side oppo-
site. On curves and at corners a stub should be set on each side of the pole in line
with the line wire. Where any special strain exists, the largest post available should
be used.
Wrappings consisting of No. 12 iron wire should be placed as indicated in Fig.
94. Each wrapping, consisting of eight turns around both pole and stub, should be
made as tight as possible with pliers or other devices and the ends twisted together
with not less than six turns and then 'Stapled to the pole. The wires may be twisted
very tight if >an iron rod about i-in. in diameter or one arm of a pair of cutting pliers
is inserted! between an equal number of turns at a point opposite the line of contact.
Both sets should be twisted at the same time.
Where it is impossible to secure sufficient strength by wrapping the stub and the
pole together by wire, through bolts should be used. The nuts, washers, and bolts
should be of galvanized iron, and the washers about 2J in. square.
No back filling should be done until after the stub is in place. The same method
should be followed as described! under the heading " Setting poles," in Section 55.
5 — REPLACEMENTS WITH TREATED STUBS
In some of the older Forestry Branch lines many poles were used which through
improper preparation or use of non-durable species have decayed very rapidly and
must be replaced. In making such replacements where the use of more durable poles
is specified by the district inspector, some cases will arise wherein treated stubs can
be employed! to great advantage. It will be apparent that the treatment and trans-
portation of stubs is a much less expensive operation than the handling of full-
length poles, and where durable pole timber for making replacements is not available,
the use of treated stubs should be carefully considered. Stubs of a durable, species
have similar advantages.
In making such replacements, however, careful consideration must be given to
the condition of the portion of the old pole remaining above ground. Unless this
portion of the pole is in first-class condition and gives promise of. lasting as long as
the reinforcing stub employed, this method of making pole replacements should not
*be adopted.
6 — RESETTING OF SHORTENED POLES
The standard specifications for non-durable poles call for a 25-ft. length. Where
such poles have decayed and it is desired to replace with durable poles, this object may
frequently be attained economically by cutting off the decayed portion of the old poles,
treating the sound portion remaining, and resetting the same in the line. This, of
course, reduces the height of the lead and cannot be employed1 where such reduction is
for any reason undesirable, but in most cases the reduction will still leave a 20-ft. pole
and this will often be sufficient. Projects involving the treatment and resetting of
shortened poles must always be reported to the district inspector and approved by him
before being undertaken.
Section 92 — Apparatus
1 — GENERAL REPAIRS
All telephone apparatus at stations and elsewhere on the line should be carefully
inspected for loose connections or other defects. The inspector should call up the
terminal or intermediate stations from each instrument and note particularly how the
generator of the instrument rings its own bell and how the bell rings at the station
called.
The called station should ring back in order to test the bell at the calling station.
In making tests it should not be taken for granted that something is wrong if an
79211— 10
146
METHO'DS OF COMMUNICATION FOR FOREST PROTECTION
answer is not immediately obtained. If unable to get the station after several attempts,
call another station and. try to get a test with it.
While the standard instruments and apparatus of the Forestry Branch are among
the best made, and liability to trouble with their mechanism has been reduced to a
minimum, nevertheless the conditions of use of forest lines are such that certain
defects will develop from time to time and frequent, careful inspections are necessary
to maintain the equipment at maximum efficiency.
Seat/on A A
8 Wraps o~F* /2 Wire
Fig. 94 Stub reinforcement of poles
The following list of faults taken from the circular of instructions issued by
District No. 5 of the United States Forest iService will be of assistance to those who
are not experienced in making thorough inspections of telephone apparatus: —
All parts of receiver should be intact.
Receiver cord should be intact.
All nuts on receiver should be tight.
MAINTENANCE 147
Receiver cap should be fairly tight.
Bent, dented, or rusted diaphragm of receiver should be replaced.
Dirt on or under diaphragm should be removed.
All wiring inside of instrument should be in good condition.
Generator should ring the bell clearly with switch open.
Generator crank should not bind when turned. When binding comes on gradually
some operators do not know the difference. It is caused by grounds or lack of oil.
Short circuits may cause either gradual or sudden binding of the generator.
Contacts of the switch-hook should be clean.
Generator should be fastened in the instrument securely.
Contact points of the generator (left side) should make good connection.
All screws inside the instrument should be tight.
Adjusting nuts on bell 'should be tight.
Resistance of all ringer coils should be the same.
Nuts on protector should be tight.
Protector blocks should 'be free from soot, smoke, or dust.
Protector blocks should be metal, not carbon.
Protector should be connected as shown in Fig. 45.
Protector should be screwed (not nailed) to wall.
!Micas should not be cracked or otherwise injured.
Nuts on cut-off switch should be tight (if switches are installed).
Blades of cut-off switch should make good contact with springs.
Instrument should be screwed (not nailed) to wall.
Ground rod should be standard.
Ground wire should be soldered k> ground rod.
Ground rod should be driven into ground within 8 in. of its full length.
Line wires and inside wires should be soldered where they connect with each
other.
Splices in insulated wire should be taped.
Entering wires should run through circular loom or porcelain tubes.
All wiring outside should be insulated properly from buildings by being attached
to knobs or insulators.
Insulation should be good on all inside wires.
All battery connections should be tight.
Transmitter arm should be screwed tightly to box.
Transmitter arm should be tight enough to hold it in proper position.
All nuts and screws on transmitter should be tight.
Metal parts of battery should not touch each other.
Are batteries good? Should be three.
The following instructions may be of value to officers who have occasion to test
instruments and hunt for faults : —
(1) Test the batteries with the battery gauge to determine whether or not they
are exhausted.
(2) Clean all battery connections, post terminals, and ends of all connecting
wires that have become corroded. See to it that all battery terminals, nuts, or screws
on the binding-posts are thoroughly tightened.
(3) Follow up the wires from the battery to the instrument. Repair them where
damaged, and staple if they have become loosened.
(4) Tighten all loose connections1 in the telephone instrument.
(5) See to it that the switch-hooks work freely. Note carefully that a good con-
nection between the contact springs of the receiver hook is made when the receiver
is off the hook and the lever is up, and that the contact is broken when the receiver
79211— 10£
148
METHO'DS OF COMMUNICATION FOR FOREST PROTECTION
is on the hook and lever is down. The operation of the switch-hook is sometimes
subject to slight imperfections on account of improper working of the switch-arm.
This is caused by the lifter spring of the switch-arm losing its tension.
5/mp/e Method of Testing
ffece/ver
Batteries
Connect w/re A to one 3/c/e ofco//
fo be tested and touch w/re & to
ot/ier s/c/e. 'fc/tc/c /^ Sieord ' co//
t's O /<
Fig. 95 Receiver >.test
•^
(6) Inspect the ringer to determine whether or not the tapper and gongs are in
proper adjustment. If not, proceed to adjust them as directed in Section 92. Also
refer to Fig. 96.
(7) Gently tap the transmitter to foe sure the carbon granules are not packed.
(8) The Receiver. The efficiency of the speaking service gradually declining is
the most common fault in receivers. This is due to the accumulation of filings, dirt,
and rust on the pole pieces which restricts the vibration of the diaphragm. To remedy
this difficulty remove the cap, take off the diaphragm with the large end of the
receiver down, and gently jar the receiver to remove the filings, etc. The pole piece
should be carefully wiped with a clean rag to remove dust, and rust if it is corroded.
(9) Speaking service is also often restricted on account of the diaphragm touch-
ing the pole piece. This is generally caused by the magnet shifting, or by the
diaphragm having become weakened by the continual pull of the magnet against it.
Buckled or bent diaphragms are frequently found. This trouble is generally caused
by inquisitive or careless persons tampering with the diaphragm. When this fault
MAINTENANCE 149
is found, temporary relief may be provided by inverting the diaphragm when it is
replaced. A new one should always be provided as soon as possible.
(10) The receiver casings are sometimes damaged by expansion and contraction
due to changes1 of temperature. This sometimes causes receiver trouble, which can
be remedied only by supplying new casings.
(11) Inspecting the receiver cord. If the ends are frayed a short circuit often
results. If the receiver cord is suspected of being broken it should be removed and
tested. It is often very difficult to detect a break in the receiver cord, since it appears
intact at one movement, while at the next its continuity is broken. If such difficulty
is suspected a new one should be provided.
(12) Receiver coils are occasionally fused or burned by electrical currents dur-
ing lightning storms. When this happens new receivers must be provided.
(13) The wires of a telephone instrument frequently become damaged, and
break. When this1 occurs it is sometimes possible to detect the trouble only by testing
with a buzzer or by the " receiver test." If the wires are intact the buzzer will hum
when the wires of the buzzer apparatus are attached to the respective ends of the
suspected wire. If the receiver test is applied a click will be heard when the end
of the wires leading from the receiver apparatus are applied to the respective ends
of the suspected wire.
(14) Induction coils. Fortunately, faults in induction coils seldom occur. They
are, however, not immune from damage and sometimes are burned by electrical cur-
rents during lightning storms, or if the line wire leading to the instrument comes
in contact with transmission lines carrying high-voltage currents. When damaged,
a new one must be supplied.
A word of caution, however, must be spoken in regard to the tampering with
telephone apparatus of those who are entirely inexperienced and ignorant of the
mechanism of the equipment. Hasty action may cause much more serious difficulty
than that which it is undertaken to correct. Repairs should be undertaken cautiously.
If the apparatus does not work well do not meddle with it until you have located the
seat of the trouble and know just what to do to correct it. If the fault cannot be
found, the instrument should be removed and placed in the hands of an expert for
repairs.
In most cases it is advisable to send the instrument to the nearest office of the
manufacturer. To enable this to be done without interruption of the service, one or
two extra instruments should be kept on every forest reserve and installed temporarily
in the place of any that are undergoing repairs.
2 — BATTERIES
All dry batteries on the line should be replaced at least every twelve months, and
more often if necessary. As far as practicable, all the batteries on a line should be
renewed at the same time, preferably at the beginning of the fire season. A fresh
battery should not be connected to an old one. The inspector should note whether or
not battery connections have become loosened. In putting dry batteries back into a
telephone, the inspector should see that the zinc binding-post on one cell does not
touch the zinc binding-post on an adjacent cell (Fig. 43).
An emergency test to determine whether or not a dry cell is absolutely dfead may
be made by moistening the finger and gripping the zinc binding-pest, and then touch-
ing the tip of the tongue to the carbon binding-post. If a very slight acidulous taste
is noted the cell is not absolutely exhausted, although it may be sufficiently so to be
incapable of giving good transmission. In extreme emergencies exhausted dry cells
can sometimes be temporarily revived to give, sufficient current for sending an
important message over the line 'by driving holes with a nail through the zinc shell
and allowing water to soak in through them.
150 METHO'DS OF COMMUNICATION FOR FOREST PROTECTION
Lightning-protectors should be inspected, and cleaned if necessary, after all electri-
cal storms. No. 60-E protector is cleaned by unscrewing the brass cap from the por-
celain base, removing the metal protector blocks, >and removing from them any soot
or smoke or pits which cause the blocks to touch each other. Both conditions are the
result of lightning jumping across the air gap provided by the mica sheet. In locali-
ties where lightning is particularly bad and the stations are difficult of access two
micas may be inserted between the blocks, thu§ increasing the width of the air gap.
3 — OILING GENERATOR
Once every two or three years one drop of typewriter oil or "3 in 1" should be
placed in each of the places provided with oil cups. Great care should be taken to
see that no oil falls on any of the contacts or rubber bushings of the generator.
4 — ADJUSTMENT OF RINGERS
(The following is from Telephone Circular, April, 1916, United States Forest
Service, District No. 5.)
Ringers not in proper adjustment cause unsatisfactory signalling service. Not
infrequently an extension bell or ringer in a telephone is condemned as worthless,
when in fact it is merely in poor adjustment. When in proper adjustment either
gong, upon one-eighth turn of the generator crank, will transmit a high, clear tone
of the same sound.
All bells connected to the same line should be of the same ringer resistance.
One ringer of different resistance on a line will seriously interfere with signalling.
Resistance of each ringer coil is usually marked 800, 1000, 1250, etc. A ringer having
two coils marked 1000 each has a resistance of 2000 ohms; two coils marked 1250
each indicate a resistance of 2500 ohms1.
The ringers of -a new instrument are often thrown out of adjustment in transit.
When the telephone is installed the ringer should be tested and adjusted if necessary.
(a) Adjustments. — (1) If the ringer is loose on its base, remove the gongs and
tighten the screw which secures the ringer mounting. Replace the gongs and securely
tighten the gong screws.
(2) Before commencing the adjustment, the instrument should occupy the posi-
tion in which it will be operated. If it is connected to a line, disconnect it.
(3) If a coil spring should be found attached to the ringer, remove and discard it.
(4) The base of the clapper rod (the armature) should have very little vertical
play. It should not be tight but should not wobble. It should be adjusted to move
freely on the pivots. In making this operation pay no attention to the sicfe movement
of the armature. To adjust, loosen the lock nut D (Fig. 96), then manipulate the
screw E until the proper adjustment is accomplished. Tighten or loosen to provide
just sufficient play in the armature pivots to be visible.
With the screw-driver hold the screw in place, and with a pair of long-nosed
pliers tighten the lock nut. Care should be taken that the threads are not stripped
in this operation and that the screw does not turn. Only a slight pressure should be
applied to the lock nut.
The gongs should next be so set that the clapper ball strikes but does not rest
against them when thrown from side to side. The space between the clapper ball
and one gong should be about %6 in. when the clapper ball is held against the other
gong. To change the positions of the gongs loosen the clamping screws B only
enough to allow the gongs to be moved by the turning of the eccentric adjusting
screws C until the correct position of the gongs is obtained. Let the clamping
screws remain loose until the stroke of the clapper is adjusted. To make this adjust-
ment turn the screw A to the right to shorten the stroke, and to the left to lengthen
it. Turn the generator handle only enough to cause the clapper to move toward one
MAINTENANCE
151
gong but not to strike back to the other gong at each movement of the handle. The
clapper ball should strike the gongs and rebound just enough to clear the gong. It
should lie as close as possible without touching the gong.
Sometimes the clapper ball tends to rest heavily to one side. If possible" the
difficulty should be overcome by moving the gongs or by changing the length of the
stroke of the clapper. If the attempt is not successful, bend the clapper rod until the
required space is obtained. Then move the gongs to their proper relative positions.
Fig. 96 Ringer of No. 127-F, extension bell, and Nos. 1317-P, 1317-S,
300-N and 1336-J telephones
(Z>) Testing. — When the gongs and clapper ball appear to rest in their propor posi-
tions, test the adjustment by turning the handle of the generator - until the clapper
ball strikes one gong without striking back to the other. If the tones are not satis-
factory, continue the adjustment until a clear ring of the same tone is emitted by
each gong, and at the same time the stated spaces between clapper ball and gongs must
be maintained. The clamping screws B should be tightened when the adjustment
is complete.
Adjustment of ringers in extension bells differs only in method of testing. The
test is made by slowly and slightly tipping the ringer from side to side. It should
not be jarred.
The 292-U loud-ringing extension bell can be more successfully adjusted when
it is connected to a line. This allows the adjustment to be tested by signalling to it
from some distant telephone. The bell should be installed in a true vertical position;
with the clapper pointed either upward or downward.
The coil to which the clapper is fastened should move freely between the upper
and lower pivot screws, but not loosely. This adjustment is made by manipulating
the screws on either side of the armature. The space between the clapper ball and
gong should be about £ in. when the clapper ball is held against the other gong. The
gongs are adjusted by loosening one at a time the square-headed screws on the face
of the gong, turnrng the gongs to the proper position and then tightening this screw
152 METHODS OF COMMUNICATION FOR FOREST PROTECTION
before each test. The distance between the clapper ball and the gong after rebound
of the clapper ball should be approximately KG in. If in proper adjustment, each gong
when struck by the clapper should emit a clear, ringing sound.
5 — PORTABLE TELEPHONES
The two standard portable instruments, the 1375-A and the 1004- A, are so con-
structed that they are very unlikely to give trouble unless tampered with. Owing
to the small size of the battery employed in both these telephones it is necessary to
make more frequent renewals than in the permanent sets. No adjustments are
required in the 1375-A set, but in order to get the best results from the buzzer of the
1004-A set it is sometimes necessary to alter the .spark gap. This should not be
attempted in the field, and any instruments not working satisfactorily should be
returned to the district inspector for repairs.
The 1004- A hand set and the hand set of the 1375- A 'instrument being of rather
thin sheet aluminium are very liable to serious injury through denting. Such dents
may cause short circuits which interfere with the successful use of the instruments.
When these occur they may often be removed by pressing out from the inside, using
a smooth piece of hardwood with a rounded surface.
Section 93— " Trouble "
1 — BROKEN CONNECTIONS AND OPEN COILS
In the instruments that the Forestry Branch has adopted as standard the chances
for trouble have been reduced to a minimum. Lightning is the greatest source of
trouble.
The riniger coils, which are constructed of fine insulated wire wrapped around
an iron core, occasionally burn out. When this happens it is necessary to substitute
a new coil. The armature in the generator may also burn out, necessitating replace-
ment. (The armature is the part in the generator that revolves between the per-
manent magnets. This is composed of two windings around an iron base on opposite
sides' of the centre. The generators used on some sets are protected to a certain
extent by means of a " shunt.")
In the receiver the small coil of insulated wire wrapped around the end of the
permanent magnet is sometimes burned out by lightning or heavy outside currents.
The induction coil is sometimes similarly damaged.
The following methods of testing may be used to locate trouble as just described :
Connect one side of a receiver to one pole of the battery. If when the other side of
the receiver is touched to the other pole of the battery no click is heard, the receiver
is open.
By the use of a receiver, if in serviceable condition and the batteries as shown
in Fig. 95, any of the wire coils may be tested.
A test of the generator may be made by disconnecting the instrument and placing
the moistened tips of two fingers over the two screw binding-posts on the end of the
generator. If the latter is in adjustment, current will be felt when the crank is
turned. If no current is felt probably the armature of the generator is open, and a
new armature must be obtained. The hard-rubber bushings sometimes carbonize,
due to oil or grease getting on them, and cause generator trouble.
It is impossible to talk through the transmitter when the induction coil is open,
when the batteries are weak, or when there is a loose connection somewhere in the
instrument, as at one of the connections on the batteries or at the switch-hook.
2 — DETECTION AND KEMEDY
Trouble in any place is likely to affect the entire system. Inexperienced persons
should not be allowed to tamper with telephone instruments. It is usually well to
MAINTENANCE
153
have a spare telephone on each reserve, which can be temporarily installed while a
telephone or the part of it that is out of order is sent to some reliable telephone man
for inspection, repair or readjustment.
In general, telephone trouble may be in connection with (1) signalling or (2)
talking and hearing. The generator furnishes current for signalling or ringing the
Fig. 97 Wiring of No. 1317 telephone set
bells, sending a current over the line to all bells on its way to the ground. The
generated current is intermittent, and jumps to the ground or is greatly weakened
by groundings instead of flowing along the line. The batteries furnish current for
conversation only. It is possible to talk over a wire even when there are slight
grounds through trees or through the line wire touching the ground in dry places,
.but it is not possible to signal.
3 — GUIDE TO CLEARING TROUBLE
Trouble No. I, Bell— Cannot ring up anyone; generator handle turns hard; local bell
does not ring when generator is turned.
Cause. — Protector burned out or dirty. Line wire grounded or wires crossed (ii
metallic) ; improper wiring in set or bushings on generator carbonized.
154 METHODS OF COMMUNICATION FOR FOREST PROTECTION
Remedy. — Wihen testing to discover the cause of this trouble the receiver should
be left on the switch-hook. First disconnect the two wires which enter the telephone
set from the terminals marked " Line 1 " and " Line 2," (see Fig. 97) and screw
down the connections on the wires coming from the ringer. Now turn the generator.
If it turns easily 'and the bell rings well, the trouble is not in the telephone set.
Then connect the line wires to " Line 1 " and " Line 2 " terminals and disconnect
the line wires from the protector, leaving the inside wires to the telephone set
attached to the protector. Now turn the generator handle. If it is difficult to turn,
remove the protector blocks from the protector and try the generator again. If it
turns easily, clean the protector blocks, replace the thrn piece of mica between them, •
and1 put back into the protector. Now test the generator again, <and if it turns prop-
erly connect the line wires to the protector and see if the telephone set works as it
should.
If the generator turns properly when the line wires are disconnected at the pro-
tector, but is difficult to turn when the protector blocks have been cleaned and the
line wire again attached, the trouble is either in the wiring between the protector and
the pole, or out on the line, or in the wiring apparatus at one of the other stations.
Carefully examine the wiring and the line for a place where one of the wire* crosses
another (if the line is metallic) or where the main line or drop wire touches some
ground connection. If in a metallic line the wires are crossed, the generator crank
will turn hard as above described. This is also true of a grounded' line if the wire
becomes crossed with some foreign ground. On a metallic line, if one side of the
wire is touching a ground, a humming noise will be noticeable on the line.
If the generator turns hard even when the line wires are disconnected from the
telephone, look for incorrect wiring or crossed wires in the set or for carbonized
bushings on the generator. When this latter trouble exists the odour of burning
rubber is noticeable when the door of the telephone is opened!.
If every station on the line has the same trouble, call for an inspection of the
protector at each station, or look for trouble along the pole line or in the terminal
arrangements where the line is connected to a switchboard or to another line, and
inquire on that line, if necessary, or disconnect from it temporarily.
Trouble No. 2, Bell — Cannot ring up anyone; generator handle turns easily; local
bell rings when generator is turned.
Cause. — Loose connection or broken wire in set, to protector, line or ground;
line wire broken, or poor ground.
Remedy. — If a metallic line, look for a loose connection at " Line 1 " and " Line
2 " of the telephone set. If a grounded line, look for a loose connection on the main
line at " Line 1 " or on the ground wire which is attached to " Line 2 " in the instru-
ment. Look for a loose connection at the protector or where the inside wiring is
attached to the outside wires. Look for an open fuse. If the trouble is not found
at these points look for a 'broken wire or a poor ground.
Trouble No. 3, Bell — Cannot ring up anyone; generator handle turns easily; local
bell does not ring when generator is turned.
Cause. — Loose connection or broken wire in set, generator armature fails to make
contact with spring.
Remedy. — Look for a loose connection or a broken wire in the telephone set. See
that your ringers are in proper adjustment. It may be that one of the wires to the
generator is disconnected from one of the line wires, or one of the ringer wires may
have become loose or broken.
Trouble No. 4, Bell — Cannot ring other bells or only feebly; local bell rings all right
when generator is turned.
Cause. — Loose connection between telephone and line or ground; poor joints on
line or leaks; poor grounds.
MAINTENANCE 155
Remedy. — Look for a loose connection where line connects with telephone set,
where line connects to protector, or at the ground. It is possible that the trouble may
be due to a poor or corroded splice in the line wire or to contact between the line wire
and trees, poles, or other lines. In the case of grounded lines be sure that the ground
at the telephone you are trying to call is in proper condition. Be sure that your own
ground is in the same condition.
Trouble No. 5, Bell — Local bell does not ring; can ring other bells all right.
Cause. — Broken wire or loose connection to ringer, ringer adjustment bad, or
coils open.
Remedy. — Look for a broken wire or loose connection in the wires coming from
the ringer. If the connection and wire are all right, see that the ringer is properly
adjusted. Make a test on your ringer coils to see that they have not been burned out
as previously described. If only a feeble ring is received from other stations or when
ringing your own bell, the trouble is most likely with the adjustment of the ringer
which has probably been tampered with. Occasionally the ringer magnet becomes
weakened and causes a similar result.
Trouble No. 6, Bell — Can ring other bells only feebly; receives a strong ring from
other stations.
Cause. — Weak magnets or bad connection in generator.
Remedy. — This may result from weakness of the permanent magnets of the
generator, but it is more likely due to a poor connection between the generator and the
line. If not in the wiring there may be faulty connection between the shaft of the
armature and the spring against which it presses when the generator is turned. This
contact must not be oiled. Oil at this point offers a high resistance that greatly
reduces the ringing current.
Trouble No. 7, Bell — Rings frequently with no apparent cause.
Cause. — Intermittent cross with foreign lines.
Remedy. — This trouble can only arise where the line is on the same poles as a
foreign telephone or telegraph line. If it makes a contact with such other wires by
swinging across them the bells will be rung but there will be no response.
Trouble No. 8, Transmitter — Can hear others all right but others cannot hear you.
Cause. — Loose connection or broken wire in primary circuit; carbon packed;
battery weak; speaker standing too far from transmitter.
Remedy. — Look for a loose connection or broken wire coming from the trans-
mitter battery, induction coil, or switch-hook. See if the connections to the induction
coil are all right. If this examination does not show anything wrong, thump the
underside of the transmitter lightly with the hand, as the carbon granules in the
transmitter may have become packed. If this fails to improve matters the trouble
may be due to an exhausted battery.
If speech transmitted is indistinct with a scratching or grating noise, look for a
loose connection at the battery, induction coil, or in the fine wire connecting the
carbon of transmitter to the cord terminal.
Trouble No. 9, Receiver — Cannot hear others distinctly; others hear you all right.
Cause. — Loose connection on receiver circuit; diaphragm bent or dirty.
Remedy. — Look for a loose connection or broken wire coming from the receiver,
switch-hook, or induction coil. Unscrew the ear-piece from the receiver and brush out
the inside and wipe off the diaphragm. Also brush off any particles that may have
collected on the magnets underneath the diaphragm. If the diaphragm is bent in,
turn it OTer.and replace the ear-piece. Screw this on firmly, but not very tightly.
156 METHODS OF COMMUNICATION FOR FOREST PROTECTION
If this does not reveal the cause of trouble, unfasten the receiver cord from the
terminals in the telephone set and, while holding the receiver to the ear, touch the
two terminals of the receiver cord to the terminals of one of the dry batteries. If you
can hear a click when the cord is connected thus, the receiver is all right and there
must be some fault in the wiring. If you do not hear a click, it is probable that the
receiver winding or the cord is broken.
If you cannot hear at all, the fault is due to a broken wire in receiver or cord.
Trouble No. 10, Neither you nor others can hear distinctly.
Cause. — -Poor joints or connections, batteries or grounds.
Remedy. — The trouble is probably due to some loose connection or poor or corroded
joint in the wiring at the telephone station or out on the line, exhausted batteries or
poor grounds or a loose lightning-rod touching the line.
Trouble No. II, The stations at the terminals of the lines have increasing difficulty
in ringing or hearing each other plainly.
Cause. — Too many stations on line; too long a line for size of wire used; ground
rods in too dry soil; corroded splices; poor joints; excessive line leakage through
contact with trees, poles, or foliage.
