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JEFF KELJIK
Electricity 3: Power Generation and Delivery, 10E
Jeff Keljik
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in the United States of America 1 2 3 4 5 6 7 17 16 15 14 13
PREFACE
The tenth edition of ELECTRICITY 3 has been updated to provide more topics and concepts to better reflect the current workplace. At the same time, the text has retained the features and style of previous editions that have made it so popular.
The text introduces the concepts of power generation and distribution. The material is broken down into short segments that concentrate on specific concepts or applications of particular types of equipment. The detailed explanations are written in easy-to-understand language and concisely present the needed information. Many illustrations and photographs help provide technical understanding and real-world references. This type of explanation and application better prepares the student to perform effectively on the job in installing, troubleshooting, repairing, and servicing electrical power generation and delivery.
The knowledge obtained in this book permits the student to progress further in the study of electrical systems. The study of electricity and the application of electrical products are continually changing. The electrical industry constantly introduces new and improved devices and material that lead to changes in installation and operation of equipment. Electrical codes also change to reflect industry needs. It is essential that students continue to learn and update their knowledge of current procedures and practices.
The text is easy to read and the units have been grouped by general subject areas. Summaries in each unit restate the most important topics of the unit. Summaries of unit groupings provide reviews of topical areas.
Each unit begins with the learning objectives. An Achievement Review at the end of each unit provides an opportunity for readers to check their understanding of the material in small increments before proceeding. The problems in the text sometimes require the use of simple algebra. Students should be familiar with the math before trying to solve the equations. It is also essential that readers have a basic understanding of the fundamentals of electrical circuits and basic electrical concepts.
It is recommended that the most recent edition of the National Electrical Code® (published by the National Fire Protection Association [NFPA]) be available for reference and use as the learner uses this text. Application of state and local codes and regulations should also be consulted when making actual installations.
Features of the tenth edition include the addition of a unit on alternative power sources which include wind-powered generation, hydrogen fuel cells, microturbine generation,
and solar photovoltaic power production. These alternative forms of power supplies are described and then linked to the National Electrical Code®, where applicable, to enhance the understanding of where and how these sources are used. An alternate form for a UPS system is described, to be used for short duration operation in place of battery backup systems.
Other features include
• Organization of topics into related topics and associated concepts
• Updated photos and artwork to reflect current equipment and practices
• Content updated to the most recent electrical code
• Additional information on generation systems
• Coverage of transformers and connections
• Summaries and Achievement Reviews at the end of each unit
An Instructor Guide for ELECTRICITY 3 is available. The guide includes the answers to the Achievement Reviews and Summary Reviews and additional test questions. Instructors may use these questions to devise tests to evaluate student learning.
INSTRUCTOR SITE
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ABOUT THE AUTHOR
Jeff Keljik has been teaching at Dunwoody College of Technology in Minneapolis for more than 30 years, where he was the head of electrical programs for more than 16 years. He is a licensed master and journeyman electrician and has a bachelor’s degree in business communication. He currently teaches classes for corporate clients locally and nationally. He also manages the electrical construction and maintenance projects for the college campus buildings at Dunwoody College of Technology. He has worked as an electrician and as a consultant on international training projects in the electrical industry.
In addition to his teaching and administrative positions, Mr. Keljik serves the North Central Electrical League on the Education Committee and as Chairman of the Board of Directors. He also serves as an advisor on the Education committee member for the Minnesota Electrical Association (MEA). He has written several texts on motor and motor control systems and on power generation and distribution, including Electricity 4 and Electric Motors and Motor Controls.
ACKNOWLEDGMENTS
Grateful acknowledgment is given to the following individuals for their contributions to this edition of Electricity 3:
David Adams
Niagara County Community College
Sanborn, NY
Joseph T. Brown
Tri County Technical College
Pendleton, SC
Phillip Serina
Kaplan Career Institute
Brooklyn, Ohio
DEDICATION
I would like to dedicate this tenth edition to my children. Their love of learning encourages me to continue to write texts that help others learn. Jeff Keljik
ELECTRICAL TRADES
The Delmar series of instructional material for the basic electrical trades consists of the texts, text-workbooks, laboratory manuals, and related information workbooks listed below. Each text features basic theory with practical applications and student involvement in hands-on activities.
