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Delmar's Standard Textbook of Electricity, Sixth Edition
Stephen L. Herman
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To my wife , Debb i e, God 's gift to me.
2-10 Ot her Measures of Power
2-11 Ohm's Law
2-12 Metric Prefixes
UNIT3 Static Electricity
3-1 Static Electricity
3-2 Charging an Object
3-3 The Electroscope
3-4 Static Elect ricity i n N ature
3-5 Nuisan ce Static Charges
3-6 Useful Static Charges
UNIT4 Magnetism
4-1 The Earth Is a Magnet
4-2 Permanent M agnets
4-3 The Electron Theory of Magnetism
4-4 Magnetic Materials
4-5 Mag netic Lines of Force
4-6 Electromag netics
4-7 Mag netic Measurement
4-8 Mag netic Polarity
4-9 Demagnet izing
4-10 Mag netic Dev ices
UNITS Resistors
5-1 Uses of Resisto r s
5-2 Fixed Res ist ors
5-3 Co l or Code
5-4 Standard Resistance Values of Fixed Res i stors
5-5 Power Ratings
5-6 Variable Res i stors
5-7 Sche m atic Symbo l s SECTION 2
6-3 Resistance in a Series Circuit
6-4 Calculating Series Circuit Values
6-5 So lving Ci rcuits
6-6 Vo l tage D i viders
6-7 The General Voltage D ivider Fo rmula
6-8 Vo ltage Polarity
6-9 U sing Ground as a Reference
UNIT7
Parallel Circuits
7-1 Parallel Circuit Values
7- 2 Parallel Resista nce Formulas
UNITS
Combination Circuits
8-1 Combinat i on Ci rc uits
8-2 So lving Combination Circuits
8-3 Simplifying the Ci rcuit
UNIT9
Kirchhoff's Laws, Thevenin's , Norton's, and Superposition Theorems
9-1 Kirchhoff's Laws
9-2 Thevenin'sTheorem
9-3 Norton' sTheorem
9-4 The Superposition Theorem
SECTION 3
Meters and Wire Sizes
UNIT 10
Measuring Instruments
10- 1 Analog Meters
10- 2 The Voltmeter
10-3 Multi r ange Vo ltmeters
10-4 Reading a Meter
10- 5 TheAmmeter
10-6 Ammete r Shunts
10- 7 Multi r ange Ammeters
10--8 The Ayrton Shunt
10-9 AC Ammeters
10- 10 Clamp- On Ammeters
CONTENTS
10-11 DC-AC Cl amp -On Ammet ers
10-12 The Ohmmeter
10-13 Shunt-Type Ohmmeters
10-14 Di gital Mete r s
10-15 The Low-Impedance Vo ltage Tester
10-16 The Oscilloscope
10-17 TheWattmete r
10-18 Recording Meters
10-19 Br idge Ci rcuits
UNIT 11
Usi
ng
Wire Tab
l es
and Determining Conductor Sizes
11 - 1 The Amer ican Wire Gauge (AWG)
11-2 Us i ng the NEC Ch arts
11 - 3 Facto r s That Dete r m i ne Ampac ity
11-4 Co rrect ion Factors
11-5 Calculat in g Co nd ucto r S iz es and Resista nce
11-6 Calcu lat i ng Voltage Drop
11 - 7 Parallel Conductors
11-8 Testing W i re Installatio ns
SECTION 4
Small Sources of Electricity
UNIT 12
Conduction in Liquids and Gases
12- 1 The Ionizat ion Process: Magnes i um and Chlo r ine
12- 2 OtherTypes of Ions
12-3 Electroplati ng
12-4 Electrolysis
12-5 Conduction i n Gases
12-6 Ionizatio n i n Nature
UNIT 13
Batteries and Other Sources of Electri city
13- 1 Hi story of the Battery
13- 2 Cells
13-3 Cell Vo ltage
13-4 Primary Cells
13- 5 Secondary Cells: Lead -Acid Batteries
13-6 Ot her Secondary Ce l ls