Remedy. — Fix up the entire line. If this improves the talking but not the ring-
ing, see that all the telephones on the line have 2,500-ohm ringers. See that the
generator crank-shaft comes back into place after calling a station on the line. If
this does not make the ringing satisfactory, cut off some of the stations or divide
the line into sections, or rebuild the main line, using heavier wire. In extreme cases
it may be necessary to build' a copper, metallic circuit. The fault may be due to
similar conditions or poor maintenance on a foreign telephone line or switchboard
to which the Forestry Branch line is connected.
4 — CROSS-TALK
Cross-talk occurs when two grounded lines are strung on the same poles. This
interference with conversation is reduced as far as possible on a grounded line by
good grounds at all subscribers' stations. Separate ground rods should be used for
separate lines. If it is desired' to eliminate cross-talk, the circuit must be made
metallic and the standard method of transposition followed. By making one of the
two lines metallic, cross-talk is eliminated on the metallic line but may still cause
trouble on the grounded line. Cross-talk will not generally arise unless the Forestry
Branch line parallels a second grounded or metallic line, closer than 30 ft., for a
distance of more than a quarter of a mile.
5 — STATIC ELECTRICITY
A great deal of inconvenience may be caused by static electricity. There may be
no trouble in the morning, but toward noon a frying noise is apparent and! in the
evening it is impossible to carry on a conversation. Trouble from static electricity
is usually greater at high altitudes than at low.
One method of removing static electricity from a linens by the use of a lavite
coil with a resistance of 48,000 ohms. This coil should be installed along the lino
at intervals of from 3 to 10 miles, and attached to a grounded line as shown in Fig. 51.
In a metallic line two coils should be attached, one to each wire. The same ground
may be used for both coils. The coil should be inclosed in a small weather-proof
box.
Another method of draining static electricity is by the installation of vacuum
lightning-protectors. These protectors should be installed in the same manner as
the lavite coil, except that the fuse may be omitted.
It is sometimes necessary to make a study of static conditions, as the distance
between coils is not the same in all cases. Before doing so the district inspector
should be asked for definite instructions.
CHAPTER XVII
TELEPHONE "DON'TS"
Section 94— Construction
Don't build telephone lines without a systematic plan based on a careful study
of all the existing conditions and probable developments.
Don't fail to get a right of way over private lands before starting construction;
also a permit to cross all railways and power-transmission lines.
Don't start to build a telephone line until you have all your supplies on the
ground.
Don't use unseasoned poles. Prepare your poles a year in advance of construc-
tion, if possible.
Don't use short-lived poles of such species as poplar, spruce, or lodgepole pine,
unless treated with a preservative, except where such use is specifically authorized
by the Director.
Don't put creosote or other preservative on green poles nor on wet or frozen
poles.
Don't use unpeeled poles or poles without a roof ridge.
Don't use iron wire smaller than No. 9 B.W.G. for tree lines in any case or for
pole lines without special authority.
Don't try new methods of constructing tree lines until you have had experience
both in building and maintaining lines in the way specified in this manual. These
methods are the result of years of experience by hundreds of men, and the chances
are your new scheme was tried and abandoned years ago.
Don't cross roads or trails with lines if you can possibly avoid it.
Don't put telephone wires on the same poles with electric-light or power-trans-
mission lines.
Doii't put grounded lines on poles with any other wires whatever.
Don't run a tree line nor a grounded line near a high-tension transmission line.
Don't use sleeve connectors to make splices on iron wire and don't make splices
any other way on copper wire.
Don't string wire in a lightning storm.
Don't try to pay out wire from a coil without a reel.
Don't leave the cross-bar, used as a hand-hold in pulling wire, attached to the
wire after the coil is pulled out. \
Don't drag copper wire along the ground as you do iron wire nor throw the coils
from cars or wagons.
Don't let any kind of wire lie out on the ground where horses or wagons may
run over it.
Don't nick the line wire with your pliers nor burn it in making ties.
Don't guy to bushes or saplings or driven stakes. Use standard methods.
Don't attach any guy to the ground* at a point nearer than 8 ft. from the base
of the pole and preferably at a distance from the base of the pole equal to the distance
from the ground to the lower bracket.
Don't put unguarded guy wires on a public road or street.
Don't put brackets on poles or curves so that the line wire pulls away from the
pole.
Don't put split insulators on trees on curves so that the line wire pulls toward
the tree. Always with split insulators have the pull away from the tree or other
support.
Don't use brackets and glass insulators on trees.
157
158 METHODS OF COMMUNICATION FOR FOREST PROTECTION
Don't use tight ties on the occasional poles used in tree lines to cross meadows
or other openings. Consider them as trees.
Don't pull a tree line tight. Leave at least 4 ft. of slack, more where possible.
Don't use Buffalo grips on tree lines. Pull all slack by hand.
Section 95 — Installation
Don't have any more inside wiring than is unavoidable. Determine the best
permanent location for the telephone and bring the wires through the wall as near
this point as possible.
Don't install telephones or extension bells of different resistance ringer coils on
the same line. All coils must fce alike.
Don't put the standard indoor telephone set in a damp place nor where it may
be exposed to the weather. The metal-covered set has been adopted for such places.
Don't under any circumstances connect up an instrument without a protector.
The first lightning storm may ruin it.
Don't fail to fasten the tension cords on both ends of the receiver cord1 when
attaching the latter to receiver and interior binding-posts. This prevents strain
on receiver-cord conductors and saves breakage.
Don't attach any of the equipment with nails. Use only wood screws of the
proper size and type.
Don't expect a slipshod job of wiring to work satisfactorily. A good workman
takes pride in the appearance of his work as well as in its working qualities. A
poor-looking installation is practically always a poor-working one also.
Don't put two wires under one staple. Use insulated staples only and1 fasten
each wire separately.
Don't run wires near metal pipes or drains.
Don't leave exposed joints in the wiring. SoldeV and tape properly.
Don't run unprotected wires through the chinking or between the logs of a log-
house. Bore holes through a log and put in porcelain tubes.
Don't £hink you can make a good ground on any old iron rod or piece of wire or
junk that may come handy. Any iron not galvanized will rust and this rust is
practically a non-conductor. Use only galvanized iron, or copper, with as large a
surface as possible, making a moist contact with the earth.
Don't expect to get a good ground except in permanently moist earth. This
means earth, not rock, and it means earth that neither dries out nor freezes.
Section 96 — Operation
Don't try to ring with the receiver off the hook.
Don't ring in on a line until you have both " listened in " and also inquired
if the line is busy. The line may be in use even though no one is talking when
you " listen in ".
Don't think because the station called fails to answer on the first ring that the
line is broken or nobody at home. Have some nearer station try to raise the person
wanted. Learn the habits of your man. He may be out after his horse or getting
in a supply of water for the day. Be persistent.
Don't forget to ring off after talking. There may be others waiting for you to
finish your conversation.
Don't be too ready to blame operating trouble on the instruments. Nine times
out of ten trouble is due to the condition of the line, the ground, or the installation.
Also nine times out of ten, if the instrument does get out of order, the fault lies
with the person using it and is due to carelessness or ignorance.
Don't experiment with the interior mechanism of the instruments. Learn all
about the telephone and you won't have to experiment.
TELEPHONE " DONT'S " 159
m
Don't stand too far from the transmitter when talking. Talk from two to six
inches only from the mouthpiece and directly into it.
Don't shout into the transmitter. Enunciate distinctly arid directly into the
transmitter. Clear enunciation, properly placed, transmits better than loud tones.
Don't hang the receiver with the diaphragm up. This simply serves to- collect
dust. If the switch-hook is too big to hold the base of the receiver make it smaller
by bending the arms together.
Don't tap on the diaphragm of either transmitter or receiver with a pencil or
other article. If the receiver diaphragm is bent, get a new one. It can be removed
by unscrewing the hard-rubber cap of the receiver.
Don't drop the receiver. The shell is hard rubber and brittle.
Don't leave the receiver off the hook for long periods. This exhausts the local
battery. 'With portable outfits having push-button on hand sets, be sure the push-
button is not depressed when you pack the set for transportation.
Don't open the door of the telephone out of curiosity and then forget to fasten
it again.
Don't allot signals to stations promiscuously. It saves time and patience to give
the stations most frequently called the shortest signals.
Don't fail to post a copy of the " Operating Rules and Station Calls " at every
station, close beside the instrument. This includes outdoor stations, also.
Don't expect a line through timber to maintain itself. If you must have a line
with the minimum of maintenance, cut a 100-f€ right of way and1 build a standard
pole line.
Section 97 — Maintenance
Don't try to maintain lines without systematic tests. Test daily to all stations
and correct immediately all breaks or other line or station troubles.
Don't fail to make at least one general overhauling a year; two are better.
Don't let fallen trees accumulate across tree lines. Keep them cut out and
make it the duty of every forest officer alwa"ys to clear the line of trees encountered
on patrol.
Don't fail to inspect and clean lightning-protectors after every electric storm.
Don't put paper between the protector blocks. Keep a few extra micas on hand
for repairs at each station. Also a fuse or two.
Don't fail to put in new batteries at least annually; more often if necessary.
With portables using small flash-light batteries, get fresh ones every two months.
Don't replace batteries one cell at a time. Put in an entirely new set.
Don't buy batteries locally unless you can get standard telephone batteries and
can test them. Motor ignition batteries are the usual kind at local supply houses and
are not so good for telephones as the special brands. Get your batteries regularly
from telephone dealers.
Don't forget that dust is prevalent in many forest cabins and that its accumula-
tion on the parts of the instrument and its accessories is injurious. Keep them clean.
Don't expect binding-posts and other non-soldered connections to remain tight
and clean indefinitely. They all have a tendency to work loo'se, and often corrode, and
should be fixed up occasionally.
Don't try to make repairs to delicate parts of the instrument unless you are
an expert. Send it back to the factory and substitute a spare telephone in the mean-
time.
Don't oil the hinges of the box.
Don't oil any part of a telephone unless you have the proper equipment for doing
so and know where to put the oil. Improper oiling will ruin the generator.
Don't climb old poles without testing to make sure they are not rotten at the butt.
Don't hesitate to pour water around your ground rod frequently.
PART III
FOREST PROTECTION HELIOGRAPHS AND OTHER SIGNALLING
APPARATUS
CHAPTER XVIII
HELIOGRAPH
Section 98— The Instrument
The heliograph is a visual signalling device consisting essentially of a plane
mirror and certain auxiliary equipment by which flashes of light reflected from the
mirror may be directed toward any given point. For purposes of communication these
flashes are generally made to form the symbols of the telegraphic code, a short flash
representing a dot; a long flash, a dash.
The heliograph is almost exclusively used as a daylight signalling device only
and requires full sunlight for its successful operation. Within certain limits, which
will be hereinafter discussed, the heliograph is, next to the telephone, the most useful
communication device that is at present available for forest-protection purposes.
Heliographs are of two main types: — (a) Moving flash; (Z>) Fixed flash.
The first type is represented by the British Army heliograph. The second type
is^ represented by the United States Army and the United States Forest Service
heliographs.
Section 99 — Use in Forest Protection
Although the heliograph has been used by the army for the purposes of com-
munication for a great many years, its use in forest protection is a recent develop-
ment. So far as is known, this instrument was first employed in forest protection for
communication between lookout stations under the direction of the author on the
Kaniksu National Forest in Idaho in 1909. This successful demonstration of its
utility has been followed by a slow but widespread adoption of the instrument for
certain restricted uses on a large number of the National Forests of the United States,
and at least one instance of its use in Eastern Canada has been noted. The recent
invention by Supervisor D. P. Godwin, of the United States Forest Service, of an
improved form of heliograph for forest protection purposes, promises to enlarge greatly
the sphere of usefulness of this instrument. While realizing fully the limitations of
the heliograph, especially for use in the East or in a flat country, the author believes
that its capabilities for enabling the members of a specialized forest-protection staff
to maintain intercommunication are very far from being fully utilized or even
appreciated.
Heliograph stations as employed in forest protection are of three classes : perman-
ent, semi-permanent, and temporary.
Permanent stations include mountain lookout stations or other fixed points in
the forest improvement system where signals may be sent or received with a high
degree of dependability during all or part of the fire season. Lookout stations are,
from their location and use, heliograph stations of the very first importance, since
they not only have a wide range of country constantly under observation but may
themselves be picked up with little difficulty from most of the area within their range.
Semi-permanent stations are those established at or near temporary camps such
as fire, survey, or construction camps or near ranger stations that are not connected
to the telephone system. Stations of this class will likely be occupied for signalling
160
THE HELIOGRAPH 161
purposes during only a limited portion of the day. "While their dependability for
sending purposes may be high, they are not adapted for receiving messages except
during the periods when they are actually occupied. Such periods may be regular or
not, according to the facilities and organization in each case.
Temporary stations are those established by moving patrol or other moving units
of the forest force merely for the purpose of communicating with some other station
in the forest. As a rule they will be used for sending messages only and will have
little or no value as receiving stations, since they will seldom be occupied regularly
but will generally be established only as the moving unit finds it necessary to com-
municate with headquarters or some other station.
It is obvious that in the first two cases the element of easy portability is of much
less importance than in the third. At the most, a heliograph outfit, even of the largest
size, is quite easily carried by one man, so that where it is simply a question of setting
up an instrument in a suitable location at a permanent or semi-permanent station,
any of the usual types may be employed. No special heliograph equipment is there-
fore needed for lookout or headquarters use but, as rigidity is an element of some
importance and as range is governed by the size of the mirror, one of the heavier
models should be selected and the size determined by the ranges over which it is desired
to work.
When,however, the heliograph is to form a part of the outfit carried by a foot
or horse patrolman the question of size and weight becomes extremely important.
Such patrolmen are usually loaded to their carrying capacity with tools and supplies
requisite for their work, and every item of their equipment must be reduced to the
lowest practicable weight. The ordinary military heliographs even of the smaller
sizes are too heavy and too bulky to be made a part of the outfit of either a foot patrol-
man or horse patrolman, though they might be used by canoe patrol where few portages
are necessary, and may be easily carried on any wheeled vehicle used in forest protec-
tion except a motor-cycle. This difficulty would seem to be successfully overcome by
the new Godwin heliograph described herein.
In general the heliograph will find useful application to forest protection inter-
communication in the following ways: —
(1) Before the construction of the telephone system, to furnish communication
facilities to all parts of the forest.
(2) As a substitute for an emergency telephone line, operating from temporary
camps to lookout or other permanent stations on the main telephone system.
(3) As an emergency equipment at all permanent lookout stations to ensure against
isolation of the station in the case of a break in the telephone line.
(4) As a cheap substitute for a telephone on secondary lookout points occupied
during a limited portion of the fire season or during an unusually dry season only.
(5) As a cheap substitute for a telephone on lookout peaks which it has not yet
been decided are entirely suited for permanent occupation.
Section 100 — Range and Speed
The range over which the heliograph can be operated depends on the size and per-
fection of the mirror, the brightness of the sun, the clearness of the atmosphere, and,
to a much smaller degree, upon the angle at which the light is reflected from the mirror
and the background against which the signals are seen. While the normal working
range of the 4|-in. square or 5-in. round mirror heliograph is about 40 miles, either may
be read by the naked eye under ordinary conditions at 50 miles without difficulty, and
up to 90 miles with a glass. In the clear atmosphere of the West, ranges of 100 miles
have been accomplished. For longer ranges a larger mirror is required. With an 8-in.
square mirror signalling has been carried on in Arizona between stations 186 miles
apart. Practically, signals may be exchanged between any two points which are inter-
visible, regardless of their distance apart. Intervisibility will depend on their distance
79211—11
162
METHODS OF COMMUNICATION FOR FOREST PROTECTION
apart, their height, and the height of the intervening ground. The curvature of the
earth is the important controlling factor, although signals may be exchanged between
points when the right line joining them passes through the intervening ground. On
account of refraction of the beam of light its trajectory is an upward curve that passes
above the right line joining the two points. (For a discussion of the mathematical de-
termination of the intervisibility of any two points, see "Manual of Visual Signal-
ling," United States Signal Corps, pp. 83-88.)
In actual practice, however, it is .seldom necessary to operate over ranges of
greater than 30 to 40 miles and at these distances any of the types of heliograph em-
ployed can be depended upon to give satisfactory service.
Speed is entirely dependent upon the skill of the operators. It is comparatively
easy to attain the ability to send and receive at a slow rate but speed comes only with
training and practice. Twelve words per minute may be .sent by skilled operators. In
forest-protection work, four to six words per minute may generally be depended upon.
Section 101 — Types of Heliograph
Although all heliographs operate on the same general principles, there are
important differences in the manner in which they cause the revelation and obscura-
tion of the flash. Among those which operate by the moving flash method the type
employed in the British Army is most commonly seen in Canada.
Fig.
HELIOGRAPH WITH SIGHTING VANE.
British Army type of heliograph, one-mirror
1 — BRITISH ARMY TYPE
The British Army heliograph consists essentially of a circular mirror mounted
on a horizontal axis on which it is free to move. By means of an attached linger
key, this mirror may be tipped so as to throw its flash on the distant station when
properly adjusted. Between each revelation of the flash, the light is thrown below
THE HELIOGRAPH
163
or on the near side of the distant station and is not visible therefrom. This mirror
is mounted directly over the head of the tripod on which the instrument is sup-
ported when in use, and various parts required for its proper alignment, adjustment,
and operation are provided. For use when the sun is behind the operator, a second
mirror is employed. The details of this instrument may be seen in Figs. 98 and 99,
wherein it is shown as employed with one and with two mirrors.
HELIOGRAPH WITH DUPLEX MIRROR
Fig. 99 British Army type of heliograph, two
List of Parts, Figs. 98 and 99: A, signalling mirror in metal frame; B, U arms for ditto; C,
tangent box with lid below ; D, tangent screw head ; E, key ; F, key spring ; G, capstan screw,
H, collar ; I, vertical rod in vertical socket ; J, clamping screw for ditto ; K, jointed arm ;
L, clamping screw for ditto ; M, gun clip ; N .clamping screw at end of arm ; O, sighting rod ;
P, sighting vane and mark ; Q, unsilvered spot ; R, German silver ball attached to claw R' ;
S, base plate ; T, key bridge ; U, key bearing ; V, anchoring hook ; W, duplex mirror ; X,
U arms for ditto; Y, butterfly or pivoting screw; Z, tripod.
This type of instrument has the following advantages : —
(1) The sending key is also one of the adjusting screws and the operator can
therefore have both hands on the adjusting screws even while sending.
(2) Only one tripod1 is required and no screen is necessary.
(3) The instrument is manufactured in Canada and more readily procurable
than other types.
(4) Operators skilled in the use of this type may be secured in Canada. Other
types are practically unknown.
There are some disadvantages, however, as compared to other ^ types, several of
which are particularly objectionable for the uses to which the heliograph is mostly
put in forest protection. These will be referred to in considering the advantages
of the several other types .available.
2 — AMERICAN ARMY TYPE
The heliograph adopted by the United States Army Signal Corps,^ which is the
type that has been most extensively employed to date in forest-protection communi-
79211— Hi
164
METHODS OF COMMUNICATION FOR FOREST PROTECTION
cation, operates on the fixed-flash system. In this system the revelation and obscura-
tion of the flash is accomplished not by the motion of the mirror itself but by
means of a separate screen placed between the mirror and the distant station in such
a way as to entirely cut off the light when closed but permit it to pass freely when
opened. Two tripods are required, one to carry the screen and the other the helio-
graph proper. The latter consists of two square plane mirrors, each 4| in. to a side,
and a mirror bar on which these are mounted when in use. As the mirrors when
Fig. 100 American Army type of heliograph, one-mirror
Fig. 101 American Army type of heliograph, two-mirror
A, square mirror ; B, mirror yoke ; C, mirror adjusting screw ; D, unsilvered spot ; E,
tripod ; F, hook for weight ; G, sighting-rod ; H, sighting-rod vane ; I, mirror bar ;
J, screen ; K, screen key ; L, screen spring
once set and aligned do not need to be moved except to adjust them to follow the
motion of the sun, the auxiliary parts are very simple, consisting merely of two
THE HELIOGRAPH 165
tangent screws by which each mirror may be turned on its horizontal and vertical
axes. The details of this type are shown in figs. 100 and 101 as used both with
one mirror and with two.
The screen shown ,'n Fig. 100 is 6& in. square and is operated by a downward
push on the key causing the thin vanes of which it is made to align themselves with
their edges across the path of the beam of light, thus permitting it to pass through
to the distant station. Once the flash is aligned with this type of instrument it
remains fixed! and all movements are confined to the screen by which the dots and
dashes of the code letters are formed.
The advantages of this type of instrument are as follows : —
(1) It is very simple in design with few small parts and none that are subject
to much wear in operation.
(2) The square mirror has a greater area, f<pr practically the same packing space,
than a round mirror of the same diameter.
(3) The movements in operation being confined to the screen, and there being
110 motion to the mirrors, make it much less likely that the latter will ba thereby
thrown out of adjustment.
(4) • Vibration caused by high winds has less effect on the fixed flash as seen
from the distant station than on the moving flash.
(5) There is no possibility of a double revelation of the flash caused' by being
focused too high, as there is with the moving flash.
(6) The "shadow spot" by which the adjustment of the mirror is regulated
reTYio — - continuously on the guide disk and not intermittently as with the moving-
flash type.
3 — FOREST SERVICE TYPE
There has recently been invented by D. P. Godwin of the United States Forest
Service, a type of fixed-flash heliograph which is to a certain degree a compromise
between the British and American types of instruments and which promises to super-
sede the army types for many purposes in forest protection. This type, while retain-
ing the screen and operating by the fixed-flash method, dispenses with the extra tripod
by placing the screen on the tripod carrying the mirror and directly over its head
where the operation of opening and closing the screen will be least likely to cause
serious vibration of the mirror. Further, the construction throughout is designed
to ensure the least practicable weight and bulk and the utmost simplicity of parts.
As it weighs only 4£ pounds complete and has about the bulk of a common post-card
size pocket kodak with tripod, it is a thoroughly practical patrol device and much
superior for this purpose to the other forms. In all essential respects, however, this
instrument is similar to the American Army type. Its general appearance is shown in
Figs. 102 and 103.
Section 102 — Heliographs at Lookout Stations
Extreme light weight is not a feature of much importance for lookout or other
permanent, or even semi-permanent, stations. The large types of army heliographs
weigh from 15 to 20 pounds complete, which is no bar to their successful use at
stations of this character. On the other hand, for lookout service the qualities
required are fairly long range, dependability, and especially rigidity when exposed
to high winds. These are secured to a greater degree with the two army types than
with the Forest 'Service instrument.
Either the British Army form or the American Army form may be used for
station instruments at lookouts. The 4^-inch, square mirror of the latter has almost
the same reflecting area as the 5-in., round mirror and therefore the same effective
range.
In considering the relative merits of the two types of instrument it will be
noted that the British type has the disadvantage that the manipulation of the key :s
liable to throw the mirror out of alignment. This is impossible with the American type
Figr. 102 Forest Service type of heliograph, one-mirror
166
Pig. 103 Forest Service type of heliograph, two-mirror
167
168
METHODS OF COMMUNICATION FOR FOREST PROTECTION
as the screen is entirely separate. On the other hand a single operator is in a much
better position to control the adjustment for sun motion during signalling when using
the British type than when using the American. This is because he can have both hands
on the two adjusting screws constantly, as one of them is used as the key to elevate
the mirror. This is important as the adjustment 'for sun motion is needed at extremely
short intervals and is often a serious handicap to one man when using the American
Army heliograph. The fact that an extra screen and tripod is required for the
American instrument is of little importance in station use and is more than offset
by the disadvantage of the greater number of small parts in the British models. The
latter also are more subject to difficulties in signalling caused by vibration in high
winds. This is serious, because most lookout stations are located where winds of con-
siderable violence blow more or less constantly. It is believed that for the best possible
results under all conditions a combination of the British type of instrument with the
American form of screen will give the greatest satisfaction. ' The screen should be
used only when vibration or other troubles render it necessary. It is to be noted, how-
ever, that this is a rather expensive equipment and would cost about twice; as much
as the Forest Service instrument alone, this last being considerably the lowest-priced
heliograph on the market.
Heliographs cannot be successfully employed on lookout towers. The reason is
that nearly all such towers vibrate excessively both as a result of wind and from the
movements of the operator on the platform. This vibration makes it impracticable
to keep a heliograph in adjustment. A platform on top of a lookout cabin or ranger
station if rigidly braced may be sufficiently free from vibration to be successfully
occupied for heliograph communication.
IOMI.
B oundary of California Notional
-^^r- Telephone lines in operation (Season 1912)
Main Lines of Heliograph Com mum 'car ion
Q Heliograph Centra/ Control Star ions
O He/Jogroph Substations
V Forest Supervisor's Headquarters
• District" Rangers Headquarters
Fig-. 104 Map of California National Forest, showing heliograph system .
Heliograph stations on mountain lookouts will generally be the most important in
the forest, and this use of the station should always be considered when equipping
a forest with a lookout fire-detection system. Direct communication between as many
stations as possible should be aimed at, and in addition one or more such stations
should be arranged to communicate with important headquarters on the. lower levels
which may be joined to the telephone system. An example of this kind is shown in
Fig. 104.
USE OF THE HELIOGRAPH 169
Section 103 — Heliographs on Patrol Routes
The use of heliographs by patrolmen or other moving units of a forest-protection
force brings up the question of light weight and ready portability, as previously men-
tioned. Such use is only practicable on a forest equipped with a permanent lookout
system for fire detection, and then only under topographic conditions which make it
readily possible for patrolmen to find points easily and quickly from which they can
open communication with lookout stations. This is not often practicable in a heavily
timbered region of little relief, but is easily accomplished in any rolling, hilly or
mountainous country.
For patrol purposes, the Godwin or Forest Service heliograph is the only practical
type. Its weight and size make it an entirely practicable equipment for any kind of
patrol and its range is sufficient for most forests where it might be employed. A use
for this instrument will exist wherever the standards of protection employed make it
impossible to secure rapid enough communication by message carried to the nearest
telephone station. Of course, the degree of development of the telephone system will
exercise a very considerable influence on this time interval, but as long as it remains
necessary to establish a physical connection with a telephone wire in order to use the
line and as long as maintenance charges remain as they are, very large areas in all
forest regions must necessarily remain without immediate telephone service. Con-
ditions may vary all the way from a protection staff which depends entirely on the
heliograph for intercommunication between all units to a staff which uses the helio-
graph merely as an emergency auxiliary, placing its dependence primarily on a tele-
phone system. The difference will result from the protection standards employed,
that is the maximum of average annual damage to which the protection system is
designed to restrict the forest fire loss.
CHAPTER XIX
USE OF THE GODWIN HELIOGEAPH
Section 104 — Parts of the Instrument
LIST OF PARTS
The complete instrument consists of a sole-leather case with shoulder-strap con-
taining: (a) One sun mirror, (b) one station mirror, (c) one screen, (d) one sighting
rod, (e) two mirror bars; the above in two padded wooden packing blocks; and (f)
one tripod with leather cup for points.