Electricity 1
Electricity 2
Direct Current Fundamentals
Electrical Wiring—
Electricity 3 Residential
Electricity 4
Electric Motor Control
Electric Motor Control
Laboratory Manual
Industrial Motor Current
Electrical Wiring—
Commercial
Electrical Wiring—
Industrial
Practical Problems
Alternating Current In Mathematics Fundamentals For Electricians
Equations based on Ohm’s law.
P = Power in watts
I = Intensity of current in amperes
R = Resistance in ohms
E = Electromotive force in volts
INTRODUCTION
ELECTRICAL SAFETY
Working on electrical systems can be dangerous. If you are working on live exposed conductive paths and the voltage is over 50 volts to ground, the potential for electrocution exists. The potential for arc burns or explosions also exists when working on live electrical systems. The United States Occupational Safety and Health Administration (OSHA) has specific guidelines to follow when working on live equipment. The OSHA documents that primarily affect practicing electrical workers are found in the OSHA Code of Federal Regulations (CFR) 29–1910. The regulations have many subparts that specify requirements whether you are doing electrical construction or electrical maintenance. In addition to OSHA, the National Electrical Code® refers to the National Fire Protection Association (NFPA) document 70E. This NFPA document was developed by the organization that develops the National Electrical Code® (NEC ®).
NFPA 70E correlates the requirements of OSHA and interprets them for use by electrical personnel. The 70E document is considered a consensus standard, which means governing agencies may adopt or consent to use it as a standard. NFPA 70E and OSHA standards are very similar in intent; 70E interprets the standards in application-related terms. NFPA 70E provides guidelines on safe work practices, information on how to determine arc flash boundaries, and guides on what personal protective equipment (PPE) to use in various situations.
YOUR SAFETY IS YOUR RESPONSIBILITY. Although agencies and organizations try to provide guidelines and practices to follow, it is up to you to be as safe as possible in your work responsibilities. If at all possible, disconnect power from all the circuits with which you will come in contact. You must check for the presence of electrical energy, and then you must lock out the system to prevent accidental re-energization. The term “Lock-Out/Tag-Out (LOTO)” is often used to ensure that you place your personal lock on a disconnection point and then tag it with your name to identify that you are working on the circuit. No one should remove your lock without your knowledge and consent.
There are cases when you will work on systems that are energized. OSHA requires that you have a thorough knowledge of the precautions and procedures to follow. You must have documented training and verification that you are knowledgeable of the dangers involved, you know the precautionary techniques to use, you are aware of the electrocution hazards, and you
understand the hazards of arc flash. You must wear appropriate PPE that has been determined adequate to protect you from the inherent hazards. The PPE includes specifications for the proper clothing and hand and face protection as well as properly rated tools. You must use meters and test gear that accurately test for conditions that are present. You must have a plan to follow if an accident occurs and you need help. There are rules for the number of people who need to be present and there are rules for entering a confined space. Be aware of underground installations and the need for fresh air to breathe. If the environment is hazardous, for example, if gas vapors, dust, or fiber material are present, take further precautions as required.
Arc flash is a danger that is present as you work on live equipment, even if you do not physically touch the conductors with your hands. Electrocution or severe shock may result in contact with the live conductors, but the arc causes damage without contact. The arc that can occur between live parts, or live parts and a grounded surface, releases a great deal of thermal energy. The arc produces magnetic energy and air pressure energy known as the blast. This energy can knock you down or knock the air from your lungs. This same blast creates noise that can damage your hearing. The light produced from the arc may damage your eyesight. The amount of energy that may affect you depends on the type of fault, the amount of short-circuit current available at the arc, the voltage available, and your proximity to the fault. The arc heat energy is rated in calories, and the protective clothing you wear must meet or exceed the number of calories present in a possible arc. Your hands must be protected from accidental contact by using gloves that meet or exceed the voltage rating of the circuit. See the figure showing voltage-rated gloves with leather protection. Your tools must be marked with the voltage rating for the circuit. Voltage-rated tools are pictured in the accompanying figure.
Rubber gloves rated for circuit voltage and leather gloves to protect the insulating qualities of the rubber.
Tools used when working with live electrical circuits have to be electrically insulated and marked with the maximum circuit voltage.
After studying this unit, the student should be able to
• state the function of a direct current (DC) generator.
• list the major components of a generator.
• describe the difference between a separately excited and a self-excited generator.
• explain how the output voltage of a generator can be varied.