13-7 Se ries and Paral l el Battery Connectio ns
13-8 Other Sma ll Sources of Electricity
UNIT 14
Magnetic Induction
14-1 Elect romagnet ic In duct i o n
14-2 Fleming ' s Left-Hand Generator Rule
14-3 Mov i ng Magnetic Fields
14-4 Determ i ning the Amount of Induced Vo ltage
14-5 Lenz's Law
14-6 Rise T ime of Current in an Inductor
14-7 The Exponent i al Curve
14-8 In ducta nce
14-9 R-L Time Constants
14-10 Induced Vo ltage Spikes
SECTION 5
Basics
of Alternating Current
UNIT 15
Basic Trigonometry and Vectors
15-1 RightTriangles
15-2 The Pythagorean Theorem
15-3 Sines, Cosines, andTangents
15-4 Formulas
15-5 Practical Applicat i on
UNIT 16
Alternating Current
16-1 Advantages of AC
16-2 AC Waveforms
16-3 Sine Wave Values
16-4 Resistive Loads
16-5 Power in an AC Circ ui t
16-6 Skin Effect in AC Circu its
SECTION 6
Alternating Current (AC) Circuits Containing Inductance 412
UNIT 17
Inductance in AC Circuits
17-1 Indu cta nce
17-2 Induct i ve Reactance
17- 3 Schematic Symbols
17-4 In
UNIT
UNIT
20-10 Nonpolarized Capacitors
20-11 Polar ized Capacito r s
20-12 Variab l e Capacito r s
20-13 Capacitor Markings
20-14 Temperature Coeffic i ents
20-15 Ceram i c Capacitors
20-16 DippedTanta l um Capac itors
20-17 Film Capacitors
20-18 Testing Capacito r s
UNIT21
Ca pacitance in AC Circuits 511
21 - 1 Connecting the Capacitor into an AC Circuit
21-2 Capacit i ve Reactance
21-3 Calculating Capacita nce
21-4 Vo ltage and Current Relationships in a Pure Capacit i ve Circuit 515
21-5 Power in a Pure Capacitive Circuit 517
21-6 Quality of a Capacito r 518
21 - 7 Capacito r Voltage Rating 519
21-8 Effects of Frequency in a Capacitive Ci rcuit 519
21-9 Series Capacitors 521
21 - 10 Parallel Capacitors 524
UNIT22
Resi stive-Capa citive Ser ies Circui ts
22- 1 Resistive -Capacitive Series Circu its
22- 2 Impedance
22-3 Total Cu rrent
22-4 Vo ltage Drop Across the Resistor
22-5 True Power
22-6 Capacitance
22- 7 Vo ltage Drop Across the Capacitor
22-8 Total Voltage
22-9 React i ve Power
22- 10 Apparent Powe r
22-11 Power Factor
22-12 Angle Th eta
UNIT23
Resi stive - Capa citive Parallel Circuits
23-1 Operation of RC Paralle l Circuits
23-2 Calculating Circuit Values
CONTENTS
SECTION 8
AC Circuits Containing Resistance - Inductance- Capacitance 564
UNIT24
Res istive-Inductive - Capacitive Series Circuits
24-1 RLC Series Circ ui ts
24-2 Series Reso nant Circuits
UNIT25
Res istive-Inductive - Capacitive Parallel Circuits
25-1 RLC Pa r allel Circuits
25-2 Parallel Resonant Circui ts
UNIT26 Filters
26-1 Broadba ndTun in g
26-2 Low-Pass Filte r s
26-3 Hi gh -Pass Fil ters
26-4 Bandpass Fil ters
26-5 Ban d-Reject ion (N otch) Filters
26-6 T Filters
26-7 Pl-Type Filters
26-8 Crossover N etworks
SECTION 9 Three-Phase Power
UNIT27 Three-Phase Circuits
27-1 Three -Phase Ci rcuits
27-2 Wye Co n nections
27- 3 De lta Co n nect ions
27-4 Three -Phase Power
27-5 W atts and VA Rs