The heliograph and case is 10£ by 5J by 2£ in. outside dimensions and weighs 4
pounds 9 ounces. The tripod folded is 2 in. in diameter by 23£ in. long and weighs 7
pounds 3 ounces.
(a and b) Mirrors. — Two plane mirrors each 2| in. square are employed. These
are very carefully constructed so as to have both surfaces parallel, are backed with pure
silver, and varnished. Each is mounted in a black metal frame and swings in a yoke
on pivots at the sides. A slow-motion adjusting screw is provided by means of which
the mirrors when set up may be rotated on the line between these pivots as an axis.
This axis passes through the centre of the mirror. In the centre of each mirror there
is an unsilvered spot -fa in. in diameter. On the lower side of the yoke there is a
tapered stud which fits into a hole at the end of the mirror bar when the instrument
is set up. Both mirrors are exactly alike and may be used interchangeably, except
that when both are employed at one time it is necessary to paste a small white paper
disk in the centre of one of the mirrors on which to hold the " shadow spot." The
170 METHODS OF COMMUNICATION FOR FOREST PROTECTION
mirror thus equipped is then known as the "station mirror" and reflects the light to
the distant station. The other reflects the light from the sun to the station mirror
and is known as the "sun mirror." All metal parts are brass or aluminium bronze and
are finished in dull black.
(c) Screen. — The screen consists of a metal frame 4f in. square. Within this
frame, swung on pivots, the lines between which are horizontal, are four thin metal
leaves or vanes. At one side of the screen is a movable bar connected by levers to the
vanes in such a way that when it is pressed downward the vanes rotate on their hori-
zontal axis through an angle of 90° and thus open the screen. On releasing the bar,
a spring causes it to fly back to its original position and with it the vanes, thus closing
the screen. On the bottom of the screen frame is an angle foot by which it is attached
to the head of the tripod. Near the bottom of the sliding-bar is a small projecting
lug with a hole in it through which is passed a string by which the screen or shutter is
opened and closed while being used for signalling. An adjusting screw near the top of
the retractile spring enables it to be tightened if it becomes weakened through use.
(d) Sighting -rod. — This is a round metal bar S| in. long, flattened and pointed
at one end. To this flattened portion a small metal vane is pivoted which carries a
white target at the top for use in adjusting. This sighting-rod fits in a round hole in
one of the mirror bars in which it is held by a set-screw.
(e) Mirror Bars. — Two are required. They are similar in construction except
that the one used with the sun mirror has a hole near the tripod attachment for the
insertion of the sighting-bar, and a set-screw for holding it in place. This !bar is also
equipped with a tangent adjusting screw at the end, by means of which the mirror
mounted on it may be rotated on its vertical axis. The bare are 9 in. long, rectangular
in cross-section and enlarged at the end that fits on the tripod to a circle 2 in. in
diameter. At the other end, both have a round, tapered hole in which the studs on
the frames of the mirrors fit. A pivoted catch on the underside of each bar holds
the mirrors when in place. The slow-motion adjusting screw provided on one of
the bars together with the similar screw on the mirror enable the operator to rotate
the sun mirror simultaneously on both its vertical and its horizontal axes. These axes
intersect at the centre of the mirror at the point where the unsilvered spot is located,
and by means of the two adjusting screws the mirrors may be made to follow the sun
while the instrument is in use.
(/) Tripod. — A light but strong tripod with a flat, circular, brass head-plate is
provided. The cross-section of the legs is one-third of a circle, so that when folded
the tripod forms a neat cylindrical package. In the centre of the brass head is a
round hole in which is fitted a bolt having a three-wing nut at the lower end. The
upper end is provided with a lug. This lug fits in holes in the mirror bars and over
the angle foot of the screen, and by tightening the winged nut the various parts may
be attached firmly to the head of the tripod. A cylindrical sole-leather cup with strap
and buckle fits over the points of the tripod legs when folded for transportation.
Section 105 — Using the Godwin Heliograph
1 — SETTING UP
Set the tripod firmly on the ground with one leg toward the distant station and
the metal head as level as possible. A station heliograph on hard ground, rock, or a
wooden platform may have the legs set in pails, boxes, etc. filled with earth. To pre-
vent vibration in heavy wind, suspend a bag filled with sand or earth benea»th the
tripod so that it touches the ground just enough to keep it from swaying (Fig. 105).
In the Godwin type this cannot be done until setting up is completed as the weight
must be attached to the tripod head-bolt. Other types are provided with special
anchoring hooks for this purpose.
USE OF THE HELIOGRAPH
171
The position of the sun must be the guide for determining whether one or two
mirrors should be used. When the sun is in front of the operator (that is, in front
of a plane through his position at right angles to the line joining the stations) the sun
mirror only is required; with the sun in the rear of this plane both mirrors should be
used. When one mirror is used the rays of the sun are reflected from the sun mirror
direct to the distant station; with two mirrors, the rays are reflected from the sun
mirror to the station mirror, thence to the distant observer. Care should be taken to
note in which direction the sun is moving so that it may not be necessary to change
from one mirror to two while signalling-.
2— EMPLOYMENT WITH ONE MIRROR
Run the winged nut down to the lower end of the threaded shank of the head-
bolt. Push the bolt up through the tripod head and slip over the lug the main mirror
bar (the one with hole for sighting-bar), taking care that the side of the bar bearing
the maker's name is up and that the bar points directly away from the distant station
and back toward the operator. Turn the lug on the head-bolt at right angles to the
long axis of the mirror bar and slip under it the angle foot of the screen, so that as
Fig. 105 Forest ranger sending message by heliograph
you stand facing the instrument and the distant station the spring of the shutter is on
the right. To accomplish this, the angle foot of the screen must, of course, be inserted
from the side toward the distant station. The screen should be at right angles to the
mirror bar. Clamp both bar and screen firmly in place by tightening up the winged
nut.
172 METHODS OF COMMUNICATION FOR FOREST PROTECTION
Place the sighting-rod in the hole in the mirror bar and hold it temporarily in
place with the set-screw provided for that purpose. The pivoted vane bearing the
white target should face toward the operator. Turn this .vane down to the left. Pull
down the shutter key and wedge the shutter ppen by some simple catch. A weight
suspended on the end of a string tied to the pin on the sliding-bar of the screen will do.
Place one of the mirrors in the hole at the end of the bar and clamp in place by
the catch underneath the bar for that purpose. Turn the mirror so that it stands in
a plane parallel to the plane of the screen at right angles to the mirror bar.
Now eight through the hole in the centre of the mirror and over the point of
the sighting-bar in the same manner that the peep sight and the front sight of a rifle
are used, aiming at the distant station. These three points must be brought accurately
into line by adjusting the position of the sighting-bar and the mirror. To do this
loosen the winged nut on the head-bolt slightly and turn the mirror bar to the left
or right. At the same time raise or lower the point of the sighting-bar. It requires
some practice to perform this operation quickly. Care must be taken not to loosen
the head-bolt too much and disturb the attachment of the mirror bar and screen.
When these three points have been brought into perfect alignment, clamp head-
bolt and sighting-bar firmly, close the screen, turn the white target of the sighting-bar
to a vertical position and then, by means of the tangent adjusting screws on the mirror,
turn it on both its vertical and its horizontal axes until the small shadow spot cast by
the unsilvered spot in the mirror falls exactly in the centre of the white target. A sheet
of paper, held so as to intercept the reflected beam of light from the mirror about 6 in.
in front of it, will assist in locating the shadow spot and in bringing it on to the target
in this operation. The heliograph is now aligned and adjusted for signalling to the
distant station but it is extremely important to note that the shadow spot must not be
allowed to move off the centre of the target on the sighting-rod during operation.
3 — EMPLOYMENT WITH Two MIRRORS
When the sun is in the rear of the operator the second mirror and supplemental
mirror bar must be employed. Place the main mirror bar on the tripod head first, and
follow it with the supplemental mirror bar and the screen. Turn the supplemental
bar into the position occupied by the main bar When using one mirror only, and place
the screen at right angles to its long axis. In placing the screen, it should be put on
in the reverse position with the sliding-bar and key on the left side, as the operator
stands facing the distant station. Turn the main mirror far out in front of the screen
(toward the distant station) and slightly to one side. In this position the two bars
should form a wide obtuse angle. Place the two mirrors in position at the ends of the
bars, and clamp. The purpose of the front, or sun mirror is to reflect the sunlight on
to the station mirror from which it is reflected to the distant station. The front mirror
is preferably swung out to the left and the operator takes up a position behind it
where he is in easy reach of the adjusting screws and can readily watch the shadow
spot on the white disk in the centre of the station mirror. When operating from this
position, however, care must be taken not to permit the hand to cut off the light reflected
from the "sun mirror to the station mirror. A string or wire about 3 in. long with a
f-in. ring on the end, suspended from the lug on the sliding-bar of the screen will be
found to be the best equipment for operating a screen of this type.
Alignment with two mirrors is accomplished as follows: After setting up and
placing mirrors as indicated with the station mirror approximately facing the distant
station, the sun mirror facing the sun, and the screen wedged open, stoop down with
the head near and in the rear of the station mirror and look over its top into the sun
mirror. Turn the sun mirror by means of its adjusting screws until the whole of the
station mirror is seen reflected in the sun mirror and the unsilvered spot and reflection
of the paper disk accurately cover each other. Still looking into the sun mirror, adjust
the station mirror until the reflection of the distant station is brought exactly in lino
SIGNALLING WITH THE HELIOGRAPH 173
with the top of the reflection of the disk and the top of the unsilvered spot of the sun
mirror; after this the station mirror must not be touched. Now step behind the sun
mirror and adjust it by means of the tangent screws so that the shadow spot falls on
the centre of the paper disk on the station mirror. The flash will then be visible at the
distant station.
An alternate method of alignment is as follows: Stoop down behind the sun
mirror and while looking through the small hole in this mirror turn the station
mirror on its vertical and horizontal axes until the paper disk on the station mirror
accurately covers the distant station. Standing behind the sun mirror, turn it on its
vertical and horizontal axes by means of the tangent adjusting screws until the shadow
spot falls on the centre of the paper disk on the station mirror.
In operating the heliograph from a position behind the sun mirror the operator is
not as favourably placed for watching the distant station as when standing behind the
station mirror, but he is able to maintain his adjustment more perfectly and conven-
iently and on this account will generally secure more satisfactory results.
CHAPTER XX
SIGNALLING WITH THE HELIOGKAPH
Section 106 — Selecting a Station
Permanent stations will nearly always be selected with objects in view that take
precedence over the requirements of the signalling apparatus. Such stations may,
however, be improved artificially, if not entirely suitable.
Semi-permanent and temporary stations are occupied for signalling purposes
primarily and should be selected with this end in view. Stations should be selected so
that they are in full view of the station or stations it is desired to communicate with.
They should be located at as great an altitude as possible, especially when there is
difficulty about haze, smoke, dust, or undulations of the atmosphere noticeable on hot
summer days. A dark background is preferable for heliograph stations, so that it is
not always desirable to locate on the top of a conical peak which would probably ensure
a sky background. Select a station on the slope. Heliograph stations should be pro-
tected from the wind. This may be accomplished by setting up in the lee of a clump
of trees, a rock, or a building, but care must be taken to ensure that by so doing* the
shadow will not fall on the instrument at any period during the day.
Section 107 — Position of Operator
In operating the Godwin heliograph the operator stands directly behind the sun
mirror with the right hand holding the string by which the screen is opened and the
left on the tangent screws of the mirror. Both screws must be manipulated with one
hand and the rate and direction of movement depends upon the locality and the time
of day. By means of them the mirror must be made to follow the sun continuously;
this being accomplished by keeping the shadow spot on the centre of the target of the
sighting-rod or disk of the station mirror, as previously explained
In using the British Army type of heliograph the position of the operator is the
same, but with these instruments the key held in the right hand is also one of the
adjusting screws. The left hand holds the other. The operator is thus able to use
both hands for adjusting- while signalling. The shadow spot, however, falls on the
centre of the target only momentarily while a flash is directed at the distant station,
and not continuously as in the Godwin type.
In using the American Army type, the screen must sometimes be placed so far
from the mirror that it is difficult to reach both screen and adjusting screws at the
174 METHODS OF COMMUNICATION FOR FOREST PROTECTION
same time. This must be carefully guarded against in setting up the instrument, as
otherwise it becomes nearly impossible for one man to maintain proper adjustment
during operation.
When receiving a message the operator must be careful to remain in position at
his instrument so that he may interrupt the sending station if necessary. He must
also keep his heliograph in adjustment constantly both when sending and receiving.
Section 108 — Maintenance of Adjustment
The importance of careful attention to adjustment arises from the fact that the
lie-lit from a heliograph mirror is projected in the form of a cone, the lateral range
of which theoretically bears the same proportion to the distance between stations as
the diameter of the sun bears to its distance from the earth; that is approximately
1:107. Thus with the mirror aligned correctly on the distant station, the light will
be visible on either side of the station up to one-half of the distance between stations
divided by 107; for example, if the stations are six miles apart, the flash theoretically
will be visible about 50 yards on either side of the station. In practice, owing to
imperfections of mirrors, the lateral range is somewhat greater and the intensity of
the light is less at the outer edge of the cone than at its axis. This fact together with
the very small lateral distance in wnich the light is visible, makes it essential that
for the best results the alignment bu made carefully so as to have the axis of the cone
of light strike the distant station, and the adjustment maintained constantly. Perfect
adjustment is secured only by keeping the shadow spot uninterruptedly in the centre
of the paper disk, and, as this spot continually changes position with the apparent
movement of the sun, when two men are at a station, one should be in constant attend-
ance on the tangent adjusting screws. When working alone, operators must watch
their adjustment very closely to ensure that the light reaches the distant station. A
little practice will soon show how far the spot may move from the exact centre of the
paper disk before the flash becomes invisible at the other station. Extra care bestowed
upon preliminary adjustment is repaid by increased brilliancy of flash. Remember,
the distant observer is unquestionably the better judge as to the character of the flash
received; and if, therefore, adjustment is called for when the shadow spot is at the
centre of the disk, the alignment is probably at fault and should be looked after at
once.
Section 109 — Opening Communication
In forest protection the locations of all permanent heliograph stations will be
known to all members of the force. To attract the .attention of a station once the helio-
graph is aligned on it, send a succession of flashes until answered. The heliograph flash
is strikingly noticeable, but attempts to attract attention, to be successful, must be
persistent. They should never be abandoned until every device has been exhausted.
When acknowledged, each station will then turn on a steady flash and1 adjust. When
the adjustment is satisfactory to the station called, it will cut off its flash and the call-
ing station will proceed with its message.
The exact location of semi-permanent stations, especially when placed at a low
level, is sometimes difficult. The compass bearings of all such stations from the helio-
graph stand should always be taken by each permanent station operator. A still better
method is to set two stakes about twenty yards apart with the tops directly in line with
the distant station, marking on the far stake the name of the station that it indicates.
Where stations are so located that smoke from forest fires is likely to obscure them, a
whole series of such guide-line posts should be permanently erected showing the line to
each station within the range of communication. With such, stakes accurately aligned
it is then possible to call any station within range even though the station may be
temporarily obscured by smoke. To call under these circumstances, loosen the catch on
the underside of the mirror bar and rotate one of the mirrors by hand until the flash is
SIGNALLING WJTE THE HELfOGRAPH 175
seen to pass directly across the tops of the two range stakes. Move slowly back and
forth in the azimuth in which the station is known to lie until the call is acknowledged.
Then adjust on the flash from the distant station and proceed with the message.
Section 110 — Working at Short Ranges
At ranges up to about 10 miles, it will be found that the flash from the heliograph
is extremely tiring to the eyes. For short ranges with 4-in. or larger mirrors, cover a
part of the station mirror with a pasteboard disk having a hole in the centre 2-in. in
diameter, or wear smoked glasses. Lookout men will generally be equipped with
coloured glasses 'and should wear them when reading heliograph signals. The heliograph
is more rapid and, at any but very short ranges, is more easily read than the flag, but it
has various disadvantages that will not ordinarily cause it to be preferred to the flag at
ranges under five miles unless it is necessary to signal through haze or smoke. For very
short ranges, the flag described in chapter XXII will be found preferable to the helio-
graph and more generally available.
Section 111 — Working through Haze and Smoke
A remarkable and extremely valuable property of the heliograph flash in forest
protection is its ability to penetrate smoke. This increases with increase in size of the
mirror. With the standard American Army 4^-in. mirror the author has read1 signals
with the naked eye at a distance of 15 miles, when even the outlines of the mountain
peak on which the sending heliograph was located could not be distinguished because
of smoke from forest fires. At the same time this station was in continuous communica-
tion with another, 30 miles distant, although neither was for days able to sjc the
mountain on which the other was located. This property, of course, has its limita-
tions and very dense smoke will make heliograph communication impossible but prob-
ably not till long after location of fires by lookout men has become fully as imprac-
ticable.
Section 112 — Heliograph Codes
Four different codes have been used for heliograph signalling. These are:
(1) American Morse Code, (2) International Morse Code, (3) Myer Code, (4) Alpha-
betical Square Code.
1 — AMERICAN MORSE CODE
This code is only used for telegraphic communication in the United States and
Canada. It is distinguished from the International Morse code by the "space" or
"pause" used between the elements of certain letters. It is not now used for visual
signalling although it may be so employed if desired, but has no advantages over other
codes.
2 — INTERNATIONAL MORSE CODE
This is the telegraph code used generally throughout the world except in the
United States and Canadian telegraph services. It is also called the Continental code
and is the code most commonly employed for heliograph signals. All letters consist of
combinations of dots and dashes. With the heliograph these are made by short and
long flashes.
The dash is represented by a flash of about two seconds' duration.
The dot is represented by a flash one-third as long.
The interval between flashes should be one-half second.
The interval between letters, one second.
The interval between words, two seconds.
176 " METHODS OF COMMUNICATION FOR FOREST PROTECTION
INTERNATIONAL MORSE ALPHABET
Ar — N
B - O -
C - P -
D - Q -
E - R -
F - S -
G - T -
H - U -
1 - - V -
T W
?J V V "
K - X
L - Y
M - Z -
NUMERALS
1- 6
2 - 7 -
3 8
4 - 9 -
5 0 -
SHORT NUMERALS
1 6
2 -
3
4 9_
5 - 0 -
The short numerals are only used in telegraphy in the repetition of figures.
PUNCTUATION
Period Exclamation
Comma Apostrophe
Interrogation Semicolon
Hyphen or dash Colon
Parenthesis Cross
Quotation mark -
CONVENTIONAL SIGNALS
End of word Interval (2 seconds).
End of sentence. Double interval (period).
End of message Triple interval (cross).
Acknowledgment, or I understand R
Error
Repeat after (word) Interrogatory (word).
Send faster Q R .Q
Send slower Q R S
Cease sending QRT
Wcnit a moment
Move to your right MR
Move to your left ML
Move up M U
Move down . M D
SIGNALLING WITH THE HELIOGRAPH 177
It will often be found very advantageous to substitute for the conventional sig-
nals given above, the following : —
End of word 1 extra long flash (about three times the
length of a dash).
End of sentence 2 extra long flashes.
End of message 3 extra long flashes.
Although this slows up the transmission it is a great help to poorly trained
operators, and is particularly valuable when sending code messages where it is
impossible to make out the proper spacing from the context.
This code is used for signalling with the heliograph by the British and Canadian
military forces and will probably be the one best adapted for use in Canada in forest-,
protection communication. It is adapted not only to visual but also to electric tele-
graphic signalling and radio work.
3 — MYER CODE
This code was formerly used by the United States Army for visual signalling and
is still employed in certain districts by the United States Forest Service. In this code
there are three elements, generally designated, 1, 2, and 3. All letters are made up of
combinations of 1 and 2; 1 being a short flash; 2, two short flashes in quick succes-
sion. 3 is a long flash, like a dash of the International Morse code, and is used to
indicate certain pauses and in conventional signals. This code has certain advantages
for heliograph work, although it has now been pretty generally abandoned in favour
of the more generally useful International Morse code.
MYER CODE ALPHABET
A 22 O 21
B 2112 P 1212
C 121 Q 1211
D 222 K 211
E 12 S 212
F 2221 T 2
G 2211 U 112
H 122 Y 122-2
I 1 W 1121
J 112-2 X 2122
K 2121 Y Ill
L 221 Z 2222
M 1221 Question 1112
N 11
NUMERALS
1 1111 6 2211
2 22'22 7 12>22
3 1112 8 2111
4 2221 9 1221
5 . . 1122 0 2112
ABBREVIATIONS
A After T The
B Before U You
C Can Ur Your
H Have W Word
N Not Wi With
K Are Y Yes
79211—12
178
METHODS OF COMMUNICATION FOR FOREST PROTECTION
CONVENTIONAL SIGNALS
End of word. .3.
End of a sentence. .33.
End of a message. .333.
Acknowledgment,
or I understand. .22 22 3.
Eepeat last word. . 121 121 33.
Repeat last message. .121 121 121
Wait a moment. .1111 3.
Signal faster. .2212 3.
Cease signalling. .22 22 22 333.
4 — ALPHABETICAL SQUARE CODE
This code is constructed according to a very simple rule which may be easily
remembered, so that it is possible to improvise the entire code at any time. Aside
from this it would not appear to "have any marked advantage over other codes. The
code is made by arranging the letters of the alphabet in five vertical columns of five
letters each, K being omitted and C substituted for K wherever it occurs. Each letter
is then represented by a number of two places, the first figure being the number of
the column in which the letter occurs, counting from the left toward the right, and
the second its place in this column counting from the top downward. This arrange-
ment is as follows : —
1
2
3
4
5
1
a
f
1
q
v
2
b
g
m
r
w
3
c
h
n
s
X
4
d
i
0
t
y
5
e
j
P
u
z
The alphabet follows: —
a=l-l f=2-l
! g=2-2
l-5
i=2-4
j=2-5
1=3-1
n=3-3
o=3-4
p=3-5
q— 4-1
r=4-2
s=4-3
w— 5-2'
x=5-3
u=4-5
z=5-5
Each letter is made by sending short flashes only, to the number of each cf the
two elements of the letter, with a short pause amounting to one beat of time between
these elements. A pause of two "beats of time is allowed between the letters, and
between words there is either a pause of three beats or the long flash may be used, as
with the 'Myer code. The latter is to be preferred with poorly trained operators.
Thus the letter M (3-2) would be represented by three short flashes, a pause of one
beat of time, and then two short flashes. Experiment has shown that a message may
SIGNALLING WITH THE HELIOGRAPH 179
be sent with this code quite as rapidly as with the Myer code and only a little
less rapidly than with the International Morse code. The fact that each letter con-
sists of only two symbols, and that only dots are sent and no dashes, makes it an easier
code to send intelligibly and to read. The further fact that it is made according to
a simple rule as already explained, is an advantage in forest-protection work, where
the use of the heliograph is confined to a limited portion of the year and where
operators will generally not be able to keep in practice. In the district where this
code is employed for forest-protection communication the following numerals and
conventional signals have been adopted: —
NUMERALS
B 1 G
C 2 H
D '. . 3 I
E 4 J
F . . 5 M
CONVENTIONAL SIGNALS
End of word Interval (2 seconds)
End of sentence or message. . 1-6 Wait a moment 6-1
I understand 2-6 Signal faster 6-2
Repeat last word 3-6 Cease signalling 6-3
Repeat last message 4-6 I wish to use message code . . 6-4
Section 113— Instructions to Operators
In sending with the heliograph it is of the utmost importance that uniformity
in mechanical movements of the screen be cultivated, as lack of rhythm in the signals
of the sender entails unnecessary and vexatious concentration of attention on the
part of the receiver.
The first position is to turn a steady flash on the receiving station. The signals
are made by long and short flashes. Use <a short flash for dot and a long steady flash
for a dash. The elements of a letter should te slightly longer than in sound signals.
To call a station. — Send a rapid succession of short flashes until acknowledged.
Each station will then turn 011 a steady flash and adjust. When the adjustment is
satisfactory to the called station it will cut off its flash .and? the calling station will
proceed with its message.
Adjustment. — If the receiver sees that the sender's mirror needs adjustment, he
will turn on a steady flash until answered by a steady flash. When the adjustment
is satisfactory the receiver will cut off his flash iand the sender will resume his
message.
To break or stop the signals from the sending station. — -Make a rapid succession
of short flashes without pause until the sender stops sending.
To start the sending station after IreaHng. — Turn on a long flash and he will
commence at the 'beginning of last word.
To acknowledge receipt of a message. — Signal - - followed by the name
of the receiver.
If the sender discovers that he hus made an error he should make a rapid succes-
sion of short flashes, after which he begins with the word in which the error occurred.
To lessen liability of error, numerals which occur in the body of a message
.should be spelled out in full.
79211—12*
180 METHODS OF COMMUNICATION FOR FOREST PROTECTION
A record of the time of receipt and transmission of every official message should
be kept.
In receiving messages nothing should be taken for granted and nothing con-
sidered as seen until it has been positively and clearly in view. Do not anticipate
•what will follow from signals already given. Watch the communicating station until
the last signals are made and be very certain that the signal for the end of a message
has been given.
Attempts to attract the attention of a station to be successful must be persistent.
They should never be abandoned until every device has been exhausted.
Section 114 — Care of .Instruments
(1) When riding always carry the heliograph slung across the shoulders and not
attached to the sad'dle. On a pack-horse it should 'be rolled in the shedding.
(2) Never leave the heliograph on its stand when the work with it is finished.
Dismount and replace in its case.
(3) Avoid holding the instrument 'by the U arms or mirror frame.
(4) If the heliograph gets wet, rub the metal portions over with an oily rag
before putting it away or at the first opportunity.
(5) Always keep the heliograph clean and free from rust and dust. Grit and
dust in the tangent screws or sockets of the mirror bars will soon destroy the best
instrument.
(6) Occasionally oil the working parts (screen, sliding-bar, vanes, tangent
screws, bearings, etc)j but never leave superfluous oil on any part, as it collects duet.
(Never allow oil to drop on the mirror.
(7) Make adjustments of the bearings, etc., only when necessary. Be careful
not to damage or burr the heads of screws, and see that the threads are not crossed
or otherwise mutilated.
(8) Before commencing any minor repairs, consider by which means the fewest
screws and parts need be removed. Avoid stripping the heliograph on ground where
the parts would be easily lost, such as in long grass, elc. If possible spread a blanket
or pack cover on which to work.
Section 115 — Training Operators
The following, taken from " Systematic Fire Protection in the California
.Forests ", corresponds with the author's experience, and is quoted1 as a suggestion
to those who may undertake to employ the heliograph in forest protection: —
" It has been proven by experience that the average mountain man selected for
lookout service is quite capable of learning and becoming proficient in the use of the
heliograph. The first step in installing this system on a forest should be to secure
the services of an experienced instructor to train the new men.