A DC generator changes mechanical energy into electrical energy. It furnishes electrical energy only when driven at a definite speed by some form of prime mover, such as a diesel engine or a steam turbine.
DC generators are used principally in electrical systems for mobile equipment. They are also used in power plants supplying DC power for factories and in certain railway systems. DC power is used extensively in communication systems and for battery charging and electroplating operations. The generation of electromotive force (EMF) is described in detail in Electricity 1.
In a DC generator, the output voltage is a DC voltage, even though alternating current (AC) is generated in the generator coils. In other words, one of the output terminals is always negative (−), and the other output terminal is always positive (+). The external circuit is the load connected to the generator. It receives current from the negative terminal of the generator and returns it to the positive terminal of the generator.
DC GENERATOR COMPONENTS
The essential parts of a DC generator are shown in Figures 1–1 and 1–2. The member that spins is called the rotor. The rotor is a cylindrical, laminated iron core that is mechanically coupled to the drive shaft of the generator. An armature winding is embedded in the slots on
MAIN POLE
COMMUTATING POLE
COMMUTATOR
BRUSHES
FIGURE 1–1 Compound generator fields with commutating poles.
OUTER BEARING CAP INSPECTION PLATES
ARMATURE COILS
ARMATURE TOOTH LAMINATIONS
REACTION-TYPE BRUSH HOLDERS
COMMUTATOR ASSEMBLY
COMMUTATOR END BRACKETS
the surface of the rotor. The armature windings have voltage induced into them as the rotor spins past the field poles.
The armature is the component of the generator that has the voltage (EMF) induced into it. The internal circuit of the generator supplies electrons to the negative output terminal of the generator and creates a deficit of electrons at the positive terminal of the generator. The electrons are drawn from the load back to the positive terminal of the generator. The armature is composed of coils of copper conductors that are terminated at the commutator segments. The commutator segments and the connection to the sliding carbon brushes provide the mechanical rectification needed to convert the induced alternating-current EMF within the armature to the direct-current EMF at the carbon brush connections to the load.
A commutator consists of a series of copper segments that are insulated from one another and the shaft. The commutator turns with the shaft and the armature windings. The commutator is used to change the AC voltage induced in the armature windings to DC voltage at the generator output terminals. Carbon brushes pressing against the commutator segments connect the current to the external load circuit.
The armature windings generate voltage by cutting a magnetic field as the armature rotates. This magnetic field is established by electromagnets mounted around the periphery of the generator. The electromagnets, called field poles, are arranged in a definite sequence of magnetic polarity; that is, each pole has a magnetic polarity opposite to that of the field poles
FIGURE 1–2 Cutaway view of a direct-current generator.
FIELD COILS FRAME YOKE
FIELD POLES FAN
adjacent to it. Electrical current for the generator field circuit is usually obtained from the generator itself.
When a generator supplies a current to a load, the current passes through the armature conductors too. As this current passes through the armature conductors, it creates a magnetic field around the armature windings. This magnetic field creates a magnetic influence in the rotor—a counter torque—that opposes the direction in which the rotor is being driven. This is called the “motor effect” of the generator. Figure 1–3 shows that the magnetic field created opposes the driving force. The larger the load current through the generator, the larger the counter torque produced. This is the reason that a generator takes more mechanical power to drive a heavy current load than a light current load.
The armature field flux also reacts against the main field flux and tends to distort it. One result of this undesirable condition, known as armature reaction, is excessive sparking at the brushes on the commutator. To counteract this effect, commutating poles are often inserted between the main field poles, as shown in Figure 1–1. These commutating poles, also called interpoles, are energized by windings placed in series with the output (load) circuit of the generator. Because of this arrangement, armature reaction, which tends to increase with load current, is counteracted by the effects of the load current passing through the interpoles.
FIGURE
Armature reaction, appearing as excessive brush sparking under load, also can be partially corrected by shifting the brushes from their neutral position in the direction of rotation.
Large DC generators have the brushes assembled so that they can be shifted to the position of minimum sparking. When the brushes are not movable, the generator manufacturer inserts other design features to minimize the effects of armature reaction.