27-6 Three-Phase Circuit Calculatio n s
27- 7 Load 3 Calculations
27-8 Load 2 Calculatio ns
27- 9 load 1 Calculati o ns
27- 10 A lternato r Calculations
27- 11 Powe r Factor Correction
SECTION 10 Transformers
UNIT28
Single-Phase Transformers
28-1 Single-Phase Transformers
28-2 Iso lation Transformers
28-3 Autotransformers
28-4 Transformer Polarities
28-5 Vo l tage and Current Re l ationships in a Transformer
28-6 Test i ng the Transformer
28-7 Transformer Nameplates
28-8 Determ inin g Maximum Current
28-9 Transformer Impedance
UNIT29
Three-Phase Transformers
29-1 Three -Phase Transformers
29-2 Closing a De l ta
29-3 Three-Phase Transformer Calculations
29-4 Open -Delta Connecti on
29-5 Sing le-Phase Loads
29-6 Closed Delta with CenterTap
29-7 Closed Delta without CenterTap
29-8 Delta-Wye Connect i on with N eutral
29-9 T-ConnectedTransformers
29-10 Scott Connection
29-11 Zig-Zag Connection
SECTION 11
DC Machines
UNIT30
DC Generators
30-1 Wha t Is a Ge n erato r ?
30-2 Armat ure Wind in gs
30-3 Brushes
30-4 Pole Pieces
30-5 Field Windings
30-6 Series Ge nerators
30-7 Sh unt Generators
30-8 Compound Generators
CONTENTS
30-9 Compo un ding
30-10 Countertorque
30-11 Armature Reaction
30-12 Setting the Neut r al Plane
30-13 Paralleling Generators
UNIT31
DC Motors
31-1 DC Motor Princip l es
31-2 S h unt Motors
31 - 3 Series Motors
31-4 Compound Motors
31-5 Terminal Ident ification for DC Motors
31 - 6 Dete rm in ing the Di r ection of Rotation of a DC Motor
31-7 Speed Contro l
31 - 8 The Fie l d -Loss Re l ay
31 - 9 Horsepower
31-10 Brushless DC Motors
31 - 11 Co nverters
31-12 Permanent Magnet Motors
31 - 13 The Right -Hand Motor Rule
SECTION 12
AC Machines
UNIT32
Three-Phase Alternators
32 - 1 Three -Phase A lternators
32-2 The Rotor
32- 3 The Brushless Exciter
32-4 Alternator Cooling
32-5 Frequency
32-6 Outpu t Voltage
32- 7 Paralleling Al t ernators
32-8 Sharing the Load
32-9 Field-Disch ar ge Protection
UNIT33
Three-Phase Motors
33-1 Three -Phase Motors
33-2 The Rotating Magnetic Field
33-3 Connecting Dual -Voltage Three -Phase Motors
33-4 Squirr el -Cage Induct i on Motors
33-5 Wound-Rotor Induction Moto r s
33-6 Synchronous Motors
33-7 Se l syn Motors
UNIT34
Single-Phase Motors
34-1 Sing le-Phase Motors
34-2 Split- Phase Motors
34-3 Resistance-Start Induction-Run Motors
34-4 Capacitor-Start Induction-Run Motors 876
34-5 Dua l -Vo l tage Sp li t -Phase Motors 877
34-6 Determ i ning the Direction of Rotation for Split-Phase Motors 880
34-7 Capacitor-Start Capac itor-Run Motors 881
34-8 Shaded -Pole Induction Motors 883
34-9 Multispeed Motors 887
34-10 Repulsion-Type Motors 888
34-11 Construction of Repulsion Motors 889
34-12 Repulsion -Start Induction -Run Motors 892
34-13 Repulsion-Induction Motors 894
34-14 Sing le -Phase Synchronous Motors 894
34-15 Stepping Motors 896
34-16 Universal Moto r s 903
UNIT35 Harmonics
35-1 What Are Harmon i cs?