" In heliograph work, practice is absolutely essential to fast and intelligible
signalling. A common fault is the failure to keep the mirror in perfect adjustment
while operating. This fault is extremely annoying to the receiving station and
must be eliminated. The .actual spelling out of words is not the difficult part; the
trouble comes in at the ends of words, ends of sentences, ends of messages, getting
started, failure to observe the conventional methods of calling, breaking signals,
starting again, acknowledgment of messages, etc. It is only through constant drill-
ing, as in the case of telegraph operating, that the heliograph man learns these
tricks of the trade.
" The average speed attained by the best Forest Service operators has been
found to be about four words a minute. The average fire message need not exceed
twenty words, so it will ,be seen that after the discovery of a fire an expert heliograph
:nan can get the news to his receiving station in five minutes. Twice this length of
time should! be a safe figure for an ordinary operator."
SIGNALLING WITH THE HELIOGRAPH 181
Heliographs have only once been employed in forest protection in Canada. There
is no reason, however, why they would not be extremely useful. Suitable atmospheric
conditions prevail throughout the western forest regions, especially in Alberta and
the interior of British Columbia and during most of the summer throughout the
east and north.
One ameliorating circumstance in connection with the impossibility of using the
heliograph except in full sunlight lies in the fact that with rain or overcast sky
the need for using it in connection with forest protection is likely to be very much
reduced. Successful utilization of this instrument, of course, requires the employ-
ment of interested and intelligent men and a higher degree of organization and
discipline in the protection staff than has heretofore been thought necessary.
The learning of the alphabet can be taken up indoors by using an inexpensive
telegraph key and sounder installed with a telephone dry cell. Practice should be
continued until the letters, numerals, and conventional signals are thoroughly
mastered.
The operators should then be practised on the heliograph itself and taught to set
up quickly and align accurately. Men can practise singly in maintaining alignment
and also in cultivating rhythmic sending "by directing the beam toward an ordinary
mirror set up at a distance of about 100 ft. and placed so that the flash is reflected
back to the sender.
When the alphabet has been thoroughly learned and a good sending-speed devel-
oped, a practice range equipped with telephones should be installed. The distance
between said stations may be as long as conditions warrant but should, if possible,
be at least half a mile. If an existing telephone line cannot be tapped, a temporary
line may be built with emergency wire if available. On this range with two instru-
ments a number of men may be taught to receive messages, to send messages, and,
especially, they may be given practice in the various "tricks" of sending and receiving
that generally prove most difficult for beginners. The telephone serves to keep the
instructor in touch with both sets of men and enables him to correct mistakes of
sending with the least difficulty.
For use at night or on dull days when the heliograph cannot be operated a couple
of signal-lanterns will be found highly convenient for instructional and practice
purposes.
Section 116 — Heliographing- by Moonlight and Artificial Light
The heliograph ^ has been used to send messages by moonlight but the range is
extremely limited. It cannot be depended upon at any ordinary forest range.
Artificial light may also be employed, the range depending on the strength of the
light. Only short ranges as a rule may be attained. When using an artificial light
with the fixed-flash heliographs it will generally be found more satisfactory to employ
the screen only, rather than attempt to reflect the light from the mirror.
CHAPTER XXI
NIGHT SIGNALLING
Section 117 — Signalling-lanterns
Although the variety of lanterns available for night signalling is very great, the
actual use of such equipment in forest-protection communication has been extremely
limited. 'Signal-lanterns .are of two principal types, those which form code letters
t>y the display of two colours in the proper sequence, and those which form code letters
by flashes of one colour only, showing dots and dashes as with the heliograph. The
range of the first class is entirely too short to be of any use in forest protection. The
second class offers greater possibilities.
Flash lanterns for signalling purposes are available, using as the source of light
acetylene gas, oil, gasolene, limelight, and both incandescent and electric arc lamps.
Two principal types are employed; those which burn continuously and operate with a
screen like a fixed-flash heliograph, and those which operate with a key and burn
intermittently only. The oil, gasolene, limelight, and arc lamps are of the first type.
The acetylene and incandescent lamps are of the second type.
1 — TYPES OF SIGNAL-LANTERNS
'Signal-lanterns of various forms are employed principally for military and naval
communication purposes. The ordinary electric searchlight makes an excellent signal-
lantern and can be used either behind a screen for the sending of Morse signals, or
the beam can be used to send wigwag signals even between stations that are not them-
selves intervisible. It is not, however, a practical lamp for forest communication
because of the large amount of power required for its operation, not to mention its
great weight and lack of portability.
Among readily portable signal-lanterns two principle types are available. These
are the acetylene lantern, and the electric signal-lantern using dry cells as a
source of power. Both have to a limited extent been employed in forest-protection
communication.
(a)» Acetylene Lamps. — The acetylene signal -lantern is used extensively by the;
American Army Signal Corps, and the most read'ily procurable lanterns of this
type are those adopted by that Service. Two sizes, the field lantern and the station
lantern, are employed. For lookout use the station lantern, which is the larger, is
preferable as it is as readily portable as the requirements of this service demand
and has by far the longer range.
This lantern is built in 4he form of a small searchlight with a 5-in., aplanatic
lens mirror and S-in. focus. It is mounted on a 'suitable tripod .and equipped with
a special gas-generator, a sighting-tube, and a small reading-lamp, the whole equip-
ment weighing about 20 pounds. The generator is hung to the legs of the^tripod
beneath the lantern and is charged with 1 pound of calcium carbide and 1 gallon of
water. This charge is sufficient for about 5 "hours' -signalling, and recharging
requires only a few minutes.
The sighting-tube in the form of a small telescope is attached to one side of the
lantern. It is provided with cross-hairs and i-s used to direct the beam of light on
the distant station. Once the lantern is properly aligned, it requires no furtl.
adjustment, in which respect it is much superior to the heliograph.
The supplementary reading-lamp is required with all forms of 'signal-Ian terns,
as the intermittent flashes of the signals do not afford light enough for reading or
recording messages. It is an acetylene lamp also, securing gas from the generator
that supplies the signal-lantern.
182
SIGNALLING
183
This form of lantern may be used with a screen similar to the heliograph screen,
but to do so the light must burn continuously during signalling. This more than
doubles the consumption of carbide, since one charge of the generator will furnish
gas for only 2 hours' continuous light. The speed of operation with a screen is eight
to fourteen words per minute.
Fig. 106 Acetylene signal-lantern with tripod
As usually employed, the screen is dispensed with and a special form of key
is used which controls the supply of gas to the burners. A small amount of gas
is admitted continuously. Depressing the key causes a full flow of gas to be admitted
to the burner, giving a bright flash lasting as long as the key is held down. The
response to the key is instantaneous. Operated in this manner, less carbide is used
but the speed is slightly reduced, being about five to ten words per minute. Smoke,
fog, rain, and also bright moonlight are the principal impediments to the use of this
lantern. The range under ordinary conditions of operation does not exceed 30 miles
when viewed with a telescope, and about half this when observed with the naked eye.
(ft) Electric Lamps. — For comparatively short-distance work the electric signal-
lamps, such as are used by the British Army, are very convenient. Such a lamp is
the Stevens-Lyon lamp, manufactured in London. This lamp weighs 10* pounds
184
METHODS OF COMMUNICATION FOR FOREST PROTECTION
complete and may be mounted en a heliograph tripod. It can be easily read without
a telescope at 11 miles. The source of power in electric lamps such .as this is the
dry cell. In order to reduce battery consumption, all signal-lamps of this character
operate with a key or switch, by means of which the circuit is made and broken in
such a way as to form the letters of the Morse code. In the Stevens-Lyon lamp
this key is placed on the top of the lamp and is shaped like the ordinary Morse
key used in telegraphy. A sighting-tube and a small oil reading-lamp are also
provided and serve the purpose already described. This is a very compact, easily
portable and easily operated lamp, and within the limits of its range might often be
preferred to the acetylene lamps.
For use with it the inert type of dry cell is made up with the excitant in the
form of a dry powder instead of the paste used in the ordinary dry cell. Cells of
this type are made ready for use by adding water through a tube placed in the cover
for the purpose. They have the great advantage of not deteriorating even when
kept stored for long periods. Such cells, however, are not read'ily procurable and
as a rule can be obtained on special order only.
Fig. 107 Fischer high-power electric signalling lamp
(c) Fischer High-power Lamp. — The most promising signal-lamp thus far pro-
duced is the Fischer triangulation lamp used by the United States Coast and
Geodetic Survey as a night signal on its triangulation stations. This lamp employs
an 11-in. reflector and, although not as yet fully perfected as to details, it is believed
it can be produced1 to weigh about 24 pounds and to cost under $50, without the dry
•cells. Eighteen cells are employed to furnish the current and these will give about
9 hours' continuous service. A-s used intermittently in signalling they will last a
considerably longer period, depending on the amount of such use.
This lamp has the usual sighting-tube, reading-lamp, and switch-key. Its dis-
tinguishing feature is a -specially designed, gas-filled bulb having a highly concen-
trated filament which, with a 6-volt, 2<i-ampere current, gives 260.000 ^apparent
can<Jle-power at 100 ft. The range of this lamp under ordinary conditions is 50 to
NIGHT SIGNALLING 185
75 miles, no telescope being employed, while under exceptionally favourable condi-
tions of atmosphere it has been seen with the naked eye at 100 miles. On a dull day
it can be used up to 10 or 15 miles. As with other electric lamps, the speed of
sending is somewhat reduced because the filament requires an appreciable time to
heat up and cool off. About five words per minute can be sent efficiently.
This lamp with the large number of dry cells required for its operation is not a
rea'dily portable equipment and would only be suitable for permanent stations. Diffi-
cult accessibility would indicate a necessity for employing either wet batteries or the
inert type of dry cell, in preference to the ordinary type.
2 — USE IN FOREST PROTECTION
Thus far the only use made of signal-lanterns for forest-communication purposes
has been on an experimental basis by the United States Forest Service in the state
of Washington. Certain advantageous uses for aii efficient lamp for lookouts are,
however, apparent. The ease with which lamps ma»y be used by one man, requiring,
as they do, no adjustment after once being properly aligned, makes them especially
valuable for training operators to send and receive flash signals, and for assisting
trained men to keep in practice. Of course, the signal-lantern as a means of lookout
communication is subject to nearly the same general limitations as is the heliograph,
and it cannot be considered as the principal communication equipment on important
stations in preference to the telephone, nor can it be depended upon to replace the
heliograph. Practically all fires are detected during the day and where visual signals
a^e depended upon for communication the principal methods must be available for
daylight operation.
Signal-lanterns, however, can be operated from towers, while heliographs cannot,
and, owing to the more uniform conditions that prevail at night, they are the most
reliable of all means of visual signalling.
Although, as stated, the use of signal-lanterns in forest protection is as yet very
limited it would seem that a lantern with sufficient range would find the following
application : —
1 To serve about the same purposes at night that the heliograph and flag serve
during the day, that is, to afford communication on lookout stations before the instal-
lation of the telephone, during temporary interruptions of telephone service, or on
intermediate temporary stations which are not of sufficient importance to justify
the provision of telephone equipment, or stations being occupied experimentally.
2 To serve as a specially convenient instrument for training and practice in the
sending and receiving of flash signals.
3 To make possible the speedy report of fires detected just before sunset. These
are particularly numerous in regions where much land clearing is going on.
4 To make possible the speedy report of such fires as are detected at night. Night
detection is, however, rare.
5 On a dull day when the heliograph cannot be employed the lantern may be
used for short-range communication. With the Fischer lamp, daylight signals may
be sent about 10 miles.
6 To report at night, fires that were detected during the day but could not be
reported immediately because lack of sunlight prevented the operation of the helio-
graph. Also, messages not urgent in character, such as orders for supplies, personal
messages, etc., may be sent at night.
The signal-lantern is inferior to the heliograph in the following respects:—
1 Its daylight operation is very uncertain and very limited in range.
2 It cannot be used for communication with a moving patrol because of the
practical impossibility of picking up stations at night unless their position has been
determined and sighted Upon before nightfall.
186 METHODS OF COMMUNICATION FOR FOREST PROTECTION
3 It is slower in operation. This, however, is probably more than offset with
poorly trained operators by the fact that once aligned the lantern needs 110 further
adjustment.
4 At mountain lookouts and other stations difficult of access, the providing of
sufficient electric cells or other source of light may be inconvenient.
The signal-lantern, therefore, can be successfully used only as an adjunct to
the heliograph in situations where the latter is the principal or only means of com-
munication, and only for the purpose of communication between lookout stations or
from a lookout to a lowland headquarters on the telephone system. For this purpose
a ]amp with a great range, a moderate weight, and a reasonable first cost and power
charge is essential. These requirements would seem to be met best by the Fischer
triangulation lamp of the United States Coast and Geodetic Survey.
CHAPTER XXII
FLAG
Section 118 — General Remarks
The flag as a means of communication is far less applicable to forest protection
than to military operations. Its principal value lies in the extreme simplicity and
cheapness of the equipment required1, and in the fact that it may be readily impro-
vised and can therefore always be available. It is, further, a convenient signalling
device with which to instruct new men and keep trained men in practice. The range
over which it may be used is so limited, however, that in most forest work the place
it might occupy will be taken by either -an emergency telephone line or a messengei
service.
The flag is a day signalling device like the heliograph, but unlike the latter it-
can be employed on dull days as direct sunlight is not essential. Dust and smoke,
however, very greatly limit the range of flag signals, and may act .as a serious obstacle
to their employment.
Section 119 — Equipment Required
Flags should be of linen or cotton cloth or some similar smooth material. Gala-
tea and near-silk serve admirably. The colours used depend on the background
^against which the signals are being made. Dark blue is best for a light background;
white with a blue or red strip or square in the centre, for a dark background'. Sizes
used depend on the distance, and run from 2-ft. square to 6-ft. square, which latter
is about the largest practicable -size. For forest use, it is unnecessary to provide
poles, but one edge of the flag should be provided with tapes at intervals of 12-in. by
which the flag can be attached quickly to a light pole, cut as required. For tem-
porary stations, flags are preferably made of some mercerized' cotton cloth in order
to reduce weight and bulk. Two :l-ft. flags of this material can be rolled into a
package the size of an ordinary dry cell and will weigh 12 ounces.
Section 120 — Range and Speed
In military operations, flags are generally read with field-glasses or telescopes.
This is seldom practicable in the communication work required in forest protection,
The distance at which flags of a given size can be read depends on the nature and1
cdour of the background., the state of the atmosphere, and the power of the telescope
employed. The greatest distances are possible on days with -a clear atmosphere but
the sky lightly overcast with clouds. Lack of sunlight does not prevent the use of
flags as it does the heliograph. 'Smoke and fog, (however, are more or less complete
THE FLAG 187
obstructions, according to their density. On the average, wigwag signals with a 2-ft.
flag may be read with the naked eye at a distance of 2 J miles, with a 4-ft. flag at 4
miles, with a 6-ft. flag at 7 miles, and with six-power binoculars at 4 miles, 7 miles,
and 10 miles, respectively. More powerful glasses or exceptionally clear atmosphere
will extend these distances somewhat, it being generally possible to read a 6-ft. flag
nt 10 miles with the naked eye in Western Canada. Semaphore signalling with the
2-ft. flags can be read only about 1 to 2 miles.
The speed of sending with flags is greatest with the small fla-^s, using the sema-
phore alphabet, and least with the very large flag, using wigwag. The former method
cnu be operated at ten to fourteen \vords per minute, the latter at onV four to six
words depending on the size of the flags employed.
Section 121 — Use in Forest Protection
Except for instructional and practice purposes, as already indicated, the employ-
ment of flags in forest signalling is likely to be limited. The conditions under which
they are most likely to prove useful are the following: —
(a) Across Impassable ^Barriers. — Pack outfits on opposite side? of large rivers in
flood, and parties unprovided with canoes on opposite sides of lakes, often find a means
of communication very desirable.
(fr) Lookout Station to Headquarters. — When the distance is short and no other
means of communication is available, flags may sometimes be employed between
permanent lookout stations and district ranger or " smoke chaser " stations at lower
levels. This is seldom likely to occur as it assumes that neither the telephone nor
heliograph is available.
(c) Patrolmen to Lookout 'Stations. — The extreme portability of the flag makes
this use readily practicable and it may often be valuable. An urgent message can
thus be sent from a point 5 to 10 miles from the lookout station which might otherwise
have to be conveyed by messenger. In a mountain country with the lookout station
011 a high peak this might involve much time.
In case the attention of the lookout man cannot be attracted with the flag alone,
smoke puffs or a small hand'-mirror should be used for this purpose. Smoke puffs are
made by kindling a small, hot fire and, after it gets a good start, covering it with green
grass, leaves, or damp, rotten wood, or earth. A 'blanket or pack cover should be
thrown over this and the smoke released in puffs.
A much better method is to carry in the outfit a good plane mirror about 3 or 4
in. square. 'Set two stakes so that their tops are accurately in line with the distant
station and use these as sighting points in directing the flash on the lookout station.
Keep the flag displayed meanwhile, and when the lookout man acknowledges the call'
by raising his flag or turning on his heliograph proceed with the message.
(d) Heliograph Stations to Camps. — Heliograph and other long-distance signalling
stations are necessarily placed on elevated points while camps are as a rule in valleys,
close to water. It quite frequently happens that the heliograph operator receives a
message for the camp foreman to which a reply is expected. This ordinarily involves
a trip to camp to deliver the message and a return trip to send the reply. Such
distances are usually short, but may be a mile or more, and if the two points are
intervisible this delay can be avoided by the use of the flag.
(e) On Forest Surveys.— A great deal of time is often lost in survey work because
the members of a working party are too far apart to make themselves heard in giving
instructions. It is true that much of this is due to poor organization or to poorly
trained assistants, but some of it is unavoidable. This is especially true in open
country where the members of a party may be a long distance apart, The small flag
under these circumstances can be of great value in conveying simple instructions over
very much greater distances than the voice will carry.
CHAPTER XXIII
USING THE FLAG
Section 122 — General Remarks
Flag signals are made by either the semaphore or the wigwag system. The former
is the more rapid but the latter has by far the greater range, and is the method best
adapted to forest-protection uses. Several methods of wigwagging are employed but
all agree in having at least two distinct movements of the flag, one representing a dot
and the other a dash of the Morse code. A third motion is ^employed in certain con-
ventional signals as is the long flash or " 3 " of the IMyer code with the heliograph.
The wigwag system which employes motions both to right and left is best adapted to
the larger flags and therefore to the longer ranges, and should be employed for forest
work, although other more rapid methods for short-range work can be easily acquired
subsequently.
Section 123— Selecting a Station
The general principles stated in iSection 106 for the selection of heliograph stations
also apply to flag stations. With the latter, greater care must be exercised in determin-
ing the colour of the background, since this has a- very great influence on the range at
which signals may be read.
To determine the colour of the background, first ascertain whether the com-
municating station is higher or lower than, or on a level with, your own. If it be
higher, the background for your signals, viewed thence, will be the colour of the field,
woods, etc. behind, and lower than, your flagman. If it be lower, your background will
be the colour of the ground, etc. behind, and higher than, your flagman. If the sta-
tions are of equal elevation, then the background for your signals will be that directly
behind the flagman.
The colour of the flag must contrast as strongly as possible with that of the back-
ground. With green or drab, or with earth-covered background, the white flag should
be used. The distant station is the best judge of background, and should it indicate
the colour of flag wanted, that flag should be used.
The following table shows the extent of horizon for different heights above sea-
level; that J8, it shows how far an object at the sea-level can be seen.
DISTANCES AT WHICH AN OBJECT AT SEA-LEVEL CAN BE SEEN
Height of
the eye
above sea-
•Distance
in
Height of
the eye
above
Distance
in
Height of
the eye
above
Distance
in
Height of
the eye
above
Distance
in
level in
statute
sea-level
statute
sea-level
statute
sea-level
statute
feet
miles
in feet
miles
in feet
miles
in feet
miles
10
4
50
9
115
14
300
23
15
5
60
10
130
15
350
25
20
6
70
11
150
16
500
30
30
7
85
12
200
18
700
35
40
8
ion
13
230
20
900
40
According to the above fig?ires, an observer whose eye is 30 ft. above sea-level can
distinguish an object 7 miles disHnt, providing it is at the sea-level; but if the object
is if self 15 ft. aibove the se# he can make it out 7 miles + 5 miles = 12 miles.
188
USING THE FLAG
189
Section 124 — Wigwag Signalling
Flag, torch, hand lantern, or the be-am of a searchlight may be employed.
1 — MOTIONS
One position and three motions are used. The one position is with the flag or
other appliance held vertically, the signaling n facing directly toward the station with
which it is desired to communicate.
The first motion (the "dot" of the International Morse code or "1" of the Myer
code) is to the right of the sender, will embrace an arc of 90° starting from the
vertical and returning to it, and will be made in * plane at right angles to the line
connecting the two stations.
The second motion (the "dash" of the Internationa? or "2" of the Myer code) is a
similar motion to the left of the sender.
The third motion ("front" or "3" of the Myer code) is downward directly in front
of the sender and instantly returned upward to the first position. This is used to indi-
cate a pause or conclusion.
Fig 108. Initial position
2 — HANDLING THE FLAG
Make all motions rapidly. To prevent entangling of the flag on its stuff, skilful
handling acquired by practice is necessary. It is accomplished by making a scoop of
the flag against the wind, the movement describing an elongated figure 8, thus 00. The
motions should be made so as to display in the lateral waves the whole surface of the
flag toward the point of observation.
190 METHODS OF COMMUNICATION FOR FOREST PROTECTION
Fig. 109 "Dot" or motion "I1
Fig. 110 "Dash" or motion "2"
USIXG THE FLAG 191
Section 125 — Rules for Operators and Conventional Signals
(a) To call a Station. — Wave the flag through an arc of 180° in a plane at right
angles to the line connecting the two stations until acknowledged (or make the
station's call letter, if known).
(fc) To break or stop the signals from the sending station. — Make the signal QUT
front.
(c) To start the sending station after breaking. — Make the interrogatory signal
followed by the last word received correctly. The sender will then resume his message,
beginning with the word indicated by the receiver.
(rf) To acknowledge the receipt of a message — Signal R front followed by the
name or call letter of the receiver.
Each word, abbreviation, or conventional sign is followed by front.
To lessen the liability of error, numerals which occur in the body of a message
must be spelled out in full.
CONVENTIONAL SIGNALS.
End of word front. Repeat last message .... Interrogatory
End of sentence front, front. three times.
End of message. . . .front, front, front. Move to your right MR front.
Error AA front. Move to your left M.L. front.
Interrogatory - Move up MTT front.
Acknowledgment, Move down MD front.
or I understand R front Use your other flag UF front.
Cease signalling- QRT front. Signal faster QRQ. front
Wait a moment - Signal slower QRS front.
Repeat after (word) ... .Interrogatory Finished (end of work) .. -
(word).
Section 126— Wigwag Codes
Any of the codes previously described for the heliograph are equally applicable
to flag or wigwag signalling. The " 1 " of the Myer code is made by a motion to the
right, the dot of the International Morse code. The "2 " is a similar motion to the
left, The front is the " 3."
In using the Alphabetical 'Square code, the number of motions to the right will
indicate the first figure of each symbol while those to the left indicate the second
figure of the symbols. The front may be used as with the other codes. This code
is best adapted to small flags and short ranges, where the motions may be very rapid.
Section 127 — Semaphore Signalling
1 — WITH FLAGS
In this system the letters depend OTI the position of one or both arms in relation
to the body. A point midway between the shoulders may be taken as the centre of a
circle, where the arms may be considered as being pivoted so that a complete circle
may be described by them. This method is rapid but useful only for distances of
2 miles or less, and requires two flags. It is, therefore, not so well adapted for forest
communication as is the wigwag. The semaphore alphabet is shown in Fig. 111.
2 — WITH FIXED SEMAPHORE
An interesting application of the semaphore method may be made with a large
fixed-semaphore apparatus. This consists of a vertical staff or pole to which are
pivoted the signal arms. The pole should be high enough so that it is not obscured
192
METHODS OF COMMUNICATION FOR FOREST PROTECTION
by nearby objects. It may be erected on the roof of a cabin and operated from inside
if desired, or if placed on top of a tower it may be operated from the ground. The
arms are flat boards which must be at least 3 ft. long, and these must increase 1 ft.
in length for each mile over 3 miles at which the semaphore is to be read. As 10-ft
Fig-. Ill The semaphore alphabet, numerals, and special signs
arms would probably be about the maximum size that could be erected and manipu-
lated at a forest patrol or lookout station, the range would be limited to 10 miles.
The width of the arms should be one-sixth of the length. The arms are moved by
a system of levers, ropes, and pulleys. The levers are placed at or near the base of
the pole bearing the arms and may reproduce the position of the arms themselves.
If the semaphore is to be read from only one direction, the apparatus should be fixed
so that the arms move in a plane at right angles to the line connecting the two
stations. If it must be read from various directions, it is necessary to place the
arms on a revolving shell or casing surrounding the fixed pole and1 provided with
roller bearings >at the base; or the supporting pole may be set on a ball-and-socket
joint to permit of rotation. For signalling by the semaphore method, only two arms
are required and these are fixed on the same pivot near the top of the upright pole.
The letters are made by the position of these two arms just as when using flags held
in the hands. In addition to the two movable arms it is necessary to have a third
shorter fixed arm called the "indicator." This arm is placed on the right of the
sender, the left as viewed by the receiver. The code is the same as used with hand
flags and is illustrated in Fig. 112.
USING THE FLAG 193
To signal with the Morse code four arms and the indicator are required. An
arm placed at an angle of 45° to the upright post forms a dot of the code; one placed
horizontally or at an angle of 90° forms a dash. The signals are read from the top
down. The front or "3" of the Myer or Wigwag code is made by dropping all arms
to the vertical position. Although limited in range and, except in the smaller sizes,
slow to operate, this apparatus may sometimes be found useful on lookout stations',
especially those equipped with towers and read from only one direction. The con-
ANNULLING
NTERRQGAT
.TTENTlON
O
SIGNALS
(FOLLOW)
NEGATIVE PREPARATOR
ACKNOWLEDGE
LETTERS
NTERVAL
Pig. 112 Two-arm, fixed semaphore code
struction is simple and the signals more easily read than the flag at a similar dis-
tance. Code messages are readily set on a fixed semaphore and kept displayed for
long periods. In fact, this is by far the most useful application of the fixed sema-
phore to forest protection, and, as about 650 code messages can be sent using one
and two letters only, by building a semaphore with two sets of movable arms on a
lookout peak any one of the 650. messages may be set on the semaphore and left dis-
played to the view of the entire protection staff within range of the station. The
arms should be painted according to the colour of the background against which
they are displayed. Yellow or orange with a red strip will generally be found mrst
effective.