Because the magnetic field is distorted by the magnetic action of the armature current in the rotating armature, the neutral plane of the motor is shifted, and the brushes are no longer at the exact center of the magnetic plane. This reaction to the armature current causes the sparking of the brushes. If the load current were always constant, the brushes could be shifted in the direction of rotation until the sparking stops. If the load current is constantly changing, interpole windings are inserted and connected in series with the load to counteract the shifted magnetic field and, in effect, bend it back to its original physical position. When the DC generator is large enough, interpoles are insufficient to counteract the effects of the shift in the neutral plane. Compensating windings are then wound into the pole faces and connected in series with the output current to help move the neutral magnetic plane back to the original physical location.
Another effect of armature reaction is the reduction of the output voltage. As the magnetic field of the rotor (armature) increases because of increased load current, the magnetic field of the rotor tends to cancel some of the magnetic field strength of the main field. This canceling effect tends to decrease the voltage output of the generator.
Brush Polarity
The output terminals of a generator, as with other DC power units, have electrical polarity. In the case of generators, the term brush polarity is used to distinguish between the electrical polarity of the brushes, either positive or negative, and the magnetic polarity, either north or south, of the field poles.
Brush polarity markings are often omitted, but the electrician can easily determine electrical polarity by connecting a voltmeter across the output leads of the generator. Many automotive and aircraft generators are constructed with either the positive or negative brushes grounded to the frame of the generator. It is very important to maintain the polarity as specified by the manufacturer. Additional information on brush polarity is given after the effects of residual magnetism in the field circuit are considered.
Field Supply
The magnetic field of a generator is established by a set of electromagnets (field poles). The current required by the field circuit may be supplied from a separate DC supply. If this is the case, the generator is said to have a separately excited field. The majority of generators, however, are self-excited, and the current for the field is supplied by the generator itself.
Figure 1–4 illustrates a separately excited DC generator with the field circuit supplied from batteries. A self-excited shunt generator is shown in Figure 1–5. Note that the field circuit is connected in parallel with the armature and that a small part of the generator output is diverted to the field circuit to “excite,” or energize, the field poles.
Because the induced voltage into the armature depends on the rate at which the magnetic lines of force are cut per second, it is possible to vary the output voltage by controlling either the speed of the prime mover or the strength of the magnetic field. In all but a few instances, the output voltage is controlled by varying the field current in the field circuit. The flux density in the magnetic field poles depends on the field current. As a result, the field strength and voltage output of the generator continue to increase with an increase of field current until magnetic saturation of the field poles occurs. Any additional increase in voltage output after this point must be obtained by an increase in speed of the rotating armature.
GENERATOR RATINGS
Generator ratings as specified by the manufacturer shall be found on the nameplate of the machine. The manufacturer generally specifies the kilowatt output, current, terminal voltage, and speed of the generator. For large generators, the ambient temperature is also given. See NEC Article 445.11.
ROTATION
A separately excited generator develops voltage for either direction of rotation. This is not true, however, for self-excited units; they develop voltage in one direction only. (See explanation in Unit 3.) The standard direction of rotation for DC generators is clockwise when looking at the end of the generator opposite the drive shaft (this is usually the commutator end).
FIGURE
FIGURE
REGULATION
The voltage regulation of a generator is one of its important characteristics. Different types of generators have different voltage regulation characteristics.
Figure 1–6 shows the action of the voltage at the terminals of a generator for different values of the load current. The drop in terminal voltage is caused by the loss in voltage due to (1) the internal resistance of the armature circuit, including the brush contacts, and (2) armature reaction. The curve at (a) is the normal curve for a shunt generator. An ideal condition is shown in (b), where the voltage remains constant with load current. Curve (c) illustrates a generator with very poor regulation in that the output voltage drops off considerably as the load current increases. A rising characteristic, curve (d), is obtained by using a cumulative compound-wound generator (see Unit 4).
SUMMARY
DC generators are used to provide direct current to specific loads. The armature, mounted on the rotor, is driven through the magnetic poles developed by the electromagnetic fields. AC voltage is actually induced into the armature and then mechanically rectified by the commutator and brush assembly. Brush polarity is established in a self-excited generator by the magnetic polarity of the poles and the direction of rotation. Voltage output is determined by the speed of rotation and the strength of the magnetic field.
Select the correct answer for each of the following statements, and place the corresponding letter in the space provided.
1. A generator ___________________________________________________
a. changes electrical energy to mechanical energy.
b. changes mechanical energy to electrical energy.
c. is always self excited.
d. is always separately excited.