APPENDIX A
I dentify i ng the Leads of a Three -Phase, Wye-Co n nected, Dual-Voltage Motor
APPENDIX B
AC Formu las
APPENDIX C Greek Alphabet
APPENDIX D
APPENDIX E
APPENDIX F
Tables 310.15(8)(16), 310.15(8)(17), 310.15(8)(18), 310.15(8)(2)(8), and 310.15(8)(3)(8) are repr inted with perm ission from NFPA 70 -2014® , the National Electrical Cod.P Copyright © 2013, Nationa l Fire Protection Association, Qu incy, Massachusetts 02269. Th i s reprinted materi al i s not the complete and official position of the NFPA, on the referenced subject, which is represented only by the standard in its entirety.
Intended Use
De/mars Standard Textbook of Electricity, 6th edition, is intended fur students in electrical trade programs at high schools and community colleges, as well as chose in industry training. It assumes that the reader has had no prior knowledge of electricity but also provides enough comprehensive coverage to be used as a reference tool fur experienced electricians.
Subject and Approach
The con te nt itself is presented as a blend of the practical and theoretical. It not only explains the different co ncepts relating to electrical theory but also provides many practical examples of how to do many of the common tasks the industrial electrician must perform. An extensive art program containing full co lor photograp h s and line drawings, as well as the inclusion of practical exercises fu r the student, also serve ro further clarify theo retical concepts .
Design ofText
The subject matter has been divided into 35 separate units - each designed to 'stand alone:· The "srand-alone" concept permits the information to be presented in almost any sequence the inst ructor desires, as teaching techniques vary from one instructor t o another The information is also presented in this manner to allow students and instructors quick reference on a particular s ubject.
Math Level
The math level has been kept to basic algebra and trigonometry, and Appendix B contains a sectio n of electrical formulas-all d ivided in to gro ups chat are related to a particular application. Unit 15 of the text provides an introduction to basic trigonom etry and vectors for those students weak in the subject.
A Note about Calculations
De/mars Standard Textbook of Electricity, 6th editi on, like all other scientific texts, contains numerous mathematical equations and calculations. Students ofren become concerned if their answers to problems are not exactly the same as the solutions given in the text. The primary reason fur a discrepancy is the rouncling off of values. Different scientific calculators carry out numbers to different places, depencli ng on the manufacturer and model. Some calculators carry numbers to 8 places, some to 10 places, and some to 12 places. There may also be times when numbers that are reentered into the calculator are carried to only 2 or 3 decimal places of accuracy. For example, the numbers shown below will be multiplied with a calculator chat carries numbers out to 8 places of accuracy: 3.21 x 34.6 x 4.32 x 0.021 x 3.098 x 0.467
The answer is 14.577480.
The same problem will again be multiplied, but th is time each answer will be reentered before it is multiplied by the next number. Each time the answer is reentered, it will be ro unded off to 3 places afrer the decimal. If the !Ourth number afrer the decimal is 5 or greater, the third decimal place will be rounded up. If the fourth number is less than 5, it will be rounded down. The answer is 14.577405.
The same set of numbers will again be multiplied, but this time each answer will be reentered after rounding off the number to one place after the decimal. The answer is 14.617100.
Notice that all three answers are different, but all three are essentially correct. The most accurate answer is 14.577480, and the least accurate answer is 14.617100. Although these answers may look substantially different, they are within approximately 1% of each other.
Another consideration is problems that contain multiple steps. The more steps it cakes co solve a problem, the more chance chere is for inaccuracy. In most instances in this rexr, the answers were left in the display of the calculacor, which perrnics the greatest degree of accuracy. When numbers had co be re-entered, they were taken co 3 places of accuracy. When you work a problem in chis text and your answer is different, consider the degree of difference before concluding that your answer is incorrect.