79211—13
CHAPTER XXIV
MESSAGE CODES
Section 128 — Purpose of Codes
Message codes are devised in order that preconcerted phrases or sentences may
be expeditiously transmitted. They are widely employed in various lines of activity
•and can be made extremely useful in forest-protection communication, especially
where methods of communication other than the telephone are relied upon and the
operators have had only limited training. In these codes, one, two, or three letters
of the alphabet are used to designate each prearranged sentence, and' by having a
well arranged copy of the code at each station it is possible to send and receive whole
sentences or messages in the time needed to transmit only these one, two, or three
letters.
Section 129— Use in Forest Protection
A message code is particularly adaptable to forest fire detection work. The first
code used in forest protection was- employed by the author, with lookout stations
equipped with heliographs, in 1909. Others have since been devised, the latest being
that of the United States Forest Service in District 1, issued in May, 1916. To a
certain extent it is necessary to devise a code to fit the conditions of operation, and
the main problem lies in anticipating the messages that it will be necessary for the
operator to send. Thus far, mesisage codes have been employed only for the sending
of messages from lookout stations. A code of this sort is given in the " Dominion
Forestry Branch Message Code" (see note below). This code will be employed for
signal communication on Dominion forest reserves wherever signal equipment is
installed. If it is found necessa-ry to alter or extend it to fit local conditions this
may readily be done by following the rules for preparation given in the " Dominion
Forestry Branch Message Code."
/
Section 130 — Combinations Available
With two letters of the alphabet in each signal and with no repetition of a letter
in any display, 624 combinations are possible, and each may represent a prearranged
phrase, sentence, or message. By using the single letters of the alphabet and also
such combinations as A A, B B, etc. 52 additional signals may be obtained, making
676 in all. From these, however, it will be advisable to eliminate the various letters
and combinations usecfr as conventional signals in the International and other codes,
but there will still remain well over 650 available combinations.
Six hundred and fifty phrases give a range of possibilities that covers rather
fully the urgent messages that need to be sent by one lookout man to another, or to
headquarters, and the saving in time is apparent when it is considered for instance
that by sending simply two code letters the lookout man may be enabled to transmit
such a message as : "I have sighted a fire, the azimuth bearing of which from my
station is 24 degrees."
If 650 signals are not sufficient, by using combinations of three letters in addi-
tion to those composed of one and two, more than 16,000 different signals are made
available.
]\T0fp — The preceding sections deal with codes in general, their purpose and
scope. The particular code prepared for the use of the officers of the Dominion
Forpstrii Branch is, for convenience, published in the form of a small, separate book
entitled "Dominion Forestry Branch Message Code."
194
CHAPTER XXV
DANGER SIGNALS
Section 131 — Risk in Fire-fighting
Fighting forest fires in heavy timber is a work attended' with considerable hazard.
Injuries caused by falling trees are frequent, but loss of life is generally due to
crews being cut off by fires of the existence of which in their near vicinity they were
unaware; or by the sudden development of dangerous conditions in the fire they are
themselves fighting, due to high winds or other causes. Nearly 100 men were thus
burned or suffocated in the National Forests of Northern Idaho in 1910. Loss of
life among fire-fighters has occurred to a certain extent in nearly every region where
an aggressive effort is being made to protect the forests from this enemy. This is,
of course, in addition to the loss of lives among settlers and inhabitants of forest
communities in regions where forest protection staffs either do not exist or have not
the organization and efficiency required to protect the community and confine losses
to the active field forces who must necessarily take certain risks.
Section 132 — Use of Danger Signals
In order to guard fire-line crews as much as possible from the risk attendant upon
the sudden development of dangerous conditions several protective organizations
have considered it advisable to adopt a simple code of danger signals to be used only
in case of great emergency on the fire-line. Such signals must be easily made with
equipment that can be available at all times, and must be of such a character that
they can be conveyed simultaneously to all the men working on a fire-line of the
usual length. To avoid any chance of signals being given improperly or by un-
authorized persons, it is preferable to have them made by some instrument not likely
to be in the possession of such persons. The signals that best meet these require-
ments are revolver shots or whistle blasts. The' distance over which shots may be
heard in the woods varies with the wind direction, the size of the cartridge, the inter-
vening topography, and the outside noises. In ordinary timber on level ground, with
no wind or unusual noises, the report of a -3'S-calibre revolver may be heard at a
distance of | to 1 mile. Whistle blasts vary with the kind of whistle employed and
also with the wind, topography, and outside noises. The type known as a two-tone
police whistle may be heard under the conditions described above at a distance of 200
yards.
Signals of this kind are useful, of course, only to the actual fire-fighting forces.
Where, as is usually the case, the forest-protection staff also has the duty of providing
for the safety of forest communities, the general forest intercommunication system
and the discipline of the staff itself must be relied upon to safeguard these interests.
Section 133 — Code of Danger Signals
The following code of danger signals has been adopted by the forest officers in
the National Forests of the State of California and will also be employed by officers
of the Dominion Forestry Branch. All men going on the fire-line should be instructed
in these signals and the officer in charge of the fire will carry a revolver or automatic
pistol or a suitable whistle.
- (A series of any number of single shots or short whistle blasts with
intervals of not less than two seconds between each)=" The fire is in a dangerous
condition.- Escape by running down hill."
79211— 13i
195
196 METHODS OF COMMUNICATION FOR FOREST PROTECTION
(A series of any number of double shots or double whistle blasts with
intervals of not less than two seconds between each pair)=" The fire is in a dangerous
condition. Escape by running up hill"
(A series of more than two single shots, generally the gun-fall or discharges
as close together as possible.)
or
— (A series of more than two long whistle blasts with intervals of not
less than 4 seconds between each, repeated until a response is received) =" Assemble
at this point."
Section 134 — Miscellaneous Uses of Shot and Whistle Signals
The usefulness of shot and whistle-blast signals is not, however, confined to
warnings on fire-lines, although in the vicinity of fires they should be used for no
other purpose, in order to avoid any chance of confusion. Both, however, may be
used to advantage by survey parties, cruisers, packers, and others. In hunting strayed
horses, for instance, it often saves much inconvenience and loss of time if the man
who first locates the stock conveys news of the fact to the others engaged in the hunt
by shots or whistle blasts. Many other cases are constantly arising in forest work
where such signals may be used to very great advantage and with much gain in
efficiency. A striking example is in the work of " pulling wire " when building tele-
phone lines, and in u pulling slack " on tree lines. A simple code of shot signals
should always be arranged by wire-pulling crews so that the man watching the reel
can signal the pulling crew to stop, start, or come back, as may be necessary.
It is in fact the duty of every leader of a party in the woods to study the con-
ditions under which his men are working and to devise a simple code of audible
signals by which they may communicate with each other, using as the signal-pro-
ducing mechanism the handiest equipment in the outfit. Under most conditions this
will be a six-shooter or an automatic pistol.
APPENDIX A
OUTFIT FOE TELEPHONE CONSTRUCTION CREW
The tools and supplies required for the construction of a telephone line will vary
somewhat according to whether a tree line or a pole line is to be built. The size of
the crew will probably vary also. In the following lists, however, a ten-man crew
including foreman, cook, and teamster has been taken as the basis for the calcula-
tions. Provision is made for having all the tools that may reasonably be needed on
the job. Makeshift substitutes or special trips for tools not provided at the proper
time cost much more than the transportation of a few extra tools.
1 — TEN-MAN CREW FOR TELEPHONE CONSTRUCTION
Pole Line — . Tree Line —
1 foreman. 1 foreman.
1 cook. 1 cook.
1 teamster or packer. 1 teamster or packer.
4 linemen (some of the linemen will have 3 linemen (some of the linemen may have
to assist in digging holes and setting to be employed part of the time in clear-
poles part of the time). ing right of way).
2 groundmen. 3 groundmen.
1 utility man. 1 utility man.
APPENDIX A— OUTFIT FOR CONSTRUCTION CREW
197
2 — LIST OF LINE SUPPLIES
(Material per mile of Standard Grounded Circuit)
(a) Pole Line —
30 poles, 22^ or 25 feet.
320 pounds No. 9 B.W.G., B.B. galvanized-
iron telephone wire.
30 12-inch painted oak brackets.
30 regular pony, long-distance, glass in-
sulators.
4-inch and 30 6-inch galvanized wire
30
nails.
30 2-inch fence-staples.
Approximate total weight, 7,900 pounds.
(b) Tree Line —
315 pounds No. 9 B.W.G., B.B. galvanized-
iron telephone wire.
55 standard, porcelain, split tree insulators.
55 4 -inch or 3 -inch iron staples.
5 pounds No. 12 B.W.G., B.B., galvanized-
iron telephone wire.
Approximate total weight, 350 pounds.
NOTE. — Additional materials must be provided for braces, guys, and special construction,
if any, according to the conditions in each individual case.
3 — LIST OF STATION SUPPLIES
(Material required per Station)
(a) Standard Indoor Installation —
(For trade description of supplies see List
of Standard Equipment, Section 44.)
1 1317-S type telephone set.
3 dry cells.
40 ft. No. 14 B. & S. gauge, rubber-covered.
weather-proof, copper wire.
10 ft. No. 19 B. & S. gauge, rubber-covered
weather-proof copper wire.
1 standard protector.
2 standard protector micas.
4 standard protector blocks.
1 7-ft. standard, galvanized-iron ground rod.
1 12 -inch oak bracket.
1 standard glass insulator.
6 No. 4£ porcelain knobs.
6 3-inch flat-head wood screws.
2 porcelain tubes. 6 by 1 by i%e inches.
5 IJ-inch blued, round-head screws.
20 i-inch Blake insulated staples.
2 7 -ampere tubular line fuses (required only
with 58-F type protector).
1 asbestos protector mat (required only with
58-F type protector).
2 ft. brass oilcloth binding.
, 1 howler (required only for receiving vibra-
tory signals).
1 condenser (required only for receiving
vibratory signals).
Approximate total weight, 50 pounds.
(5) Standard Outdoor Installation —
1 1336-J type telephone Set.
4 3 -inch galvanized-iron lag screws.
2 wooden cleats, 3 by 4 by 18 inches.
8 6-inch wire nails.
1 protector mounting-box.
1 60-E type protector.
4 standard protector blocks.
2 standard protector micas
1 S.P.S.T. baby knife-switch.
5 2-inch blued, round-head screws.
30 feet No. 14 B. & S. gauge, rubber-covered,
braided and weather-proofed, copper wire.
1 7-ft. galvanized-iron ground rod.
30 2 -inch Blake insulated staples.
2 dry cells.
Approximate total weight, 115 pounds.
4 — LIST OF CONSTRUCTION TOOLS
(a) Pole-line Construction —
7 long-handled, round-pointed shovels.
5 7-ft. digging spoons.
1 standard tree-trimmer.
5 combined digging and tamping bars.
1 standard post-hole auger.
3 double-bitted axes with handles.
1 brush-burning torch (where needed).
4 reversible splicing clamps.
5 8-inch linemen's pliers.
4 pairs eastern climbers with pads and
straps.
4 linemen's belts Tvith safety straps.
5 hand-axes, Hudson Bay pattern.
2 Buffalo grips with pulleys.
1 Haven clamp.
1 3-inch double pulley block (with one hook).
1 3 -inch double 'pulley block (with hook and
eye.)
35 ft. 1-inch sash cord.
35 ft. 1-inch sash cord.
1 wire-reel.
1 pole support (for poles 35 feet and over,
only).
4 pike-poles (for poles 30 feet and over, only).
1 12-inch monkey wrench.
(a) Pole-line Construction — Con.
1 carborundum grinder.
2 double-bitted axe-handles.
1 brace and P-inch bit (12-inch twist. 6-inch
shank).
3 carborundum whetstones. 4 -inch.
6 10-inch flat files.
1-12-inch wood rasp.
Approximate total weight, 380 pounds.
(&) Tree-line Construction —
(When an occasional pole will have to be
set on a tree line, sufficient pole-setting
tools to handle the work must be included
in the outfit.)
8 double-bitted axes with handles.
1 cross-cut saw (2-man).
2 steel felling wedges.
1 peavy.
1 brush-burning torch.
3 reversible splicing clamps.
4 8-inch linemen's pliers.
3 Eastern climbers with pads and straps.
3 linemen's belts with safety straps.
4 hand-axes, Hudson Bay pattern.
3 standard tree-trimmers.
198
METHODS OF COMMUNICATION FOR FOREST PROTECTION
4 — LIST OF CONSTRUCTION TOOLS. — Continued.
(&) Tree-line Construction — Oon.
1 wire-reel.
1 carborundum grinder.
6 carborundum whetstones. 4 -inch.
12 10-inch flat files.
12 8 -inch flat files.
1 saw-filing and saw-setting- outfit.
1 12-inch wood rasp.
4 double-bitted axe-handles.
Approximate total weight, 185 pounds.
(c) Emergency -line Construction —
(The requirements vary according to the type
of construction attempted. This list is
the maximum for a line hung on trees or
bush, and in a pinch most of these tools
can be omitted.)
1 pair 6-inch side-cutting pliers.
1 emergency wire-reel.
2 hand-axes.
1 crook-stick.
1 roll friction tape.
(c) Emergency-line Conctruction — 'Con.
1 ball cotton twine.
60 3-inch nails.
1 pair climbers.
Approximate total weight, 17 pounds.
(d) Station Installation —
1 carpenters' hammer.
1 8 -inch screw-driver.
1 4 -inch screw-driver.
1 brace and n/ie-inch bit (12-inch twist. 6-
inch shank).
1 gasolene blow-torch.
1 quart gasolene.
1 soldering copper.
1 pound resin-core solder.
1 roll friction tare.
1 pair 5-inch oblique, side-cutting pliers.
1 pair 6-inch long-nosed pliers.
1 monkey-wrench.
1 knife, electricians'.
Approximate total weight, 16 pounds.
5 — LIST OF TENTAGE
1 12-by-14-ft. wall tent with fly (cook tent).
1 12-by-14-ft. wall tent with fly (mess tent).
3 7-by-9-ft. wall tents (sleeping tents).
Approximate total weight, 350 pounds.
6 — LIST OF PROVISIONS
(Ten men for ten days — 100 rations)
Flour, 100 pounds.
Cured meats, 75 pounds (if fresh meat is
available, use 50 pounds cured, 25 pounds
fresh).
Potatoes, lO'O pounds.
Beans, 20 pounds.
Sugar, 40 pounds (if syrup is preferred, re-
duce sugar accordingly).
Lard, in 5-pound pails, 10 pounds (if fresh
meat is used increase lard to 15 pounds)
Graham flour. 5 pounds.
Pancake flour. 6 pounds.
Salt, 3 pounds.
Baking powder. 3 pounds.
Soda, 1 pound.
Yeast cake, 1 packet.
Butter, creamery, 1-pound cartons, 10
pounds.
Dried fruits, 20 pounds.
Rice, 5 pounds.
Coffee, ground, good grade, 1-pound sealed
tins, 10 pounds.
Tea, 1 pound.
Cocoa, i -pound cans, 2 pounds.
Cheese, 5 pounds.
Milk, carnation grade, 48 cans.
Macaroni, 2 pounds.
Corned-beef, 2-pound cans, 5 cans.
Tomatoes, 2J-pound cans, solid pack, 8 cans.
Peas, 2-pound cans, solid pack, 5 cans.
Corn, 1-pound cans, solid pack, 10 cans.
Sauerkraut, 3 pounds.
Rolled oats, 10 pounds.
Cornmeal, 5 pounds.
Eggs, 10 dozen.
Ketchup, 2 bottles.
Pickles, sour, 1 kit (or 2 gallons).
Mustard, ground, 4-oz. can.
Pepper, ground, 8-oz. can.
Cinnamon, ground, 4-oz. can.
Allspice, ground, 4-oz. can.
Lemon extract. 4-oz. bottle.
Vanilla extract, 4-oz. bottle.
Vinegar, 1-quart bottle.
Soap, laundry. 5 pounds.
Matches, 3 small packages.
Candles, 2 pounds.
Coal oil. 1 gallon.
Chloride of lime, |-pound cans, 4 cans.
Onions, 10 pounds.
Approximate total weight, 550 pounds.
7 — LIST OF KITCHEN EQUIPMENT
(Crew of 10 men, including foreman and cook)
1 granite coffee-pot, 8 -quart.
1 granite tea-pot, 3 -quart.
1 lantern.
2 single-bitted axes.
1 sheet-steel cook-stove. No. 8, with 6 joints 2 dishpans, 14-quart.
of pipe.
4 frying pans, assorted sizes.
2 granite kettles, 12-quart, with covers.
4 granite kettles, 6-quart with covers.
2 granite stew-kettles, 6-quart, with covers.
1 granite rice-boiler, 6-inch.
2 dripping-pans to fit oven of stove.
1 can opener.
1 rolling pin.
4 tin wash basins.
APPENDIX SI— USEFUL BOOKS OF REFERENCE 199
7 — LIST OF KITCHEN EQUIPMENT. — Continued.
4 tin water-pails, 10-quart. 5 yards 12-ounce duck or light canvas, 36-
3 tin dippers, 1-quart. inches wide (this item is intended to be
11 dozen retinned plates. used for tops for table frames built of
1* dozen retinned cups and saucers. light poles. Narrow strips of wood, like
\ dozen retinned dish-up basins. 2-quart. lath, 36-inches long, should be tacked to
i dozen retinned dish-up basins, 1-quart. the canvas 1-inch apart. The cover thus
1 dozen porridge bowls. made can be kept clean quite easily and
1 retinned syrup pitcher, 1-quart. may be rolled up into a compact bundle
1 retinned cream pitcher, 1-quart. and readily packed from one camp to an-
2 butcher knives, one 10-inch, one 12-inch. other. Two covers are provided — for
1 butchers' steel. mess table 9 feet long and for cook's
1 meat fork. table 6 feet long).
2 retinned stirring spoons. ^ pound 10 -ounce tacks.
1 meat saw. 10 pounds assorted nails.
4 tin milk pans, 5-quart. 1 carpenters' hammer.
\\ dozen wood-handled, steel knives and 1 carpenters' hand-saw.
forks. 1 alarm clock.
1'J dozen tea-spoons. 10 yards unbleached muslin.
li doz?n table-spoons. 10 yards crash towelling.
1 5-gallon can, galvanized iron. Approximate total weight, 325 pounds.
NOTE. — The lists of tents, provisions, and kitchen outfit are taken from ''Trail Construction
on the National Forests," issued by the United States Forest Service.
APPENDIX B
USEFUL BOOKS OF REFERENCE
1 — SCIENCE OF TELEPHONY
" American Telephone Practice " by Kempster B. Miller, published by McGraw-
Hill Book Co., 239 West Thirty-ninth St., New York City, U.S.A.— price, $4.
"Practical Telephone and Guide to Telephone Exchange" by T. S. Baldwin,
published by Frederick J. Drake & Co., 1328 South Michigan Boulevard, Chicago,
111., U.S.A.— price, $1.
*"A.B.C. of the Telephone" by James E. Homans, published by Theo. Audel
& Co., 72 Fifth Ave., New York City, U.S.A.— price $1.
" Telephone Engineering " by James E. Homans, published by Theo. Audel & Co.,
72 Fifth Ave., New York City, U.S.A.— price, $1.
" Modern American Telephony " by A. B. Smith, published by Fred J. Drake &
Co., Chicago, 111., U.S.A.— price, $2.
2 — LINE CONSTRUCTION
*" How to Build Rural Telephone Lines," issued by the Northern Electric Co.,
Montreal, Quebec — price, 50 cents.
" Telephone Construction and Maintenance on the National Forests," issued by
the United States Forest Service, sold by the Superintendent of Documents, Wash-
ington, D.C., U.S.A. — price 15 cents.
" Telephone Construction Methods and Cost " by Clarence Mayer, published by
Myron C. Clark Pub'g Co., 527 South Dearborn St., Chicago, 111.— price, $3.
" Electrical Instruments and Telephones of the Signal Corps," issued by the
United States Army Signal Corps, sold1 by the Superintendent of Documents, Wash-
ington, D.C., U.S.A. — price, 65 cents.
" Instruction in Army Telegraphy and Telephony," Vol. II, issued by the General
Staff, War Office, 'Great Britain, obtainable from the Department of Militia and
Defence, Ottawa — price, 50 cents.
200 METHODS OF COMMUNICATION FOR FOREST PROTECTION
3 — PREPARATION AND PRESERVATION OF POLES
The following books have been issued by the United States Forest Service, aiiu
may be procured from the Superintendent of Documents, Washington, D.C., U.S.A.,
at the prices indicated: —
" Prolonging the Life of Telephone Poles " (reprint from the Year Book of the
United States Dept. of Agriculture, 1905) — price, 5 cents.
" Seasoning of Telephone and! Telegraph Poles," United States Forest Service
Circular 103 — price, 5 cents.
" Brush and Tank Pole Treatment," United States Forest Service Circular 104—
price, 10 cents.
" Test of Eocky Mountain Woods for Telephone Poles " — price, 5 cents.
" Preservative Treatment of Poles," United States Forest Service Bulletin 84—
price, 15 cents.
4 — MILITARY SIGNALLING AND TELEPHONY
*" Training Manual — Signalling" (provisional 1915), issued by the General Staff,
War Office, Great Britain; obtainable from the Department of Militia and Defence,
Ottawa — price, 25 cents.
" Signalling " by E. J. Solano, published by John Murray, Albemarle 'St., London,
W., England — price, 25 cents.
*" Manual of Visual Signalling, 1906," issued by the 'Signal Corps, United States
Army, sold by the Superintendent of Documents, Washington, D.C., U.'S.A. — price,
35 cents.
*" Electrical Instruments and Telephones of the United States 'Signal Corps,"
sold by the Superintendent of Documents, Washington, D.C., U.S.A. — price, 65 cents.
" Instructions in Army Telegraphy and Telephony," Vol. 1, by the General
Staff, War Office, Great Britain, obtainable from the Department of Militia and
Defence, Ottawa— price, 50 cents.
*" Field Telephones for Army Use" by E. J. Stevens, published by Crosby,
Lockwood & 'Sons, London, England — price, $1.
*" Field Equipment for Signal Troops," issued by the Signal Corps, United States
Army, obtainable from the Army Signal School, Fort Leavenworth, Kansas, U.S.A. —
price, 25 cents.
" The Buzzer and Other Devices for Induction Telegraphy," issued by and obtain-
able from the same authorities as the preceding — price, 25 cents.
*" Signal Book, United States 'Army " 1916, sold by the Superintendent of Docu-
ments, Washington, D.C., U.'S.A. — price, 20 cents.
5 — TELEPHONE TROUBLES
*Hyde's " Telephone Troubles and How to Find Them," published' by W. H. Hyde
& Co., Milwaukee, Wisconsin, U.S.A. — price, 25 cents.
NOTE. — 'Most of the books on Telephone 'Science and Line Construction listed
herein contain chapters on the location and clearing of trouble.
6 — SPECIALIZED FIRE PROTECTION
*" Fire Protection in District ~N~o. 1— Misc. Pub. 0-7," issued by the United States
Forest Service, sold by the 'Superintendent of Documents, Washington, D.C., U.S.A. —
price, 15 cents.
*" National Forest Fire Protection Plans," issued by the United 'States Forest
Service, sold by the Superintendent of Documents, Washington, D.C., U.'S.A.- — price,
'IB cents.
APPENDIX C— TELEPHONE COSTS, 201
7 — PERIODICALS
" Telephony " (weekly) published by Telephony Publishing Co., 341 Monadnock
Block, Chicago, 111., U.'S.A. — price, $3 per year.
" Western Electric 'News " (monthly) published by the Western Electric Co.,
(company organ).
3 — TMADE CATALOGUES AND HANDBOOKS
" Handbook of Insulated Wires and Cables " issued by Phillips Insulated Wire
Co., Pawtucket, R.I., U.S.A.
" The Simplex Manual " issued by the 'Simplex Wire and Cable Co., 201 Devon-
shire St., Boston, Mass., U.S.A.
*" Wire in Electrical Construction ' 'issued by John A. Roebling's Sons Co..
Trenton, N J., U.S.A.
" Electrical Wires and Cables " issued by the American 'Steel & Wire Co., Montreal,
Quebec.
" Northern Electric Telephone Apparatus and Supplies, Catalogue No. 3 " issued
by the Northern Electric Co., Montreal, Quebec.
(*) The books and government documents marked with this symbol will be found
particularly suited to those who have made no previous study of telephone science but
desire to secure some elementary knowledge of the instruments and of signalling
methods in general, with the use that may be made of rapid means of communication
in forest protection.
A great deal of useful information may be secured from the trade catalogues
issued by the various manufacturers of telephones and telephone supplies and also by
the manufacturers of iron and copper wire. These will always he furnished gladly on
application, are nearly always profusely illustrated, and often contain much valuable
data that is available nowhere else.
APPENDIX C
TELEPHONE COSTS
1 — FACTORS INVOLVED IN THE ESTIMATION OF COSTS OF POLE AND TREE TELEPHONE LINES
The cost of forest-protection telephone lines depends upon so many variable
factors that general statements are of very little value. Particularly is this true since
the beginning of the European War. Materials and equipment have increased enor-
mously in price, some have even become unobtainable and great delays in delivery must
be expected in nearly all supplies. Labour has also both increased in price and to a
certain extent decreased in quality. As in other construction work, estimates of
supplies1 must be based on quotations and freight rates to point of delivery. Esti-
mates of transportation away from railways must be based on daily cost of transport
equipment, a»verage load, and average daily trip. Estimates of labour must be based
on daily wage scale with proper allowance for board, and a knowledge of what con-
stitutes a reasonable day's task under the existing conditions that to a certain extent
differ with each project. This can only be done properly 'by a study of conditions
along the proposed route, coupled with an accurate knowledge of actual costs on
similar projects. Classified project costs are being accumulated by the Forestry
Branch but as yet are not available for the general information of the field staff.
202
METHODS OF COMMUNICATION FOR FOREST PROTECTION
In preparing an estimate for a telephone line, the costs should be classified under
the heads shown in the following schedule: —
Estimating Cost of Pole Lines —
(a) Survey of route.
(&) Tools.
(c) Line materials.
(1) Wire.
(2) Insulators, brackets, and nails.
(3) Poles.
(4) Guys, braces and miscellaneous.
(d) Station materials.
(e) Transportation.
(1) Wire and miscellaneous supplies.
(2) Poles.
(3) Camp moving.
(/) Line clearing:.
(1) Cutting.
(2) Burning.
(g) Line construction.
(1) Digging holes.
(2) Setting poles.
(3) Pulling 'wire.
(4) Tying in.
(5) Miscellaneous adjustments, guys, etc.
(ft) Station installations.
(1) Outside work.
(2) Inside work.