2. One of the following is not essential in generating a DC voltage: ________________
a. a magnetic field
b. a conductor
c. slip rings
d. relative motion
3. Commutating poles are ___________________________________________
a. fastened to the center of the commutator.
b. located midway between the main poles.
c. secondary poles induced by cross-magnetizing the armature.
d. used to regulate the voltage at the armature.
4. The winding on an interpole is ______________________________________
a. made of many turns of fine wire.
b. wound in a direction opposite to that of the armature winding.
c. connected in series with the armature load.
d. connected across the generator terminals.
5. Generator terminals A1 and A2 are terminals that __________________________
a. connect the armature only.
b. connect the shunt field in series with the armature.
c. connect the series field to the armature.
d. have the armature in parallel with the commutating poles.
6. To raise generator voltage, the ______________________________________
a. field current should be increased.
b. field current should be decreased.
c. speed should be decreased.
d. brushes should be shifted forward.
7. Generator voltage output control is usually accomplished by __________________
a. varying the speed.
b. a rheostat in the field.
c. increasing the flux.
d. decreasing the flux.
8. In Figure 1–6, the normal voltage regulation for a shunt generator is at ___________ a. curve (a).
b. a broken line.
c. curve (c).
d. curve (d).
BJECTIVES
2 UNIT SEPARATELY EXCITED DC GENERATOR
After studying this unit, the student should be able to use industry standards to
• explain the relationship of field current, field flux, and output voltage for a separately excited DC generator.
• describe the effects on the brush polarity of reversing the armature rotation and the field current.
• define residual flux and residual voltage.
• draw and explain the basic circuit.
• connect the generator.
The separately excited DC generator has few commercial applications, but knowledge of its operations is an excellent background for understanding other types of generators.
Using a separate source of DC power, S1 is closed, as in Figure 2–1. As DC current flows through the coil of wire wound around the iron core, a magnetic field is produced. The amount of field current is controlled by the resistance of the field winding and the variable resistor, known as the field rheostat. By adjusting the field current, the strength of the magnetic field is controlled. The field flux, or magnetic strength of the magnetic poles, is increased as the field current is increased until magnetic saturation occurs. Saturation of the magnetic field means that no more magnetic flux can be produced even with an increase in field current. The magnetic polarity of the field poles is controlled by the direction of the DC field current and the direction of the wound coils.
The output voltage of the generator is developed as an induced voltage in the armature conductors. This induced voltage appears at the brushes, and the generator output terminals designated as A1 and A2 in Figure 2–1.
To more fully understand the direction of induced voltage, use the left-hand rule for generation, shown in Figure 6–2 in Unit 6. In this figure, the thumb represents the thrust or the direction of the armature movement. The first finger represents the flux direction of the main magnetic field, and the center finger represents the current flow resulting in the armature conductors. Note that by changing the direction of rotation or the direction of the main field flux, the direction of the resultant current flow is reversed.
The output voltage is directly proportional to the speed of the rotation and the strength of the magnetic field. As the speed of the rotor is increased, the output voltage also increases.
FIGURE 2–1 Separately excited DC generator connections.
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JONATHAN TRIMBLERIGG (aged 7) with his Mother & Sister Davidina
Mr. Trimblerigg’s attention was first attracted to the career his elders designed for him, not so much by the habitual goodness with which the rivalry of Davidina had imbued his character, as by his observation of the sensation caused in his native village by the missionizing efforts of a certain boy-preacher, then known to fame as ‘The Infant Samuel Samuel,’ whose call, beginning at his baptism in
that strange invocative reduplication of the family name imposed by his godparents, went on till it suddenly passed in silence to an obscurity from which the veil has never been lifted. What happened then nobody knows, or nobody chooses to tell. But between the ages of seven and fifteen, while sustained by the call, Samuel Samuel never saw a vacant seat, or an uncrowded aisle, or had sitting under him a congregation unrent by sobs in the hundreds of chapels to which the spirit bore him.
When Mr. Trimblerigg heard him, Samuel Samuel at the age of ten was still in the zenith of his powers; and it has been credibly reported that, in the mining villages which he passed through, publicans went bankrupt and committed suicide because of him, and pit-ponies, their ears robbed of the familiar expletives to which they had been trained, no longer obeyed orders; and that alongside of these manifestations of grace, the illegitimate birth-rates went up and struck a record; till, six months later, things settled back and became the same; birth-rates went down, pit-ponies obeyed a restored vocabulary, and ruined publicans were vindicated in the prosperity of their successors.