New to this Edition
The sixth edition of Delmar's Standard Textbook of E lectricity continues to remain true to the comprehensive nacure and visually appealing scyle chat are its trademark fuacures but will now offer more emphasis on the practical approach to electrical theory. New co this edit ion:
Coverage of AC servo motors
• Coverage of AC torque motors
• Updated photographs
Extended coverage of motor nameplate data
Extended coverage ofRL time constants
• Extended coverage ofAC waveforms
"Electrical Occupations" contains information about electrical personnel, building codes, and solar and wind energy
Features ofTheText
"Safety Overview"
At the beginning of Section I, Safety Overview provides information on general safecy rules, personal protective equipment, potential job hazards, lock-ouc/cagout procedures, GFCL Grounding- and more ! Scudents are acquainted with the all important safucy concerns applicable co working in a lab and on the work site.
"Cautions"
Author highlights text where scudents should be aware of potential risks in working with various cypes of electrical equipment.
)\ I>"' : The ammeter, unlike the vo ltmeter, is a very low-impedance device The ammeter is used to measure current and must be connected in series with the load to permit the load to limit the current flow (Figure 10-13).
Math Presentation
Section on vectors in Unit 17 is presented earlier in the text in Unit 15, Basic Trigo· nometry, providing a foundation for students as rhey work through math equations.
"Why You Need to Know"
This element at the beginning of each unit explains to students the importance ofleam· ing the material presented in each unit, and how it may apply to actual job situations.
Single-Phase Motors
"Practical A pplicatio11s"
Word proble ms s re p rh e sruden rs rhrough porendal siruarions o n t h e job a nd e ncourage che m co develop cricic,1] ch inking skills.
PRACTICAL APPLICATIONS
An offitc b1uldins \UC'" .a N.nlt of 6} lnJ·.K1J « lb <onn<ttcd in Mt"fU wilh;, op.aciry o(80 unp•houn <Mh 10 p«i..tdt Nnctyt>ulwpfot tbdr C'OftlP'!kn· The ctlls .:itt to br rcpb«J with h1JnJc cdlJ ..-iih .a ap.irityof 40 How m.uiy ni<ld·mcW h)-dtidt tdl1 .-ill bot ttqulrcd IOl'<f"IJotc the .:iacl how shoo.Id dwyM C'l)t'Ui«'ICJ? •
DVD Correlatio11
Units arc highlighted where mate rial can be viewed on the accompanying DVD ser ies, providing anorher so urce of learning for che student:
DC Electrical Tl>eory, AC Electrical Tl>eory, Si11gle-Pl>aseTra11sfor111ers & Electrical Macl>i11es, Three-Pl.ase Circuits & Electrical MacJ,illes
Text Design
A fresh design c rea res a rexr chat makes it even easier to navigate th rough co nte nt, serving ro focilita re learnjn g for students.
Ne w , Up-to-Date Art
Approximately 110 new fo ur-color photos and lin e ill ustrations combined bring text up co dare, keeping srudcnts aware of th e latest technology in the industq'-
Dedicatio11 to Teclmical Accuracy a11d Comistc11cy
Text was thoroughly reviewed for technical accu racy and con sistency, en s uring existing er rors were co rrected, enabling students ro readily g rasp more diffic ulr co ncepts.
Supplement Package
Lab-Volt Manual provides expe tim ents for srudents co cesr and troubleshoot key concepts presenred in rhe text, using Lab-volt equipment (O rde r #: 978-1- 111 -53916-0)
11>< Complete Laboratory Manual for E lectricity, by Srevc Herman. 111is mamrn.1 is d esign ed co be co nducred w ith co mmon lab equip mcnr. ( Order#: 9 78 -1-133-67382-8)
Instructor Resource (CD-ROM for fostmctors) ( Order #: 978-1 -305-26977-4 )
lnsrructor Guide conta ins a nswers to all review questions and practical applicatio ns co ntain ed \Vi th in the tex t, as \veil as practice exan1s
PoiverPoint prese ntatio ns provide a thorough revie\Y of all rnajor concepts presented in each uni r, fcaniring four-color photos and line illusrracions from die rexc The sixth edition contains num erous Po\verPoint prese ntatio ns. Unit ttstbnnks co ntain a pproximately 700 q uestio ns for instructors to rest s tudent knowled ge as they progress rhrough rhe text. Allows instructors co edir the exa m s and add the ir ow n questions. Image L ibrary consisrs ofall the images from the text in elec tronic for mat, all owing insrrucro rs ro create their O\ vn class roon1 prcsenr:irions.