2 — Estimating Costs of Tree Lines —
(a) Survey of route.
(&) Spotting trees.
(c) Tools.
(d) Line materials.
(1) Wire.
(2) Insulators and staples.
(3) Miscellaneous and poles (if any),
(e) Station materials.
(/) Transportation.
(1) Wire and insulators.
(2) Camp moving.
(g) Line clearing.
(1) Cutting.
( 2 ) Burning.
(h) Line construction.
(1) Pulling wire.
(2) Tying in.
(3) Pulling slack.
(4) Setting poles (if any).
(i) Station installation.
(1) Outside work.
(2) Inside work.
2— APPROXIMATE COSTS OF SUPPLIES AND AVERAGE TIME REQUIRED FOR VARIOUS OPERA-
TIONS IN TELEPHONE LINE CONSTRUCTION
'All figures based on quotations in Prairie Provinces prior to the European War)
1 — Supplies —
(a) Tools (per ten-man crew).
(1) For pole line, $200.
(2) For tree line, $120.
(3) For station work, $25.
(&) Line materials (per mile).
(1) Wire, No. 9 B.W.G., $12.
(2) Insulators, etc., $2.
(3) Poles, 25 feet, $18 up.
(4) Miscellaneous, $1 up.
(c) Station materials each, $15.
2 — Transportation —
This is a cost that depends so much on local
condition that no average figure has any
value. The weight to be transported
may be determined from -the lists in
Appendix A.
3 — Spotting Trees —
(a) Very open timber — 2 men, 2 miles per
hour.
(&) Very dense timber — 3 men, i mile per
hour.
4 — Line Clearing —
This is a cost that depends entirely on local
conditions. In general, right of way for
tree lines should seldom cost over $25 per
mile for clearing, with labour at 30 cents
per hour, but under exceptionally un-
favourable conditions may run to $45 per
mile. In fair-sized timber with little
underbrush the cost may be as low as $2
per mile. For pole lines the cost will be
materially higher, depending on the
width of clearing.
5 — Line Construction, Tree lines —
(a) Pulling wire.
(1) Best — 2 men and 1 horse, 1 mile
per hour.
(2) Worst — 5 men, J mile per hour.
(6) Tying in.
(1) Best — 1$ miles per man, per day.
(2) Worst — \ mile per man, per day.
(c) Pulling slack — 2 men, 1 mile per hour.
On pole lines all these costs will be reduced
from 15 to 50 per cent.
6 — Erecting Poles, 2>2J or 2>5 feet —
(a) Digging holes.
(1) Soft ground — 1 man, 3 holes per
hour.
(2) Medium ground — 1 man, 1'hole per
hour.
(3) Hard ground — 1 man, § hole per
hour.
(&) Setting poles — 3 men, 2J poles per hour,
(c) Attaching lightning-rods — 1 man, 4 rods
per hour.
(d) Guying and anchoring — 2 men, 2 an-
chors per day.
7 — Station Installation —
(a) Best — 1 man, 3 hours (indoor).
2 men, 2 hours (outdoor).
(&) Worst — 1 man, 5 hours (indoor).
2 men, 4 hours (outdoor).
APPENDIX D
REGULATIONS OF THE BOARD OF RAILWAY COMMISSIONERS FOR
CANADA REGARDING WIRE CROSSINGS
No. 10 — WIRES ERECTED ALONG OR ACROSS RAILWAYS
By section 7 of chapter 22, 1-2 George V (1911), section 4 of chapter 50 of the
Statutes of 1910 was repealed, and the following was enacted as subsection 5 of section
246 of the Railway Act:—
" 5 An order of the Board shall not be required in cases in which wires or other
conductors for the transmission of electrical energy are to be erected or maintained
over or under a railway, or over or under wires or other conductors for the transmission
of electrical energy with the consent of the railway company or the company
owning or controlling such last-mentioned wires or conductors in accordance with any
general regulations, plans, or specifications adopted or approved by the Board for such
purposes."
NOTE. — The above applies to construction across the railway only. Where the
wires or other conductors are to be erected along the railway, an order of the Board
is necessary.
General Order No. 231 of the Board of Railway Commissioners
In the matter of section 21+6 of the Railway Act, as amended l>y chapter 37 of the
Acts 7-8 George V, section 4, for the carrying of wires and cables along or
across the tracks of railway companies under the jurisdiction of the Board.
Upon the report and recommendation of the Electrical Engineer of the Board, —
It is ordered: —
1 That the conditions and specifications set forth in the schedule hereto annexed,
under the heading, " Rules for Wires erected along or across Railways," be, and the
same are hereby, adopted and confirmed as the conditions and specifications applicable
to the erection, placing, or maintaining of electric lines, wires, or cables along or
across all railways subject to the jurisdiction of the Board, part 1 being applicable
where the line or lines, wire or wires, cable or cables, is or are carried along or over
the railway; part 2 being applicable where the line or lines, wire or wires, cable or
cables, is or are carried under the railway.
2 That any order of the Board granting leave to erect, place, or maintain any
line or lines, wire or wires, cable or cables, along or across the railway and referring
to " Rules for Wires erected along or across Railways," shall be deemed as intended
to be a reference to the conditions and! specifications set out in that part of the said
schedule which is applicable to the mode of crossing authorized.
3 That any order of the Board granting leave to erect, place, or maintain any
line or lines, wire or wires, cable or cables, along or across any railway subject to the
jurisdiction of the Board, shall, unless otherwise expressed, be deemed to be an order
for leave to erect, place, and maintain the same according to the conditions and specifi-
cations set out in that part of the said schedule applicable thereto, which conditions
and specifications shall be considered as embodied in any such order without specific
reference thereto, subject, however, to such change or variation therein or thereof as
shall be expressed in such order.
203
204 METHODS OF COMMUNICATION FOR FOREST PROTECTION
4 That the general order of the Board No. 113, dated November 5, 1913, approv-
ing of " Rules for wires crossing railways," and the conditions and specifications
adopted thereby, be, and the same is hereby, rescinded.
H. L. DRAYTON,
May 6, 1918. Chief Commissioner.
Schedule
NOTICE TO APPLICANTS
"When the interested company's consent cannot be procured and an application to
the Board becomes necessary, send to the Secretary of the Board (postage free) with
the application, three copies of a sketch or drawing about 8 by 10 in. showing: —
(a) The location of the poles or towers, or the location of the underground con-
duit in relation to the track; the dimensions of the poles or towers; and the material
or materials of which they are made.
(fe) The proposed number of wires, or cables, the distance between them and the
track and the method of attaching the conductors to the insulators.
(c) The location of all other wires adjacent or to be crossed, and their supports.
(d) The maximum potential, in volts, between wires, the potential between wires
and the ground, and the maximum current, in amperes, to be transmitted.
(e) The kinds and sizes of the wires or conductors in question.
(/) On circuits of 10,000 volts, or over, the method of protecting the conductors
from arcs at the insulators.
(#) The number of insulators supporting the conductors. (See also " J" in
Specifications.)
N.B. — Place a distinguishing name, number, date, and signature upon the draw-
ing. Mark the exact location of the lines or wires upon the drawing, by stating the
distance in miles from the nearest railway station — N., E., S. or W. — so that this
point can readily be identified.
STANDARD CONDITIONS AND SPECIFICATIONS FOR WIRE CROSSINGS
PART I — OVER-CROSSINGS
Conditions
1 The applicant shall, at its or his own expense, erect and place the lines, wires,
cables, or conductors authorized to be placed along or across the said railway, and shall
at all times, at its own expense, maintain the same in good order and condition and at
the height shown on the drawing, and in accordance with the specifications hereinafter
set forth, so that at no time shall any damage be caused to the company owning, operat-
ing or using the said railway, or to any person lawfully upon or using the same, and
shall use all necessary and proper care and means to prevent any such lines, wires
cables, or conductors from sagging below the said height.
2 The applicant shall at all times wholly indemnify the company owning, operat-
ing, or using the said railway, of, from, and against all loss, cost, damage, and expense
to which the said railway company may be put by reason of any damage or injury to
persons or property caused by any of the said wires or cables or any works or appli-
ances herein provided for not being erected in all respects in compliance with the
terms and provisions of this order, as well as any damage or injury resulting from the
imprudence, neglect, or want of skill of the employees or agents of the applicant.
3 No work shall at any time be done under the authority of this order in such a
manner as to obstruct, delay or in any way interfere with the operation or safety of
the trains or traffic of the said railway.
4 Where, in effecting any such line or wire construction, it is necessary to erect
poles between the tracks of the railway, the applicant, before any work is begun, shall
APPENDIX D— CROSSING REGULATIONS 205
give the railway company owning, operating, or using the said railway at least seventy-
two hours' prior notice thereof in writing, and the said railway company shall be
entitled to appoint an inspector, under whose supervision such work shall be done, and
whose wages, at a rate not to exceed three dollars per day, shall be paid by the appli-
cant. When the applicant is a municipality and the work is on a highway under its
jurisdiction, the wages of the inspector shall be paid by the railway company.
4^ (a) It shall not, however, be necessary for the applicant to give prior notice
in writing to the railway company as above provided1 in regard to necessary work to
be done in connection with the repair or maintenance of the lines or wires when such
work becomes necessary through an unforeseen emergency.
5 Where the wires or cables are to be erected at the railway and carried above,
below, or parallel with existing wires, either within the span or spans to be constructed
at the railway or within the spans next thereto on either side, such additional pre-
cautions shall be taken by the applicant as the Engineer of the Board shall consider
necessary.
6 Nothing in these conditions shall prejudice or detract from the right of the
company owning, operating, or using the railway to adopt at any time the use of
electric or other motive power, and to place and' maintain along, over, upon, or under
its right of way, such poles, lines, wires, cables, pipes, conduits, and other fixtures and
appliances as may be necessary or proper for such purposes. Liability for the cost of
any removal, change in location or construction of the poles, lines, wires, ca'bles or
other fixtures or appliances erected by the applicant along, ovsr or under the tracks
of the said railway company, rendered necessary by any of the matters referred to in
this paragraph, shall be fixed by the Board on the application of any party interested.
7 Any disputes, arising between the applicant and the said railway company as
to the manner in which the said1 wires or cables are to be erected, placed or main-
tained, used or repaired, shall be referred to the Engineer of the Board, whose decision
shall be final.
8 The wires or cables of the applicant shall be erected, placed and maintained
in accordance with the drawings approved by the Board and the specifications following.
If the drawing and1 specifications differ the latter shall govern unless a specific state-
ment to the contrary appears in the Order of the Board.
9 In every case in which the line of a railway -company is to be constructed
along or under the wires or cables of a telegraph or telephone company, the construc-
tion of the telegraph or telephone line or lines of the company shall be made to con-
form to the foregoing specifications, and any changes necessary to make it so conform
shall be made by the telegraph or telephone company at the cost and expense of the
railway corrpany.
OVERHEAD LINES
Specifications
A Labelling of poles. — Poles, towers, or other wire-supporting structures on each
side of and adjacent to railway crossings, to be equipped with durable labels showing
(a) the name of the company or individual owning or maintaining them, and (ft)
the maximum voltage between conductors; the characters upon the labels to be easily
distinguished from the ground.
B Separate lines. — Two or more separate lines for the transmission of electrical
energy shall not be erected or maintained in the same vertical plane. The word
" lines," as here used, to mean the combination of conductors and! the latter's support-
ing poles, or towers and fittings.
0 Location of poles, etc. — Pole% towers, or other wire-sup'wrting structures to
be located generally a distance from the rail not less than equal to the length of the
poles or structures used. Poles, towers, or other wire-supportin? structures must
206 METHODS OF COMMUNICATION FOR FOREST PROTECTION
und'er no consideration be placed less 'than 12 ft. from the rail of a main line, or less
than 6 ft. from the rail of a siding. At loading sidings sufficient space to te left
for driveway.
D Setting and strength of poles. — Poles less than 50 ft. in length to be set not
less than 6 ft. and poles over 50 ft. not less than 7 ft. i-n solid ground. Poles with
side strains to be reinforced with braces and guy wires. Poles to be at least 7 in.
in diameter at the top — mountain cedar poles to be at least 8 in. at the top. In
soft ground poles must be set so ,as to obtain the same amount of rigidity as would
be obtained by the above specifications for setting poles iii solid ground. When the
line is located in a section of the country where grass or other fires might burn them,
wooden poles to be covered with a layer of some satisfactory fire-resisting material,
such as concrete at least two in. thick, extending from the butt of the pole for a
distance of at least 5 ft. above the level of the ground. Wooden structures to have
a safety factor of 5.
E Setting and strength of other structures. — Towers or other structures to be
firmly set upon stone, metal, concrete or pile footings or foundations. Metal and
concrete structures to have a safety factor of 4.
E Length of Span. — Span must be as short as possible consistent with the rules
of setting and locating of poles and towers.
G Fittings of wooden poles for telegraph, telephone, or similar low-tension lines.
— The poles at each side of a railway must be fitted with double cross-arms', dimensions
not less than 3 in. by 4 in., each equipped with 1^-in. hardwood pins, nailed in arms,
or some stronger support and with suitable insulators; cross-arms to be securely
fastened to the pole in a gain by not less than a f-in. bolt through the pole; arms
carryiiig more than two wires or carrying cable must be braced by two stiff iron or
substantial wood braces fastened to the arms by -§-in. or larger bolts, and to the pole
by a f-in or. larger bolt.
H Fittings of all poles, towers, or other structures.— All wire-supporting structures
to be equipped with fittings satisfactory to the Engineer of the Board.
I Guards. — Where cross-arms are used, an iron hook guard to be placed on the
ends of and securely bolted to each. The hooks shall be so placed as to engage the
wire in the event of the latter's detachment from the insulators.
J Insulators. — All wires or conductors for the transmission of electrical energy
along or across a railway to be supported by and securely attached to suitable insula-
tors.
Wires or conductors in 10,000-volt (or higher) circuits, to be supported by insula-
tors capable of withstanding tests of two and one-half times the maximum voltage to
be employed under operating conditions. An affidavit describing the tests to which
the insulators have been subjected and the apparatus employed in the tests shall be
supplied by the applicant. The tests upon which reports are required are as follows: —
Ja Puncture or rupture test. — The insulators having been immersed in water for
a period of seven days, immediately preceding and ending at the time of the test, to
be subject for a period of five minutes to a potential of two aiid one-half (2-5) times
the maximum potential of the line upon which they are to.be installed.
Jb Flash-over test. — State the potentials that were employed to cause arcing or
flashing across the surface of the insulator between the conductor and the insulator's
point of support when the surface was (1) dry, and (2) wet.
K Height of wires (a) Low-tension conductors. — The lowest conductor must not
be less than 25 ft. from top of rail for spans up to 145 ft.; 2£ ft. additional clearance
APPENDIX D— CROSSING REGULATIONS 207
of rails or other wires must be given for every 20 ft. or fraction thereof additional
length of span. The words " low-tension," as here used, to mean conductors for
telegraph, telephone, and kindred signal work, as well as conductors connected with
grounded secondary circuits of transformers below 350 volts.
Kb All primary conductors, ungrounded secondaries, and railway feeders to be
maintained at least 30 ft. above the top of rail — except where special provisions are
made for trolley wires.
Kc High-tension conductors, those between which a potential of 10,000 volts or
over is employed, to be maintained at least 35 ft. above the top of rail.
L Clearances. — 'Safe clearances between all conductors to be maintained at all
times. The following distances to be provided wherever possible; at least 3 ft. clear-
ance from low-tension wires; at least 5 ft. between low-tension wires, primaries,
ungrounded secondaries, and railway feeders employing less than 10,000 volts; at
least 10 ft. between high-tension wires and all other lines.
M Guy wires. — 'Guy wires at railway crossings to be at least as strong as 7-strand
No. 1'6 'Stub's or New British 'Standard gauge galvanized steel wire, and to be clearly
indicated as guy wire on the drawing accompanying the application. One or more
strain insulators to be placed in all guy wires; the lowest strain insulator to be not
less than 8 ft. above the ground.
Na Wires and other conductors. — Where open telephone, telegraph, signal or
kindred low-tension wires are strung across a railway this stretch to consist of
copper wire, or copper-clad steel wire, not less than No. 13 New British Standard
.gauge, -09'2 in. in diameter. Wire is to be securely tied to insulators by a tie wire not
less than 20 in. in length and of the same diameter as the line wire,
Nb Where No. 9 iB.W.G., or larger, galvanized iron or steel wire is employed in
a circuit, and where there is no danger of deterioration from smoke or other gases,
the use of this wire may be continued at the crossing.
Nc Where a number of ru'bber-covered wires are strung across a railway they
may be made up into a cable by being twisted on each other or otherwise held together
and the whole securely fastened to the poles.
Nd Wires or other conductors for the transmission of electrical energy for pur-
poses other than telegraph^ telephone, or kindred low-tension signal work, to be com-
posed of at least seven strands of material having a combined tensile strength equiva-
lent to or greater than iNo. 4 B. & S. gauge hard-drawn copper wire. These con-
ductors to be maintained above low-tension wires at the crossing, to be free from
joints or splices, and to extend at least one full span of line beyond the poles or
towers at each side of the railway.
Ne Wires or other -conductors subject to potentials of 10,000 volts or over, to be
reinforced by clamps, servings, wrappings, or other protection at the insulators to
the satisfaction of the Engineer of the Board.
Nf Conductors for other than low-tension work to have a factor of safety of 2
when covered with ice or sleet to a depth of 1 in. and subjected to a wind pressure
of 8 pounds per square ft. on the ice-covered diameter.
Ng All conductors to be dead-ended or so fastened to their supporting insulators
at each side of the crossing that they cannot slip through their fastenings.
0 Positions of wires. — Wires or conductors of low potential to 'be erected and
maintained below those of higher potential which may be attached to the same poles
or towers.
P Trolley wires. — Trolley wires at railway crossings to be provided with a trolley
guard so arranged as to keep the trolley wheel or other rolling, sliding or scraping
device in electrical contact. The trolley wire, trolley guard, and their supports to be
maintained at least 22 ft. 6 in. above the top of the rails.
208 METHODS OF COMMUNICATION FOR FOREST PROTECTION
Q Cable. — Cable to be carried on a suspension wire at least equivalent to seven
strands of No. 13 Stub's or New British Standard gauge galvanized steel wire. When
cross-arms are used, suspension wires to be attached to a |-in. iron or stronger hook,
or when fastened to poles to a malleable iron or stronger messenger hanger bolted
through the poles, the cable to be attached to the suspension wire by cable clips not
more than 20 in. apart. Rubber insulated cables of less than f in. in diameter may
be carried on a suspension wire of not less than seven strands of No. 16 Stub's or
New British Standard gauge galvanized steel wire. The word " cable " as here used,
to mean a number of insulated conductors bound together.
PART II — UNDERGROUND LINES
Conditions
1 The line or lines, wire or wires, shall be carried along or across the railway
in accordance with the approved drawing, and a pipe or pipes, conduit or conduits,
cable or cables shall, for the whole width of the right of way adjoining the highway,
be laid at the depth called for by, and shall be constructed and maintained in accord-
ance with the specifications hereinafter set forth.
2 All work in connection with the laying and maintaining of each pipe, conduit
or cable and the continued supervision of the same shall be performed by, and all
costs and expenses thereby incurred be borne and paid by the applicant; but no work
shall at any time be done in such a manner as to obstruct, delay or in any way inter-
fere with the operation or safety of the trains, traffic or other work on the said rail-
way. f
3 The applicant shall at all times maintain each pipe, conduit or cable in good
order and condition, so that at no time shall any damage be caused to the property
of the railway company or any of its tracks be obstructed, or the usefulness or safety
of the siame for railway purposes be impaired, or the full use and enjoyment thereof
by the said railway company be in any way interfered with.
4 Before any work of laying, removing, or repairing any pipe, conduit or cable
is begun, the applicant shall give to the railway company at least seventy-two hours
prior notice thereof, in writing, accompanied by a plan and profile of the part of
the railway to be affected, showing the proposed location of such pipe or conduit and
works contemplated in connection therewith, and the said railway company shall be
entitled to appoint an inspector to see that the applicant, in performing said work,
complies, in all respects, with the terms and conditions of this order, and whose
wages, at a rate not exceeding $3 per day, shall be paid by the applicant. When the
applicant is a municipality and the crossing is on a highway under its jurisdiction
the wages of the inspector shall be paid by the railway company.
4a It shall not, however, be necessary for the applicant to give prior notice in
writing to the railway company, as above provided, in regard to necessary work to be
done in connection with the repair or maintenance of the line when such work becomes
necessary through an unforeseen 'emergency.
5 The applicant shall, at all times, wholly indemnify the company owning, operat-
ing, or using the said railway of, from, and against all loss, costs, damage, and
expense to which the said railway company may be put by reason of any damage or
injury to person or property caused by any pipe, conduit, or cable, any works or appli-
ances herein, or in the order authorizing the work provided for, not being laid and
constructed in all respects in compliance with the terms and provisions of these con-
ditions, or if, when so constructed and laid, not being at all times maintained and
kept in good order and condition and in accordance with the terms and provisions of
said order, or any order or orders of the Board in relation thereto, as well as any
damage or injury resulting from the imprudence, neglect, or want of skill of any of
the employees or agents of the applicant.
APPENDIX E— STANDARD SPECIFICATIONS 209
6 Nothing in these conditions shall prejudice or detract from the right of any
company owning or operating or using the said railway to adopt, at any time, the use
of electric or other motive power, and to place and maintain upon, over, and under
the said1 right of way such poles, wires, pipes, and other fixtures and appliances as may
be necessary or proper for such purposes. Liability of the cost of any removal, change
in location or construction of the pipes, conduits, wires, or cables constructed or laid
by the applicant rendered necessary by any of the matters referred to in this para-
graph, shall be fixed by the Board on the application of the party interested.
7 Any dispute arising between the applicant and the company owning, using or
operating said railway as to the manner in which any pipe or conduit, or any works
or appliances herein provided for, are being laid, maintained, renewed, or repaired,
shall be referred to the Engineer of the Board, whose decision shall be final and
binding on all parties.
UNDERGROUND LINES
Specifications
AA Conduit. — Vitrified clay, creosotei wood, metal pipe, armoured cable or fibre
conduit may be used.
BB Depth. — The excavation to be of sufficient depth to .allow the top of the d*uct
to be at least three ft. below the bottom of the ties of the railway track.
CO Laying. — The conduit or duct to 'be laid on a base of 3 in. of concrete, mixed
in proportion, 1 of cement, 3 of sand, and 5 of broken stone or gravel. Where stone
is used, such stone is to be of a size that will permit of its passing through a 1-in.
ring. After dlucts are laid, the whole to be encased to a thickness of 3 in. on top
and sides in concrete mixed in the same proportions as above.
Where the track is on ,an embankment a pipe may be driven through the latter.
DD Filling in. — The excavation must be filled' in slowly and well tamped on top
and side.
EE Guard. — The excavation must at all times be safely protected by the appli-
cant.
APPENDIX E
FORESTRY BRANCH STANDARD SPECIFICATIONS
1— Specifications for Galvanizing
(a) General. — All iron and steel materials requiring galvanizing shall be pre-
pared according to the following requirements : —
The galvanizing shall consist of a deposition of zinc laid on by either the hot
or electric process ; this coating shall be evenly and uniformly applied over the entire
surface; all holes, grooves, threads, or other irregularities of surface shall be thor-
oughly coated, and there shall be no excess deposit, rough places, or other imperfec-
tions. All galvanizing of parts intended to fit together shall be so performed that
such parts can be readily and properly assembled.
(b) Test.— All galvanized equipment shall be required to pass the following test,
a reasonable quantity of each shipment not to exceed 10 per cent being selected for
test and the shipment passed or rejected on the basis of test: —
The sample snail be immersed in the standard solution of copper sulphate for
one minute, removed, wiped dry, and! cleaned. This process shall be repeated until
79211—14
210
METHODS OF COMMUNICATION FOR FOREST PROTECTION
four (4) immersions in all have been made, and thereafter if any deposits of copper
or any red spots appear on the sample, or if the galvanizing appears corroded or
removed, the sample shall be considered defective and the shipment represented by
the sample rejected.
/
(c) Standard Solution. — The standard solution of copper sulphate shall consist
of a solution of commercial copper sulphate crystals in water having a specific
gravity of 1-185 at 70° F. The" temperature of the solution shall not exceed 70° F.
nor fall below 60° F. while the sample is beinig tested.
2 — Specifications for Galvanized-iron Telephone Wire
General description. — The finished product desired under these specifications
consists of galvanized B.B. wire as hereinafter specified.
Finish. — The wire shall be cylindrical in form and free from scales, inequali-
ties, flaws, splints, and other imperfections. The finish of the wire shall be in
accordance with the best commercial practice. Each coil shall be warranted not to
contain any weld, joint, or splice in the rod before drawn.
Galvanizing. — The wire shall be well galvanized in accordance with the speci-
fications for the galvanizing of iron and steel given in Specifications No. 1.
ELECTRICAL REQUIREMENTS
Electrical resistance. — The resistance of the wire in ohms per mile at a tempera-
ture of 68° F. shall not exceed the quotient arising from dividing the constant
number, fifty-six hundred (5,600), by the weight of ihe wire in pounds per mile.
MECHANICAL REQUIREMENTS
Dimensions. — The diameter of the galvanized wire shaH be within the limits
given in the following table: —
Gauge No.,
B.W.G.
Diameter of galvanized wire, in
inches
Gauge No.,
B.W.G.
Diameter of galvanized wire, in
inches
Maximum
Gauge
Minimum
Maximum
Gauge
Minimum
6
8
0-207
0-169
0-152
0-203
0-165
0-148
0-198
0-161
0-144
10...
12
14
0-138
0-112
0-086
0-134
0-109
0-083
0-130
0-105
0-080
9 . ..
Breaking weight. — The breaking weight of the wire shall not be less than two
and eight-tenths (2-8) times the weight of the wire in pounds per mile.
Torsion. — The wire shall be capable of withstanding at least fifteen twists in a
length of 6 in.
Coils. — The length of the wire in each coil shall be as follows: No. 6 B.W.G.,
approximately J mile; Nos. 8, 9, 10, 12 and 14 B.W.G., approximately i mile.
In the case of wire less than 0-134 in. in diameter, one-third of the coils may have
two pieces to a coil, joined by the ordinary twist joint carefully soldered and galvanized.
In the case of wire 0-134 in. in diameter, and larger, each coil may consist of two
pieces only, joined by the ordinary twist joint carefully soldered and galvanized.
Binding. — Each coil of wire shall be securely bound in at least four places with
galvanized iron wire. A tag shall be attached to each coil giving the size and grade
of wire in the coil.
APPENDIX E— STANDARD SPECIFICATIONS
211
3— Specifications for Hard-drawn Copper Telephone Wire
General. — The material shall be copper of such quality and purity that when
drawn hard it shall have the properties and characteristics herein required. The
manufacture, workmanship, and finish must be in accordance with the best commercial
practice.