But these things only happened after; and when Mr. Trimblerigg heard the cry of the Infant Samuel Samuel, he discerned a kindred spirit, and saw a way opening before his feet, under a light which thereafter continued to shine. And so at the age of twelve the designs which Mr. Trimblerigg’s elders had on him, and the designs which he had on himself, coalesced and became one; and even Davidina, borne down by the sense of the majority, had to accept the fact that her brother Jonathan had received a call.
Thus early did the conversion of souls enter into the life and calculations of Mr. Trimblerigg. A striking justification of his chosen calling followed immediately, when, without in the least intending it, he converted an almost lost soul in a single day—the soul of an Uncle, James Hubback by name, the only uncle upon his mother’s side left over from a large family—who while still clinging to the
outward respectability of a Free Church minister, had taken secretly to drink.
Mr. Trimblerigg had been born and brought up in a household where the idea that spirits were anything to drink had never been allowed to enter his head. He only knew of spirit as of something that would catch fire and boil a kettle, or embrace death in a bottle and preserve it from decay. These aspects of its beneficence he had gathered first in the back kitchen of his own home, and secondly in the natural history department of the County Museum, to which as a Sunday-school treat he had been taken. Returning therefrom, he had been bitten for a short while with a desire to catch, kill, and preserve frogs, bats, beetles, snakes, and other low forms of existence, and make a museum of his own—his originality at that time being mainly imitative. To this end he clamoured to his mother to release his saved pennies which she held in safe-keeping for him, in order that he might buy spirit for collecting purposes; and so pestered her that at last she promised that if for a beginning he could find an adder, he should have a bottle of spirit to keep it in.
Close upon that his Uncle James arrived for a stay made sadly indefinite by the low water in which he found himself. He still wore his clerical garb but was without cure of souls: Bethel and he had become separated, and his family in consequence was not pleased with him. Nevertheless as a foretaste of reformation he wore a blue ribbon, and was prevented thereby from letting himself be seen on licensed premises; while a totally abstaining household, and a village with only one inn which had been warned not to serve him, and no shop that sold liquor, seemed to provide a safe environment for convalescence.
It is at this point that Mr. Trimblerigg steps in. One day, taking down a book from the shelf in the little study, he discovered behind it a small square bottle of spirits: he did not have to taste or smell it the label ‘old brandy’ was enough; and supposing in his innocence the word ‘old’ to indicate that it had passed its best use, at once his volatile mind was seized with the notion that here was a mother’s
surprise waiting for him, and that he had only to provide the adder for the bottle and its contents to become his. And so with that calculating larkishness which made him do audacious things that when done had to be swallowed, he determined to give his mother a surprise in return.
Going off in search of his adder and failing to get it himself, he gave another boy a penny for finding him a dead one. An hour later the adder was inside the brandy bottle behind the books; and an hour after that his Uncle James had achieved complete and lifelong conversion to total abstinence.
The dénouement presented itself to Mr. Trimblerigg at first with a shock of disappointment in the form of smashed glass, and his dead adder lying in a spent pool of brandy on the study floor; and only gradually did it dawn upon him after a cautious survey of the domestic situation that this was not as he had at first feared his mother’s angry rejection of the surprise he had prepared for her: on the contrary she was pleased with him. His uncle, he learned, was upstairs lying down, without appetite either for tea or supper. Mr. Trimblerigg heard him moaning in the night, and he came down to breakfast the next day a changed character. Within a year he had secured reinstatement in the ministry, and was become a shining light on the temperance platform, telling with great fervour anecdotes which give hope. There was, however, one story of a drunkard’s reformation which he never told: perhaps because, on after-reflection, though he had accepted their testimony against him, he could not really believe his eyes, perhaps because there are certain experiences which remain too deep and sacred and mysterious ever to be told.
But to Mr. Trimblerigg the glory of what he had done was in a while made plain. More than ever it showed him destined for the ministry: it also gave colour to his future ministrations, opening his mind in the direction of a certain school of thought in which presently he became an adept. ‘The Kingdom of Heaven is taken by tricks,’ became the subconscious foundation of his belief; and when he
entered the pulpit at the age of twenty-one, he was by calculative instinct that curious combination of the tipster, the thimblerigger, and the prophet, the man of vision and the man of lies, which drew to itself the adoration of one half and the detestation of the other half of the Free United Evangelical Connection, eventually dividing that great body into two unequal portions, and driving its soul into a limbo of spiritual frustration and ineffectiveness till it found itself again under new names.
CHAPTER TWO TheEarlyWorm
THOUGH Mr. Trimblerigg had not at the time taken the advice of his Uncle Jonah in very good part, he did eventually accept a large part of it—good or otherwise—in the shaping of his career. His wish to become a great functionary of State gradually faded away, giving place to others. But his intention to be President of the Free Church Conference remained and grew strong. And to that end—spirituality being required—he accepted faithfully Uncle Jonah’s last bit of advice, and seeking a master behind whose back he could hide and be clever in ways that didn’t show—have responsibility taken for his mistakes, and get adequate recognition for the many things which he did right—seeking for such a master, he found him to his own satisfaction in the oldest of old ways; and never from that day on did the suspicion enter his head, that the master whom he chose under so devout an aliaswas himself.
If, in the process, he received a call, so did I; and it was at this stage of his career that I began to watch him with real interest. His calls became frequent; and though there was not always an apparent answer there was always an attentive ear.
It may well be that when human nature appears, to those whose business is to understand it, most unexpected and incalculable, is the very time when it is or ought to be most instructive to eyes which are open. And certainly at this preliminary period—before I got accustomed to him—Mr. Trimblerigg did make me open my eyes wider and wider, till he got me to the point when nothing that he did surprised me. But that was not because I became able to anticipate his reactions to any given circumstance or tight hole in which he might find himself: but merely that experience of him caused me to give up all rules based on the law of averages: he was a law by
himself. What at first baffled me was the passionate sincerity with which he was always able to deceive himself—doing it mainly, I admit, by invoking my assistance: that is to say, by prayer.
To see him fall upon his knees and start busily lighting his own little lamp for guidance through the perils immediately surrounding him— while firmly convinced all the time that the lamp was not his lighting but mine—gave me what I can only describe as an extraordinary sense of helplessness. The passionate fervour of his prayer to whatever end he desired, put him more utterly beyond reach of instruction than a conscious plunge into sin. Against that there might have been a natural reaction; but against the spiritual avidity with which he set to work saving his own skin day by day, no reaction was possible. The day-spring from on high visited him with a lightheeled nimbleness which cleared not only all obstacles of a material kind but all qualms of conscience as well. In the holy of holies of his inmost being self-interest sat rapturously enshrined; there lay its ark of the covenant, and over it the twin cherubim of faith and hope stretched their protecting wings. Mr. Trimblerigg might bow himself in single spirit when first his prayer began; but always, before it ended, his spirits had got the better of him, and he would rise from his knees as beautifully unrepentant as a puppy that has dodged a whipping, his face radiant with happiness, having found an answer to his prayer awaiting him in the direction to which from the first it had been set, much as your Arctic explorer finds the North Pole by a faithful following of his nose after having first pointed it to the north.
I date my completed understanding of Mr. Trimblerigg, and of the use he had made of me, to the day when—faced with an exposure which would have gone far to reduce his ministerial career to a nullity—he put up a prayer which (had I been a mere mortal) would have made me jump out of my skin. I will not skin him retributively by quoting him in full, but the gist of it all was that, much to his perplexity he found himself suffering from a strange temptation, out of keeping with his whole character, and threatening destruction to that life of energetic usefulness in the service of others which he was striving to lead. And so he prayed to be kept (‘kept’ was the
very word)—‘humble, and honest, and honourable.’ It was no change that he desired; but only a continuance in that narrow and straight path of acquired virtue down which (since the truth must be told) he had hitherto danced his way more like a cat on hot bricks, than the happily-banded pilgrim he believed himself to be. ‘Kept’ was the word; and as I heard him I thought of it in all its meanings—and wondered which. I thought of how dead game ‘keeps’ up to a point, and is better in flavour for the keeping; but how, after that point is reached, the keeping defeats itself, and the game is game no longer, but mere offal. Was it in that sense that he wished to be ‘kept’? For certainly I had found him good game, quick in the uptake, and brisk on the wing.
It is difficult in this record to remain consecutive. Those who would follow with accuracy the career of Mr. Trimblerigg, must jump to and fro with the original—one of whom it has to be said that though he denied himself many times (even in the face of the clearest evidence) he denied himself nothing that held out any prospect of keeping his fortunes on the move; and the stitch in time with which he so often and so nimbly saved himself ran in no straight line of machine-made regularity, but rather in a series of diversions this way and that, stepping sideways and back preparatory to the next forward leap; and in this feather-stitching along life’s road he covered more ground, and far more ornamentally, than do those who go merely upon their convictions, holding to one opinion and doing only one thing at a time.