Manufacture. — Each coil shall be drawn in one length and be exempt from joints
or splices. All wire shall be truly cylindrical and shall conform to gauge within the
limits of variation permitted by these specifications. It must not contain any scale,
inequalities, flaws, cold shuts, seams, or other imperfections.
MECHANICAL AND ELECTRICAL REQUIREMENTS
Diameter in mils
Weights per mile
in pounds
Breaking wts.
in pounds
Wts. of
coils, pounds
Conduc-
tivity
ll
o
-o
1
3
imum
imum
1
"3
|
imum
•|'3
ctual
imum
s
g-g
CO a
imum
imum
1
!mum
.58
ll
'£""
if
0
&
1
.a
1
1
S
^g
's
I
e
S
e
S
Q) O
fV*3
B.W.G.
%
%
8
128
130
127
260
264
258
818
800
63,100
219
151
97
96
40
1-05
B. & S.G.
10
101-9
102-8
101-0
165-0
168-0
162-0
540
519
64,800
218
152
97
96
40
0-99
12
80-0
81-2
79-3
102-6
105-7
100-8
334
327
66,500
72
52
97
96
44
0-94
14
64-0
65-0
63-0
65-0
67-5
63-0
220
212
68,200
97
96
47
0-91
Shipping. — The wire shall be made up into coils the eye of which shall have a
maximum diameter of 22 in. and a minimum diameter of 18 in., and shall be securely
tied by not less than four separate pieces of strong twine, and shall be protected by a
sufficient wrapping of burlap so that the wire may not be injured during transporta-
tion. The wrappings shall be placed upon the wire bundles, after they have been coiled
and secured by the twine. Each coil shall have its gauge, length, and weight plainly
and indelibly marked upon two brass tags which shall be secured to the coil, one inside
the wrapping and the other outside.
4 — Specifications for Emergency Wire
General. — This wire will be used under all climatic and weather conditions and
will be laid out on the ground, or on trees, in continuous lengths not exceeding 30
miles, and without the use of insulators. The quality of the material used and the
method of manufacture shall be such as to ensure for the wire the properties herein
specified.
Conductor. — This wire shall have a conductor consisting of ten strands of No. 30
B. & S. gauge hard-drawn copper wire twisted together, the twists per foot not to be
less than eight and not more than ten.
Hard-drawn Copper Wire. — The hard-drawn copper wire shall be free from bends,
cuts of any dimensions, nicks, splits or splinters, spills, grooves, scraped, surface, wavy
surface, flat-sided or oval wire, corrosion, or any irregularities. The diameter of No.
'60 hard-drawn copper wire shall not be greater than -01013 in. nor less than -00993 in.
Covering.— A double reverse serving of cotton shall be applied to the twisted
conductor so as to form a close, smooth covering.
Weather-proofing.— The cotton covering shall be thoroughly saturated with a per-
manent weather-proof compound of such a nature as to preserve the strength of the
79211— 14i
212 METHODS OF COMMUNICATION FOR FOREST PROTECTION
cotton wrapping, shall not act injuriously thereupon, and shall be insoluble in water.
The compound shall adhere firmly to the cotton covering and shall not drop or run
when the finished wire is subjected to a temperature of 150° F. for thirty minutes,
and shall not crack when the wire is subjected to a temperature of 10° F. for thirty
minutes.
The diameter of the completed wire shall not be more than -048 in. and not less
than -043 in.
Spooling, — The wire shall be evenly wound on wooden spools weighing approxi-
mately three-quarters of a pound.
The inner end of the wire shall be brought out through the spool head.
The length of the wire shall be 2,640 ft. plus 100 ft.
The exact length of the wire shall be marked on the spool.
The wire on each spool shall be one continuous length.
•Splices. — Spliced joints shall be equal to or stronger than the wire itself and
shall be so made as not to materially increase the diameter of the conductor at the
point where the splice occurs.
Weight per mile. — The weight per mile of the finished wire shall not exceed
nineteen and a half (19-5) pounds and shall not be less than seventeen and a half
(17-5) pounds. This does not include the weight of the wooden spool.
Tensile Strength. — Tests shall be made on wire from the ends of which the insula-
tion has been removed. The finished wire shall have a minimum breaking weight of
forty-five (45) pounds and a minimum elongation of one-half of 1 per cent in a length
of 2 feet.
Resistance. — The resistance of this wire shall not be more than 60 ohms per mile
at a temperature of 68° F.
5 — Specifications for Rubber-covered Copper Wire
General. — The quality of the material used must be of the best, and the manu-
facture, workmanship, and finish must be in accordance with the best commercial
practice.
Manufacture. — The conductor shall be in one continuous length, cylindrical in
section, and uniformly drawn, so that the variation over or under the specified
diameter shall not exceed one (1) mil (one one-thousandth of an^ inch). It shall
be uniform in quality, free from factory joints, scales, splints, flaws, and other
imperfections. To ensure the removal of defects from the conductor the manufac-
turer shall cut off 2'5 ft., or ,as much more as may be necessary, from each end of
every coil.
Each conductor before being insulated shall be thoroughly and uniformly linned.
The tin coating nost conform to the following requirements: The tinned conductor
shall be immersed in a current of pure hydrogen sulphide gas, saturated with water
vapour at a temperature of not less than 75°F. and not more than 79°F. for four
hours. At the end of this time the conductor must exhibit no signs of blackening.
Insulation. — The tinned conductor shall be evenly and smoothly covered with
vulcanized rubber of the best quality, which is impervious to moisture, or some other
approved weather-proof, insulating compound to such a thickness as hereinafter
specified.
The dielectric shall adhere firmly to the conductor and shall not act injuriously
upon it. The wire shall be well centred in the dielectric. The dielectric shall not
soften sufficiently to allow decentralization at a lower temperature than 130° F.
APPENDIX E— STANDARD SPECIFICATIONS 213
The insulated' conductor shall 'be sufficiently flexible to stand being twistel three
times about itself, left for at least sixteen hours, and untwisted without the dielec-
tric showing any signs of rupture.
Electrical Requirements. — The insulation test shall be made on the outside dis-
tributing conductor whilst in water, the conductor having been previously submerged
in water for at least twelve hours prior ,to the test. All conductors, No. 16 B & S.
gauge and over, shall show an insulation resistance of not less than 500 megohms
per mile; and conductors under No. 16 B. & S. gauge shall have an insulation
resistance of not less than 250 megohms per mile. The temperature at which test
is to be made shall not be less than 60°F. nor more than 70°F.
The test for insulation resistance shall be made with an electro-motive force of
not more than 550 volts, the insulation resistance to be figured from the deflection
obtained with the negative pole of the source of potential connection to the conductor
and after an electrification of one minute. If unequal deflections are obtained with
the positive and negative poles connected to the wire, the insulation shall be considered
defective.
Mechanical Requirements. — These include breaking weight, elongation, and braid-
ing.
The breaking weight for No. 14 B. & S. gauge wire shall not be less than one
hundred and ninety (190) pounds; for No. 16 B. & S. gauge wire, not less than one
hundred and twenty-five (125) pounds; and for No. 19 B. & S. gauge wire not less than
seventy (70) pounds.
The elongation in two feet 'shall not be less than 1 per cent for No. 14, No. 16,
and No. 19 B. & S. gauge wires.
As to braiding, each insulated conductor shall be covered writh a close, smooth
braid, which shall be thoroughly impregnated with a permanent weather-proof com-
pound. The impregnated braid shall then be uniformly covered with a continuous
layer of the compound which shall adhere firmly to the braid.
The compound shall not act injuriously on the dielectric or the braid, and shall
not melt when subjected to a temperature of 125° F., nor crack at a temperature of
30° F., and shall be insoluble in water.
Packing for Shipment. — The finished conductor shall be delivered in coils of one
continuous piece, the eye of the coil to be about nine inches. Both ends of the coil shall
be accessible.
Each coil shall be securely bound with strong tape or twine in at least four
separate places, and shall then be wrapped with burlap or strong paper to prevent
mechanical injury during transportation.
Each coil shall have its gauge and length plainly marked on two strong tags, one
tag to be attached to the coil and the other to the outside of the wrapping.
6— Specifications for Glass Insulators
The material desired under these specifications consists of glass insulators of
the style and dimensions hereinafter described.
General — 'The specifications and drawings are intended to include all instruc-
tions necessary to guide the manufacturer in his work. They are intended to co-
operate with and supplement each other so that any details indicated in one and not
in the other shall be executed as if indicated in both.
Workmanship.— All workmanship shall be of the best commercial grade.
'Material. — The insulators shall be made of transparent colourless or green glass.
Dimensions. — The insulators shall be of the style and dimensions shown in the
drawing attached hereto and: made part of these specifications.
214
METHODS OF COMMUNICATION FOR FOREST PROTECTION
Where maximum and minimum dimensions are shown the dimensions shall be
within the limts specified. Where limits are not shown the dimensions shall be
approximate.
The diameter of the thread shall be such that at least two revolutions of the
insulator will be required to tighten it on the standard insulator gauge, and when in
this position the end of the insulator gau^e shall not be more than one-eighth of an
inch from the crown of the insulator.
4 threads to the inch
A I Iowa ble Variations
over
under
0
w.
0
X
»%aH
o
y
o
ld/3a"
d
V&"
/8*
Specifications 6 Design of Forestry Branch standard pony glass insulator
The thread of all insulators shall be smooth and of uniform pitch. The thread,
shall be well centred in the insulator so that, when in place on the standard insulator
gauge, the gauge will not touch the inner surface of the petticoat.
Insulators conforming in all other respects to the requirements of these specifi-
cations, but having on the lower edge of ,their petticoats a series of projecting points,
may be accepted under these specifications.
Finish. — The insulators shall have a finish ensuring, so far as is consistent with
the best commercial practice, smooth even surfaces and freedom from flaws, cracks,
blow-holes, sharp edges, and other defects.
7 — Specifications for Split Tree Insulators
Material. — Split tree insulators .shall be made of the best grade of insulator
porcelain.
Finish. — The surface shall be prown-glazed except the faces which are to be
placed in contact in .attaching the insulator around the line wire. These may be left
white and unglazed. The glazed finish shall be smooth, without rough spots, cracks,
sharp edges, or other defects.
APPENDIX E— STANDARD SPECIFICATIONS
Workmanship. — All workmanship shall be of the best commercial grade.
215
Dimensions. — The insulators shall be of the type and dimensions shown in the
drawing attached hereto, and made a part of these specifications.
INSULATOR,
Specifications 7 Design of Forestry Branch' standard split tree insulator
8 — Specifications for Cedar Poles
Purchased poles not cut under the supervision of the Dominion Forestry Branch
shall be required to conform to the specifications of the Northern White Cedar Asso-
ciation if secured east of the Rocky mountains, or to those of the Western Red Cedar
Association if secured west of the Rocky mountains. For convenience and reference
extracts from these specifications are reprinted below: —
Northern White Cedar Association Specifications
" Sizes, 4 in., 25 ft. and upwards. Above poles must be cut from live, growing
cedar timber, peeled, and reasonably well proportioned for their length. Tops must
he reasonably sound, must measure in circumference as follows: seasoned1 4-in. poles,
12 in.; 5-in. poles, 15 in.; 6-in. poles, 1&J in,; 7-in. poles, 2® in. If poles are green,
fresh cut, or water-soaked, then 4-in. poles must measure 12£ in.; 5-in. poles, 16 in.;
6-in. poles, 19i in. ; 7-in. poles, 22>f in. in circumference -at top end. Lengths may be
one-half inch, scant for each j5 ft. in length, and six inches long for any length from
20 ft, up.
"One way sweep allowable not exceeding 1 in. for every 5 ft.; for example, in
a 25-ft. pole, sweep not to exceed 5 in., and in a 40-ft. pole, 8 in. Measurement for
sweep shall be taken as follows: That part of the pole when in the ground (6 ft.) not
being taken into account in arriving at sweep, tightly stretch a tape-line on the side
of the pole where the sweep is greatest from a point 6 ft., from the butt to the upper
216 METHODS OF COMMUNICATION FOR FOREST PROTECTION
surface at top, and having so done measure widest point from tape to surface of pole
and if, for illustration, upon a 25-ft. pole said widest point does not exceed 5 in.,
said pole comes within the meaning of these specifications. Butt-rot in the centre
including small ring-rot outside of the centre; total rot must not exceed 10 per cent
of the area of the butt. Butt-rot of a character which plainly seriously impairs the
strength of the pole above ground is a defect. Wind-twist is not a defect unless very
unsightly and exaggerated. Kough, large knots, if sound and trimmed smooth, are
not a defect."
Western Red Cedar Association Specifications
"All poles must be cut from live, growing cedar timber, peeled, knots trimmed
close, butts and tops sawed square, tops must be sound and must measure as follows
in circumference: —
4-in. top, 12-in. circ. 7-in. top, 22-in. circ. 9-in. top, 28-in. circ.
5-in. top, 15-in. circ. 8-in. top, 25-in. circ. 10-in. top, 31-in. circ.
6-in. top, 18-J-in. circ.
" No pole shall have more than one crook and this shall be one way only, the
sweep not to exceed 1 in. to every 6 ft. in length. Same to be determined in the fol-
lowing manner : — Measurement for sweep shall be taken as follows : [Phat part of
the pole when in the ground (6 feet) not being taken into account in arriving at
sweep, tightly stretch a tape-line on the sidle of the pole where sweep is greatest, from
a point 6 ft. from butt to the upper surface at top, and, having so done, measure
widest point from tape to surface of pole and if, for illustration, upon a 30-ft. pole
said widest point does not exceed 5 in., said pole comes within the meaning of these
specifications.
" Butt-rot in centre, including small ring-rot, shall not exceed 10 per cent of
the area of the butt. Butt-rot of a character which impairs the strength of the pole
above ground is a defect.
"Large knots, if sound and trimmed smooth, are not a defect.
"A perfectly sound, dead or dry streak shall not be considered a defect when it
•loos not materially impair the strength of the pole."
APPENDIX E— STANDARD SPECIFICATIONS
9 — Specifications for Wooden Spools for Emergency Wire
217
The spool on which the emergency wire is to be wound is to be made in accord-
ance with the drawing attached hereto and made a part of these specifications. The
material is to be clear, straight-grained, thoroughly seasoned pine; the manufacture
Sketch of Emergency Wire Spoof
Specifications 9 Design of Forestry Branch standard emergency wire spool
is to be of the best grade and the spools are to be finished with two coats of shellac
varnish. The weight of the finished spool should be approximately three-quarters of
a pound.
10 — Specifications for Creosote
The oil used shall be the best obtainable grade of coal-tar creosote, that is, it
shall be a pure product obtained from coal-gas tar or coke-oven tar and shall be free
from any tar, oil or residue obtained from petroleum or any other source, including
coal-gas tar or coke-oven tar; it shall be completely liquid at 98° C. and shall be free
from suspended matter; the specific gravity of the oil at 38°C. shall be at least 1-03.
When distilled by the .common method (that is, using an 8-ounce retort, asbestos-
Covered with standard thermometer, bulb 4 in. above the surface of the oil) the creo-
sote, calculated on the basis of the dry oil, shall give no distillate .below 200°€., not
more than 5 per cent below 210°C., not more than 25 per cent below 235°C., and the
residue above 355°C. if it exceeds 5 per cent in quantity, shall be soft. The oil shall
not contain more than 3 per cent water.
218
METHODS OF COMMUNICATION FOR FOREST PROTECTION
11 — Specifications for Wooden Brackets
The articles desired under these specifications consist of oak pole-brackets, fitted
to take the standard insulator.
.Workmanship. — All workmanship shall be of the best commercial grade.
Material. — All brackets shall be made of sound oak, free from knots, checks or
cracks, sapwood, worm-holes, and brash wood. The grain of wood on 'all brackets
shall be practically parallel to the axis of the threaded portion of the bracket. The
grain from the right-angled corner at the end of the bracket shall not run below the
bottom thread ,on the opposite face of the bracket.
Pole Line Bracket
ALLOWABLE VARIATIONS
over
under
dc
'/&"
Ve"
of
'/8"
'/&"
I
'/*''
'/4"
Specifications 11 Design of Forestry Branch standard wooden bracket
All brackets shall be thoroughly seasoned' before being offered for inspection.
Dimensions. — The seasoned brackets shall be of the style and dimensions shown
in the drawing attached hereto and made part of these specifications. Where maxi-
mum and minimum dimensions are shown, the dimensions shall be within the limits
specified. Where limits are not shown, the dimensions shall be approximate. Figures
upon the drawings shall be followed in preference to scale measurements. '
Thread. — The threaded portion of the bracket shall be as nearly .as possible of a
circular cro,ss-seetion. The thread! shall be smooth and of a uniform pitch, ,and such
that a standard insulator can be readily screwed on to the bracket until the end of the
bracket touches the top of the insulator. When in this position there should be no per-
ceptible rocking or play of the insulator on the bracket.
Nail holes. — Each bracket ishall h,ave two nail holes as shown,' in the drawing
attached hereto. The nail holes shall be well centred and shall be perpendicular to
that face of the (bracket which makes an angle with the axis of the (thread.
APPENDIX F— SOLDERING
12 — Specifications for Outdoor Protector Mounting-boxes
219
The box used for mounting protector and switch for installation outdoors with
the 133'6 — J telephone set shall be onad'e of clear, straight-grained, thoroughly
seasoned pine, spruce, or Douglas fir, according to the drawing attached hereto, and
made a part of these specifications. Hinges and hasp shall be of brass fastened by
brass screws.
t_ , Cj ' "
: "5 §"~ f
rf
0
CD U (D 1
• i
\\
j
f-
in
C
0 o (D
FEONT • ELEVATION
SIDE • ELECTION
BfcCK • ELEU&TION
Specifications 12 Design of outdoor protector mounting-box
Finish. — The box shall be planed smooth inside and' out and treated with a coat
American Telephone and Telegraph Co. specifications, as follows: No. 3438 for 40-60
inside and out with two coats of best paint either .grey, dark green, brown, or black.
APPENDIX F
SOLDERING— METHODS AND MATERIALS
Approved Solders. — Approved solders are those made in accordance with the
American Telephone and Telegraph Co. specifications, as follows: No. 3438 for 40-60
iolder; No. 3439 for 45-55 solder; No. 3440 for 50-50 solder; No. 3441 for resiii flux
wire solder.
Approved Fluxes. — Approved fluxes are: (1) plumbers' candles for plumbing and
cable work; (2) resin; (3) the stick forms of flux made by the Northern Electric Co.,
and (4) that known as "Allen's" stick. No other form of flux (such as paste or
liquid soldering salts) is to be used.
Process. — All parts to be soldered must first be thoroughly cleaned by scraping,
filing-, rubbing with emery paper, or some other method. In cleaning galvanized iron,
take care not to scrape off all the galvanizing.
Heat the joint with the soldering-iron. Do not attempt to apply the solder with
the iron. Heating should be just sufficient to melt the resin of resin-core solder or ,of
the soldering stick, and the parts should then be thoroughly coated with the flux.
220 METHODS OF COMMUNICATION FOR FOREST PROTECTION
Copper rapidly oxidizes when heated in contact with the air, and solder will not
adhere to oxidized copper. The purpose of the flux, therefore, is to cover the surface
to be soldered while the temperature is still low, and prevent oxidation. Continue
the application of the hot iron until the joint has become hot enough to melt the solder
which will then flow readily. Do not try to apply resin-core solder with a hot iron
and its own flux to a cold surface nor to an oxidized joint.
45-55 Solder. — This solder is to be used for joining split sleeves in cable work,
and for large surfaces of metal which are to be soldered. It is also to be used in making
joints in old galvanized-iron wire, and similar work. In joining old galvanized wire,
clean the ends which are to be soldered with emery cloth and make a Western Union
joint; then solder by means of a ladle, using as a flux one of the approved stick forms.
Do not use more than is necessary to cause the solder to flow, and apply by rubbing
before the first pouring of the solder over the joint. If necessary, apply again after the
joint has been heated. A large well-tinned soldering iron may be used, if preferred,
instead of pouring the solder over the joint. In such a case the iron must be pressed
against the joint so as to warm it just enough to melt the flux when it is held against
it. After a coating of this has adhered, apply the hot soldering-iron again and, at the
same time, apply the 45-55 wire solder to the joint (do not put the solder on the
soldering iron). Wheii the solder melts, having derived its heat from the joint and
not from the iron, it will flow readily. A slight tap on the wire will help it to run
into the joint well. This solder is furnished in the form of i-in. wire in 10-pound
coils, or in bars of 1£ pounds weight, and orders must state in which form it is
required.
Resin Flux Wire Smolder. — Resin flux wire solder is to be used in solderiiig all wire
connections other than galvanized-iron wire, but it may also be used for this purpose
in new work, when it is done with a soldering-iroTi. It is also to be used for all work
where copper and brass are to be soldered. To use this solder for small work, such
as wire joints and terminals, apply to the joint a well-tinned soldering-iron, of suffi-
cient size for the work. In soldering terminals, first clean off all old solder and bits
of wire by meaiis of a hot iron and then give only one turn of the wire which
is to be soldered around the terminals. In larger work, use any convenient means to
heat the joint, remembering to get a coat of resin on before enough heat has been
applied to the metal to oxidize it, and that the metal to be soldered must be hot enough
to melt the solder and burn off the superfluous resin. This solder is furnished i-n
5- and 10-pound coils, and orders must state which size is required.
To Solder to Black Iron
(1) First thoroughly clean a strip on the pipe about |-in. wide and 2^-in long;
('21) Heat the cleaned place, either with the flame of a gasolene torch or a heated
iron, until it is hot enough to melt the soldering-stick;
(3) Distribute a coat of flux over this point by rubbing it with a soldering-stick;
(4) With a well heated soldering-iron distribute 45-55 solid-wire solder over the
cleaned space;
(5) Tightly wrap the wire, well cleaned, around the pipe, leaving at least f in.
between each turn;
(6) Fasten the end of the wire at the end of the coil by twisting it around the
wire leading from the pipe;
(7) Apply an additional coat of flux;
(8) Apply the 45-55 solid-wire solder in the regular manner.
Tinning Soldering-iron. — File the iron to the required shape and brightness, and
heat until it is only just hot enough to melt the resin of resin-cored solder but not
hot enough to change the colour of the bright copper by oxidatioii. When in this
condition, coat the part to be tinned with resin and apply heat until the solder melts
readily, when it will be found to flow freely on the iron. Do not let the flame come in
contact with the tinned part of the iron.
APPENDIX G
USEFUL TABLES
TABLE 1— WEIGHTS OF CEDAR POLES OF VARIOUS LENGTHS AND TOP
DIAMETERS
Length
Top
diameter
Weight,
seasoned
Weight,
green
Length
Top
diameter
Weight,
seasoned
Weight,
green
ft.
in.
pounds
pounds
ft.
in.
pounds
pounds
20
4
100
130
45
6
900
1,000
20
5
130
170
45
7
1,100
, 250
20
6
190
250
45
8
1,350
,500
25
4
150
200
50
6
1,150
,250
25
5
200
260
50
7
1,350
,450
25
6
250
325
50
8
1,700
1,850
25
7
350
425
55
6
1,350
1.500
30
5
275
350
55
7
1,700
1,875
30
6
350
425
55
8
2,200
2,400
30
7
' 450
500
30
8
575
630
60
6
1,700
1,800
60
7
2,200
2,350
35
5
375
500
60
8
2,500
2,700
35
6
450
600
35
7
600
750
65
6
2,200
2,450
35
8
850
990
65
7
2,500
2,800
65
8
3,000
3,400
40
6
625
840
40
7
850
1,075
70
6
2,500
2,900
40
8
1,100
1,325
70
7
3,000
3,500
70
8
4,000
4,600
TABLE 2 — NUMBER OF POLES OF DIFFERENT SIZES REQUIRED TO MAKE
UP A CARLOAD LOT
NUMBER PER LOAD
Not less than 175 and up to 225
SINGLE CARS
Poles 4 in. in diameter 25 ft. long.
5
25
'
6
25
'
7
25
«
6
30
«
7
30
7
35
'
15-0
lO'O
75
75
60
55
2'00
125
100
100
8-0
75
DOUBLE CARS
Poles 7 in. in diameter 40 ft. long.
7 45
55
60
65
NUMBER PER LOAD
Not less than 6'0 and up to 75
50 " 65
40 " 55
35 '.' 45
25 " 35
20 " 30
25s and 30s should be loaded on cars taking a minimum of 24,000 pounds; 35s
on cars taking a minimum of 30,000 pounds; double loads (40s and longer), on long
cars 30,000 pounds each or 60,000 pounds minimum for the double load.
All poles up to and including 7 inches, 35 feet, are loaded on single cars. All
poles over 35 feet 'in length are loaded on double cars.
221
222
METHODS OF COMMUNICATION FOR FOREST PROTECTION
TABLE 3 — COMPARISON OF WIRE GAUGES'
The sizes of wires are ordinarily expressed by an arbitrary series of numbers.
Unfortunately there are several independent numbering methods, so that it is always
necessary to specify the method1 or wire gauge used. The following table gives the
numbers and diameters in decimal parts of an inch for the various wire gauges used
in this country, Great Britain and the United (States.
Number of wire
gauge
Roebling or Wash-
burn and Moens
Brown and
Sharpe
Birmingham
or Stubs
English legal
standard
Old English or
London
inch
inch
inch
inch
inch
6-0
0-460
0-464
5-0
0-430
0-432
4-0
0-393
'"6-4600"'
0-454
0-400
0-4540"'
3-0
0-362
0-4096
0-425
0-372
0-4250
2-0
0-331
0-3648
0-380
0-348
0-3800
0
0-307
0-3249
0-340
0-324
0-3400
1
0-283
0-2893
0-300
0-300
0-3000
2
0-263
0-2576
0-284
0-276
0-2840
3
0-244
0-2294
0-259
0-252
0-2590
4
0-225
0-2043
0-238
0-232
0-2380
5
0-207
0-1819
0-220
0-212
0-2200
6
0-192
0-1620
0-203
0-192
0-2030
7
0-177
0-1443
0-180
0-176
0-1800
8
0-162
0-1285
0-165
0-160
0-1650
9
0-148
0-1144
0-148
0-144
0-1480
10
0-135
0-1019
0-134
0-128
0-1340
11
0-120
0-09074
0-120
0-116
0-1200
12
0-105
0-08081
0-109
0-104
0-1090
13
0-092
0-07196
0-095
0-092
0-0950
14
0-080
0-06408
0-083
0-080
0-0830
15
0-072
0-05706
0-072
0-072
0-0720
16
0-063
0-05082
0-065
0-064
0-0650
17
0-054
0-04525
0-058
0-056
0-0580
18
0-047
0-04030
0-049
0-048
0-0490
19
0-041
0-03589
0-042
0-040
0-0400
20
0-035
0-03196
0-035
0-036
0-0350
21
0-032
0-02846
0-032
0-032
0-0315
22
0-028
0-02534
0-028
0-028
0-0295
23
0-025
0-02257
0-025
0-024
0-0270
24
0-023
0-02010
0-022
0-022
0-0250
25
0-020
0-01790
0-020
0-020
0-0230
26
0-018
0-01594
0-018
0-018
0-0205
27
0-017
0-01419
0-016
0-0164
0-01875
28
0-016
0-01264
0-014
0-0148
0-01650
29
0-015
0-01125
0-013
0-0136
0-01550
30
0-014
0-01002
0-012
0-0124
0-01375
31
0-0135
0-00893
0-010
0-0116
0-01225
32
0-0130
0-00795
0-009
0-0108
0-01125
33
0-0110
0-00708
0-008
0-0100
0-01025
34
0-0100
0-00630
0-007
0-0092
0-0095
35
0-0095
0-00561
0-005
0-0084
0-0090
36
0-0090
0-00500
0-004
0-0076
0-0075
37
0-0085
0-00445
0-0068
0-0065
38
0-0080
0-00397
0-0060
0-0057
39
0-0075
0-00353
0-0052
0-0050
40
0-0070
0-00314
0-0048
0-0045
English Legal Standard Gauge. — Also called New British Standard Gauge, or
British Imperial .Standard, and very commonly used, in Great Britain and this
country.