Yet it would be wrong to say that he was ever false to his convictions, for these he seldom knew. Enough that so long as they lasted his intuitions were sacred to him; and as it is the very essence of intuitions that at any moment they may change, his changeableness had about it a sort of truth, of consistency, to which slower minds cannot attain.
But why call it ‘intuition’; why not ‘vision’? Well, if a camera of powerful lens and stocked with highly sensitive films may be said to have vision, vision he had in abundance. Adjusting his focus to the
chosen point of view, he clicked the switch of his receptivity, snapt a picture, wound it off upon its wheel, and was ready for another. In the space of a few minutes he had as many pictures stored as he had a mind for. ‘Vision’? You may grant it him, if you will, so long as you remember that that was the process. I would rather be inclined to call it ‘optics’; and I see his career now rather as a series of optical delusions, through every one of which he remained quite convinced that he was right, and that the truth had come to him by way of revelation. An early example will serve.
The small hill-side village in which Mr. Trimblerigg first learned to escape the limitations of ordinary life was a place where things seldom happened; and there were times in his early upbringing when he found himself at a loose end, a rose wasting its sweetness to the desert air; there was nothing doing in the neighbourhood on which he could decisively set his mark. This was to live in vain; and often he searched through his small world of ideas to find inspiration. Should he run away from home, and be found wandering with his memory a blank? Should he be kidnapped by gipsies and escape in nothing but his shirt? Should a sheep fall into the stone quarry so that he might rescue it, or a lamb get lost in the snow during the lambing-season, that he might go out, and find, and return bearing it in his bosom? Or should he go forth and become famous as a boy-missionary, preaching to the heathen in an unknown tongue? These were all possibilities, only the last suggested any difficulty.
Whenever in doubt, adopting the method of old Uncle Trimblerigg, he turned to the Scriptures: he did not search them, for that would have been self-willed and presumptuous; he merely opened them, putting a blind finger to the spot where divine guidance awaited him. It was in this way that Uncle Trimblerigg had become rich; forty years ago he had invested his savings in house property all through having set thumb to the text, ‘I have builded an house to Thy name.’ And without searching the Scriptures further he had built twenty of them. At a later date, slate-quarrying having started in the district, their value was doubled.
So one day, in a like faith, our own Mr. Trimblerigg committed himself to the same experiment. His first point on opening drew a startling reply, ‘Get thee behind me, Satan, for thou savourest not the things which be of God, but the things which be of men.’ Very right and proper, of course: Satan thus safely disposed of, he tried again. ‘Remember Lot’s wife,’ failed for the moment to convey any meaning; he knew that it could not refer to him: it seemed rather to indicate that his Bible had not yet given him its thorough attention. To warm it to its task he lifted it as a heave-offering, administered to it the oath, as he had seen done in a police court, kissed it, and set it down again. This time it answered sharply, but still not to the point: ‘Ye generation of vipers, who hath warned you to flee from the wrath to come?’ Evidently the Lord was trying him. He turned from the New Testament to the old: perhaps it was only the old he should have consulted, for he had an idea that this was an Old Testament method. That would account for the delay.
The Old Testament made a better response to his appeal. ‘The zeal of Thy House hath eaten me up,’ suggested something at any rate, but did not make the way quite clear; ‘Down with it, down with it, even unto the ground!’ was practical in its bearing upon the Lord’s House, but puzzling; ‘Behold how great a matter a little fire kindleth’ gave him the light he sought.
For at that time Bethesda, the chapel of the Free Evangelicals, had fallen lamentably into disrepair, and since Uncle Trimblerigg, the only man of substance in the district, had retired from the innovation of hymn-singing to a stricter Bethel of his own, there seemed little chance of raising the necessary funds for demolition and restoration. And so decay went on, while still, from old habit, the chapel continued to be insured.
Now whether we call it ‘vision’ or ‘optical illusion,’ there can be no doubt that, thus aided by Scripture, Mr. Trimblerigg visualized rapidly and clearly the means to an end which so many desired. And so it came about one Saturday night, while frost held the village watersupply firmly in its grip, and the road running up from the valley