Birmingham Gauge. — Used largely in Great Britain and some of the British
Dominions for the measurement of wires of all kinds. In the United States it is
applied mostly to the measurement of iron wire.
APPENDIX G— USEFUL TABLES
223
Brown & Sharpe Gauge. — The United States standard for wires for electrical
purposes.
Law of the Brown & Sharpe Gauge. — The diameters of wires on the B. & S.
gauge are obtained from the geometric series in which No. 0000=0.4600 inch and
No. 36= -005 inch, the nearest fourth significant figure being retained in the
areas and diameters so deduced.
Let n == gauge number (0000 = - 3; 000 == — 2; 00 = - 1).
d == cKameter of wire in inches.
Then d = 0-3249
1-128*
Sheathing core. — The number (N) of sheathing wires having a diameter (d)
which will cover a core having a diameter (-D) is
N =
D+d
TABLE 4— TENSILE STRENGTH OF BARE COPPER WIRE
Numbers, B. & S.G.
Breaking weight
in pounds
Numbers, B. & S.G.
Breaking weight
in pounds
Hard-drawn
Annealed
Hard-drawn
Annealed
0000
8,310
6,580
5,226
4,558
3,746
3,127
2,480
1,967
1,559
1,237
980
778
5,650
4,480
3,553
2,818
2,234
1,772
1,405
1,114
883
700
555
440
9
617
489
388
307
244
193
153
133
97
77
61
48
349
277
219
174
138
109
87
69
55
43
34
27
000
00
0
10
11
12 -
13.
1
2 ,
3
4
14
15
16
17...
18
19
20
5
6
7
8
The strength of soft copper wire varies from 32,000 to 36,000 pounds per square
inch, and of hard copper wire from 45,000 to 68,000 pound's per square inch, accord-
ing to the degree of hardness.
The above table is calculated for 34,000 pounds for soft wire and 60,000 pounds
for hard wire, except for some of the larger sizes, where the breaking weight per
square inch is taken at 50,000 pounds for 0000, 000, and 00, 55,000 for 0, and
57,000 pounds for 1.
TABLE 5— PROPERTIES OF HARD-DRAWN COPPER TELEPHONE AND TELEGRAPH
WIRE
Furnished
Approximate size
Size B. & S.G.
Resistance
Breaking
Weight
in coils as
E.
B. B. iron wire
per mile
strength
per mile
follows
equal to copper
in conductivity.
Ohms
Pounds
Pounds
Miles
9...
4-30
625
209
1-0
2
10
5-40
525
166
1-2
3
11
6-90
420
131
0-52
4
12
8-70
330
104
0-65
6
Iron-wire gauge.
13
10-90
270
83
1-20
6*
14
13-70
213
66
1-50
8
(B.W.G.)
15
17-40
170
52
2-00
9
16
22-10
130
41
1-20
10
224
METHODS OF COMMUNICATION FOR FOREST PROTECTION
In handling- this wire the greatest care should be observed1 to avoid kinks, bends,
scratches, or cuts. Joints should be made only with copper splicing sleeves and
connectors.
On account of its conductivity being about five times that of E. B.B. iron wire,
and its breaking strength over three times its weight per mile, copper may be used
of which the section is smaller and the weight less than an equivalent iron wire,
allowing a greater number of ^ires to be strung on the poles.
Besides this advantage, the reduction of section materially decreases the elec-
tro-static capacity, while its non-magnetic character lessens the self-induction of the
line, both of which features tend to increase the possible speed of signalling in tele-
graphing, and to give greater clearness of enunciation over telephone lines, especially
those of great length.
TABLE 6— PROPERTIES OF BIMETALLIC WIRE 1
Numbers,
B. & S.G.
Diam-
eters
in mils
Weights
per mile
in pounds
Breaking
weight in
pounds
Numbers,
B. & S. G.
Diam-
eters
in mils
Weights
per mile
in pounds
Breaking
weight in
pounds
0000...
000
460
410
3,200
2 537
10,500
8 600
7...
8
144
128
314
246
1 210
1 020
00
365
2,022
7,000
9
114
203
850
0
325
1,620
5,700
10
102
157
660
1
2
289
258
1,264
1 003
4,600
3,800
11
12
91
81
127
100
520
410
3
229
797
3 200
14
64
63
260
4...
5
204
182
629
490
2,600
1,790
16
18
51
40
40
25
160
100
6
162
398
1,500
Adapted from " Wire in Electrical Construction " by John A. Roebling's Sons Co.
This wire consists of a steel centre with a cover of copper. Its conductivity is
about 65 per cent of that of pure copper. The percentage of copper and steel may
vary a trifle, hence the strength and weight must be approximate.
TABLE 7— PROPERTIES OF GALVANIZED TELEPHONE AND TELEGRAPH WIRE.1
Approximate
Approximate breaking
Resistance per mile (Interna-
Diameter
Area
weight in pounds
strain in pounds
tional ohms)at 68°F. or 20°
Size
in
in
C.
B\\T (~~*
*1 rl
• i
. W . U".
mils — d
circu.i<ii
mils = d2
per 1000
per
feet
mile
E.B.B.
B.B.
Steel
E.B.B.
B.B.
Steel
0
340
115,600
313
1,655
4,138
4,634
4,965
2-84
3-38
3-93
i
300
90,000
244
1,289
3,223
3,609
3,867
3-65
4-34
5-04
2
284
80,656
218
1,155
2,888
3,234
3,465
4-07
4-85
5-63
3
259
67,081
182
960
2,400
2,688
2,880
4-90
5-83
6-77
4
238
56,644
153
811
2,028
2,271
2,433
5-80
6-91
8-01
5
220
48,400
131
693
1,732
1,940
2,079
6"-78
8-08
9-38
6
203
41,209
112
590
1,475
1,652
1,770
7-97
9-49
11-02
7
180
32,400
87
463
1,158
1,296
1,389
10-15
12-10
14-04
8
165
27,225
74
390
975
1,092
1,170
12-05
14-36
16-71
9
148
21,904
60
314
785
879
942
14-97
17-84
20-70
10
134
, 17,956
49
258
645
722
774
18-22
21-71
25-29
11
120
14,400
39
206
515
577
618
22-82
27-19
31-55
12
109
11,881
32
170
425
476
510
27-65
32-94
38-23
13
95
9,025
25
129
310
347
372
37-90
45-16
52-41
14
83
6,889
19
99
247
277
297
47-48
56-56
65-66
15
72 .
5,184
14
74
185
207
222
63-52
75-68
87-84
16
65
4,225
11
61
152
171
183
77-05
91-80
106-55
3From American Steel and Wire Co.
APPENDIX G— USEFUL TABLES
TABLE 8— PROPERTIES OF GALVANIZED STEEL WIRE'
225
Approxi-
Approxi-
mate
mate
Approxi-
breaking
Approxi-
breaking
mate
strain in
Resist-
mate
strain in
Resist-
Size
Diam-
eter in
weight
in
pounds,
figured
ance
in
Size
Diam-
eter in
weight
in
pounds,
figured
ance
in
B.W.G.
mils
pounds
on the
ohms
B.W.G.
mils
pounds
on the
ohms
per
1,000
basis of
100,000
per
1,000
IPOOO
basis of
100,000
per
1,000
ft.
pounds
ft.
ft.
pounds
ft.
per sq. in.
per sq. in.
0
340
313
9,079
0-74
9
148
60
1,720
3-92
1
300
244
7,068
0-95
10
134
49
1,410
4-79
2
284
218
6,335
1-07
11
120
39
1,131
5-98
3
259
182
5,268
1-28
12
109
32
933
7-24
4
238
153
4,449
1-52
13
95
25
709
9-93
5
220
131
3,801
1-78
14
83
19
541
12-44
6
203
112
3,237
2-09
15
72
14
407
16-64
7
180
87
2,545
2-66
16
65
11
332
20-18
8
165
74
2,138
3-16
1From the Simplex Manual.
The strength of steel wire varies from 50,000 pounds per sq. in. to 300,000. pounds
and over, depending on the kind and treatment of material.
By using the values of breaking strain shown in the above column the breaking
strain figured on any other basis than 100,000 pounds per sq. in. may easily be
computed1. For example, with a wire with a breaking strain of 80,000 pounds per
sq. in., take eight-tenths of the tabulated breaking strain for whatever size of wire
the actual breaking strength is desired.
TABLE 9— PROPERTIES OF RUBBER-COVERED, LEAD-INCASED COPPER CABLES. »
Size B. & S.
Number
of wires in
conduct-
or
Thickness
of rubber
in frac-
tions of an
inch
Thickness
of lead
in frac-
tions of an
inch
List
number
Approx.
diameter
outside
of lead
in frac-
tions of an
inch
Approx.
weight
per
1000ft.,
pounds
4
1
4-64
3-64
774
29-64
477
6 .
1
4-64
3-64
776
26-64
391
8
1
3-64
3-64
778
22-64
298
10.
1
3-64
3-64
780
21-64
256
12 .
1
3-64
2-64
782
18-64
156
14
3-64
2-64
784
16-64
138
4.... . .
1
4-32
4-64
794
39-64
773
6 .
1
4-32
4-64
796
36-64
686
8
1
4-32
4-64
798
34-64
596
4...
4. .
1
1
7-32
7-32
5-64
3-32
743
744
53-64
55-64
1,232
1,485
6
1
5-32
4-64
745
40-64
764
6
1
6-32
5-64
746
46-64
1,061
6...
1
6^32
3-32
747
48-64
1,211
6 . .
1
7-32
5-64
748
50-64
1,186
6 .
1
7-32
3-32
749
52-64
1,357
8
1
5-32
4-64
750
38-64
722
8. .
1
6-32
5-64
751
44-64
993
8
1
6-32
3-32
752
46-64
1,171
8
1
7-32
5-64
753
48-64
1,114
8
1
7-32
3-32
754
50-64
1 , 306
JAdapted from America Steel and Wire Co.
79211—15
226
METHODS OF COMMUNICATION FOR FOREST PROTECTION
PQ
C<) O
S 8
<N •*
T^l »0
8
PQ w-
f
ec §
25
CO OO
lO OO
CC OO
0 M
OS i— i
PQ
PQ
*r *?
O5 O CO
t— I IO ^
CO
o
§
%
O
N
PQ
s
t^ CO CO
CO CO t>» CO
^ CO
CO OO
2 ^ ^
(M
pq
.2
a *s-s ^ . .: § •
i || si i ^ I
^ °. M ^H" JH 'S S g
C I-H O O t-f
o
i!-s
3
o i) _
1 H * ^
S «i t J
INDEX
Acetylene lamps, 182
Adams portable telephone, 39, 108, 1.10, 130,
11312, 152
Adjustment of heliograph, 174
of ringers, Ii50
Alignment of tree lines, 6*8
Alphabet, International 'Morse, 176
Alternative routes, 2'6
American Army heliograph, 163
Ampere, definition of, 119'
Ardois lanterns, 1'5
Armature, generator, 128
Attachment, split tree insulator, 70
Auger, post-hole, 38>
Bars, digging and tamping, 38
Batteries, dry, types of, 39, 86, 108, 121, ,125
inspection of, 149'
installation of, 85
removal of, 818
renewal of, 87
testing of, 88
Bell, Professor Alexander Graham, l'2'l
Bells, extension, altering tones of, lOli
extension, types of, 39, HOI
used as signals, 15
Belts, linemen's, 37
Books, reference, I'S'S1
Braces, pole, 54
Bracing of poles, 54
Brackets, wood, 37, 50, 52, 70, 74
wood, attachment of, 52
wood, position of, 52
wood, specifications for, 2)18
Branch lines, 8'2
Bridging-bell system of telephone connection,
13(8.
British Army heliograph, 162
Brush method of treating poles, 48
Buffalo grips, 38, 64, 158
Butt-rot in poles, 142, 143.
Buzzer telegraphy, 1)6, 1H31
Cables, lead-encased, properties of, 225
Calls, telephone, list of, 141
Camp management, 3, T2
Capacity, definition of, 131
Carbolineum, 48
Cell, inert, 184
voltaic. 127
voltaic, definition of, 118
Cells, closed circuit, 125
open circuit, 1125
Circuit, definition of, 118
grounded, 28, 32, 60, 90
grounded, connection to metallic, 104, 106
grounded, definition of, '32
light, 32
metallic, 28, 32, 60, 68, 90
metallic, connection to grounded, 104, 136
metallic, definition of, 32
phantom, HO'3, 13'7
power, 32
Clamp, Blackburn ground, 91
Fahnestock test, 82, 14*3
Clamps, ground, types of, 41
Climbers, linemen's, 37
Code, Alphabetical Square, 178
American Morse, 175
International Morse, 115, I'M, 17'5, 193
Myer, 177
ringing, 128, 140
signals, 22
Codes, heliograph, 17'5
message, Ii9'4
Coil, induction, definition of, 119
induction, use of in telephone, 125
telephone induction, inspection of, 1'49
Coils, lavite, 9'8, 159
protection of, 9'8
repeating, 40, 9'8, 10<3\, Ifl5
use of, 9'8
Commissary, 3, '11
Condenser, definition of, 12'0
types of, 4.0
use of, 85, 9i6, 13'1, 1!3'2
use of, in vibratory signalling, 9'6, H32
Conductor, definition of, 118
Connectors, emergency, 11)5
Construction materials, free grant of, 34
Conventional signals, International Morse, 176
Cooking outfit, list of, W9
Co-operative telephone lines, 3'3
Cord, receiver, il-2'3, 149"
receiver, inspection of, 149
Costs, telephone construction, in different types,
28, 201
telephone construction, elements of, 201
Cradle, Mobley wire, 4'©
Creosote, specifications for, 217
use of, 48
Crew, emergency line construction, 75. 7'6
telephone construction, 46, H9'6
Crews, equipment of, 46
Crossing divides, 73
meadows and parks, 7'3
rivers and canyons, 7'3
Crossings, extra long, 78
foreign, 7'8'
high-tension transmission lines, 78
Railway Board .Regulations governing, 203
railway right of way, 78
road, 78
submarine, 80
Cross-talk, 3.2, 62, 142
elimination of, 15«
Crossties, 71, 8-3
Current, alternating, 127, 128
alternating, definition of, 120
difect, definition of, 12/9
Dead-ending, 71, 82, 8*3
Detection of forest fires, 3, 5
Detonations, use of, as signals, 15
" Dont's " in telephone construction, 1'57
in telephone installation, 158
in telephone maintenance, 159
in telephone operation, 15>8
Edison, Thomas 'A., 125
Electric lamps, use of, in signalling, Ii8'3
Electro-motive force, definition of, 1'18
Emergency communication equipment. us.e, of.
227
228
METHODS OF COMMUNICATION FOR FOHKtiT PRO1 'I-:('TIO.\
Emergency lines, connecting to permanent. 7'5
maintenance of, 7>6>
pole setting on, 76
taking up wire on, 76
use of, 74
Emergency telephone kits, types of, 39'
telephone kits, use of, 10-8, 1I1'4
Equipment of construction crews, 4'6
standard list of, >36
Exchanges, private, 8>2
External telephone systems, 24
Fire boss, 1>8
'Fires, forest, detection of, 5
forest, prevention of, 3, 4
forest, suppression of, 7
Fischer high-power lamp, 184
Flags, range of, in signalling, Ii8(6'
speed of, in signalling, li&T
use of in forest protection, 22, 1'87
Flux, 40, 219
Forest protection force, functions of, 3
Forest iService heliograph, I'6i5
Free service on Forestry Branch lines, 35
Frequency, definition of, 120
Fuses, types of, 39
use of, 88, H35
Galvanizing, specifications for, 209
Gauges, wire, names of, IV
wire, comparison of, 222
Generator, electro-magnetic, 120
oiling of, Ii50
telephone magneto, 121, 127
telephone magneto, repairs of, 145, 147
Ground rods, portable, 41
portable types of, 41
Grounds,' 3'2, 9'0
multiple, '9-2
precautions in locating, 91
temporary, 116
Guy rods, 38
Guys, anchor, 55
pole, 54
rock, 57
tree, 56
Hammers, claw, 4.1
Hand set, Adams, 39, liO«, 1-10, 11130, 1,32, 1152
Haven clamps, 38
Haze, effect on range of heliograph, 175
Heliograph, 1160
adjustment of, 1174
American Army, 1160, H6<3, 173
British Army, 1,6-0, 162, 173'
Forest Service, 16>0
Godwin, 160, 1(6*5, H&9
mirrors, I1 6' 9
parts of, 1'6'9
range of, 1'61
screens, 170
sighting-rods, l'7'O
speed of, 161
stations, 21, 160, 165
tripods, 170
use of in forest protection, 21, l'6'O
use of at lookout stations, 165
use of on patrol, 169
Heliographs on towers, 16'8
Heliographing by artificial light, 181
by moonlight, 1-81
with one mirror, 1711
with two mirrors, 172
High-tension lines, interference from, 42, 60,
62, 7'8, 104
protection from, 89, 94, 1134
Hitch, barrel, use of, 76
Holes for telephone poles, digging of, 50
Howlers, 40, 96, 132
use of in vibratory signalling, 9'6
Induction, electro-magnetic, definition of, 119
electro-static, definition of, 120
Insulator, definition of, 1X8
Insulators, glass, specifications for, 2H31
•glass, types of, 37, 52
glass, use of, 27, 74
split tree, attachment of 70, 7|3
split tree, specifications for,. 214
split tree, types of, 37
split tree, use of, 29, 30, 42, 44
strain, 41, 71
Internal telephone systems, 25, 36
Joints, emergency wire, 7'6
insulated wire, 93.
Western Union, 65
Kitchen equipment, list of, 19'S
Knives, electricians', 40'
Lanterns, acetylene, for signalling, 182
electric, for signalling, Is8i3, 184
Fischer high-power, 184
signalling, 182
Lightning arresters, types of, S'91
arresters, use of 88, I'S'S'
danger of, in construction, 60
Linemen, 29
"Listening in," Ii31, 13'2
Location of telephone lines, factors influencing,
42
Lookout men, permanent, in forest protection,
17, 18
stations, 7, 21, 2*6, 36, 7(3, H6'5, I<8i5, 18'7
station telephones, 94
stations, heliograph at, 16'5
Magnet, definition of, 118
Magnets, use of, in generators, 1/28'
use of, in ringers, ll>2!9
Magneto telephone, description of, 117
Materials, emergency line, 74
line, 59, 6'9
standard, list of, 36
Mclntyre sleeves, 38, 6(5
Message codes, 194
Microphone, carbon, 123
Mil, definition of, 121
Mobley wire-cradle, 43 46
Monkey-wrench, 41
Mounting-box, protector, specifications for, 219
Nails, 37
milonite, 40, 94
Numerals, International Morse, 176
Ohm, definition of, 119
Ohm's Law, 111-9'
Open-tank treatment of poles, 48
Operators, heliograph, training of, 180
Pack-frames, Klondike, 45, 46
Mobley, 4i3, 4'6
Packmaster, 10, 18, 19
Party lines, definition of, 1137
Patrol, railway speeder, portable telephone for,
1-09
Patrolmen in forest protection, 18, 21, 2'5.
Permanent forces, direction of, 9
Pigeons, carrier, 14
Pike-poles, 38
Pipes, grounding on, 91
Plans, fire, 9
telephone system, 2'3, 25
Plates, ground, types of 41, 91
Pliers, linemen's, 3'7, 40
I^DEX
229
Pole lines, definition of, 27
Poles, cedar, specifications for, 215
dimensions of, 47
lasting qualities of various species of, 47
number per carload, 221
preservative treatment of, 47
seasoning of, 47
self-supporting, 57
setting of, 52
shortened, re-setting of, 14'5
weights of various lengths and tops, 221.
Pole-steps, 41, 52
•Preservative treatment of poles, 47
Prevention of forest fires, 3, 4
Private telephone lines, 3<3
Protection standards in relation to telephone
lines, 35
Protectors, in fully exposed stations, 89
in partially exposed stations, 89
location of, 89
repair of, 147
telephone, types of, 38
'telephone, types of, 39
Provisions, list of, l'&8
Public roads, use of for telephone lines, 44
Punctuation, International Morse, 1!7'6
Quartermaster, 11, T2, 1>8
Railways, crossing of, 78
Rake, in pole-setting, 50, 52
Receiver, head, 3$
telephone, 121, I'M, 152
telephone, repairs of, 146, 149
Reconnaissance in fire protection, 3, 11
Reel, emergency wire, 38, 75
pay-out, 318, 60
Relay stations, 26*
Repeating coils, 40
Reserves, in forest protection forces, 9
Resistance, definition of, 119
Right of way, clearing of, 44
securing of, 42
Ringers, telephone, 1121, 128
telephone, Ohm resistance of, 2*3, ,1129, 139'
telephone, repairs of, 148, 15'Q, 1'5>2
Roads, crossing of, 7&
Rods, ground., 41, 91
ground, inspection of, 1'47
ground, portable, 11'6
lightning, 39, 52
'Roof ridge of poles, position of, 53
Rules, operating, 140
•Sag allowance, 2.9', 62, 70
distribution of, on pole lines, 6'3
Screw-drivers, 40
•Scouts and scouting in forest protection, 3,
18, 19
Semaphore, fixed, 191
signalling with flags, 188, 19-1
signalling with fixed,, 191
signals, 14
Series system of telephone connection, US'?
Shovels, types of, 3>8
Signalling, buzzer or vibratory, 1113
Signals, audible, 14, H5, 22
chronosemic, 1'4
code, 14
colour, 15
danger, 22, 196
electro-telegraphic, 15
flash, 15
shape, 15
shot, 1.916
visual, 14
whistle, 19)6
.Smoke, effect on range of heliograph, 175
".Smoke chaser," 7, 9, 1'S1, 19, 25
,Solder, 40
Soldering copper, 40
methods and materials-, 219
Spacing of poles, 50
Splicing clamps, 37
wire, 65
Spools, emergency wire, 74, 75, 7'6
emergency wire, specification for, 217
iSpoons, digging, 38
Standards, D. F. B. construction, 60
.Staples, Blake insulated, 40
Static electricity, 15'6
Stations, heliograph, selection of, 173
signalling, 173, 18'8
Strand, galvanized steel, 41, 71
Strategy, fire suppression, 3, 12
Stubs, as pole reinforcements, 143
Submarine telephone lines, 8'0
Supervision, fire-fighting, 3, 8 .
Supervisor, forest, 18, 19, 2<3, 3>4, ,3'5
Supplies, pole-line, 19'7
station, Ii9'.7
tree-line, 19(7
Supports, in forest protection forces, 9
.Suppression, fire, 3, 7
forces, maintenance and direction of, 9
forces, mobilization of, 9
staff officers, 10
Survey of route for telephone line, 42
Surveys, forest, use of signals on, 187
Switchboards, 1011, 135
Switches, 1.31, 13(5, 142
repair of, 147
.Switch-hook, 121, 13<G
inspection of, 147
Tactics, fire suppression, 12
Tamping around poles, 50, 54
Tape, electricians', 40
Telegraph, 20
lines, 32, 78
simultaneous operation with telephone, 106
wireless, 14, 1:6
Telephone, desk set, 38
instruments, types of, 38
lookout-station sets, 94
magneto, description of, 117
portable, 2'5, 3>0, 107. 108
portable, Adams, 3>9, 10'8, 110, 130, 132, 152
portable, Forest Service Special, 39, 108,
1114, 130, 1152
simultaneous operation with telegraph, 106
wall set, 38, 85
wireless, 14, 16
Tension, definition of, 120
Tentage for telephone crew, 198
Test sets, 10'7
stations, 2:6, 142
Ties, regular, 6*3
" figure 8," '6>3, 64, 713, 78
Timber conditions, influence on telephone con-
struction of, 301
Tools, emergency line, 74, 198
linemen's, 37, 46
line-stringing, 3'S, 46, 197
pole-setters, 38, 4'6, 19'7
Torch, soldering, 40
Tree lines contrasted with pole lines, 28
cost of, 2i8, 2'01
definition of, 27
development of methods, 29
Transmitter, telephone, 121. 123
telephone, inspection of, 147
White (qr solid back), 123
230
METHODS OF COMMUNICATION FOR FOREST PROTECTION
Transportation in forest protection, 1,0
Transposition, 32, 62, 6«
Trimmers, tree, 41
Tripods, as line supports, 57
heliograph, 1'69, -170
Trouble, telephone, guide to clearing, 115*3
Trumpet blasts, used as signals, 15
Tubes, porcelain, 40, 92
Tying-in wire, 68
Vibratory signalling, 9<6, 113
Volt, definition of, 118
Voltmeter test-stations, 142
Whistle blasts, used as signals, 15
Wigwag codes, Ifld
signalling with flags, 189
signals, 14
Wire, bimetallic, properties of, 224.
copper, 28, 3'3, 317, 60, '6)1, 81, 8'3, 92
copper, properties of, 223'
copper, specifications for, 2.11
copper, tensile strength of, 223
D. F. B. standard, properties of, 226
emergency, 27, 3'7, 74
emergency, specifications for, 211.
galvanized-iron, 23, 28, 33, 36, 59, 69
galvanized-iron properties of, 224
galvanized-iron, specifications for, 210
galvanized steel, properties of, 225
ground, 9'3
man-packing of, 46
rubber-covered, specifications for, 212
stringing of, 2'9, 60, 7^0
Wiring, inside building, 9'3
outside building, 92
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