Instructors Guide & Solutions to Lnb-Volt Manual is in Word format.
To access add.iriona l course materials including Co urscMa te, pl e-.ase visi t \V\V\V .ccngagcbra in.co m At the CengageBrain.com home page, search fo r the ISBN of your ti d e (from ch e back cover of your book) usi ng rhe sea rch box at the top of rhe page. This will tak e you to the product page w h ere these resources can be found.
PREFACE
A DVD Set brings important concepts to life through easy-to-understand explanations and e xamples, professional grap hics and animations, and a necessary emphasis on safery. Videos run approximately 20 minutes The DVDs are inter· active and provide test questions and remediation.
DC Electrica l Theory DV D (4 videos) includes Basic Elect ricity, Series & Paralle l Circuits, Combination Circ uits, and Small Sou rces of E lectriciry.
AC Electrical Theory DVD (5 videos) in cludes Alternat ing Curren t, Inductan ce, Capacitors, Capacitors in AC Circuits, and Series Circuits.
Single-Phase Transform ers & Electrical Ma chines DVD (4 videos ) includes Sin· gle-Phase Transformers; DC Machines; Single-Phase Motors, Part I; Single-Phase Motors, Part II.
Thre e-Phase Circuits & Electrical Machin es DVD (4 videos) includ es Three-Phase Circuits; T h ree-Phase Tra nsform ers; Three-P h ase Motors, Part I; T h ree-Phase Motors, Part II.
Mindtap
M indTap is well b eyo nd an eBook, a h omewo rk solution or digital supplem en t, a reso urce center websice, a course delivery p latform, or a Learning Management System . MindTap is a new personal learning experience that combines all your digital assets- readings, mukimedia, activities, an d assess me nts-into a s ingular learning path to imp rove studen t outco m es.
Instructor Site
A n Instruct or Comp anion website containing s upplementar y ma terial is available. This site con tains an Instructor Guide, an image gallery of text figures, chapter prese ntat io n s d o n e in PowerPoint, and tes ti ng powered by Cognero.
Ce ngage L eaming T esting Po wer ed by Cognero is a .flexible, online sy ste m that allows y ou to:
a uthor, edit, and manage test bank content fro m m ultiple Cengage Learning solutions
• c reate multiple test versions in an instant
• d eliver tes ts from your LMS, you r classroom, or \vherever yo u \Van t
Contact Cengage Learning or your local sales representative to obtain an instructor account.
Accessing an Instructor Companion Website from SSO Fro n t D oor
1. Go to htrp://login.cengage.com and log in using the instructor e-mail address and p asswo rd.
2. E nte r autho r, ti tle, o r ISBN in th e Add a title to yo ur bookshelf searc h.
3. Click Add t o m y booksh elf to add i nstructor reso u rces .
4. At th e Product page, click the Instructor Companio n site li n k
Delmar Online Training Simulation : Electricity
Delmar Onli ne Training S im ul ation: Electric iry is an immersive simulatio n tha t o ffe rs electrical students a learni ng path fr o m bas ic electrical concepts to real world electrical applications It features a variery of engaging simulation activities includ ing interactive wiring diagrams and practical exercises like w iring a lighting branch circu it in a realistic 3D setting.
The interactive ' viring diagrams are visually powerful and illustrate how elcctric iry Bows in a system Students can use a realistic multimeter to measure voltage, amperage, and resistance and rapidly increase their un derstanding of p ractical electrical concepts. There are also exte ns ive animations and tutorials to gradually b uild student confidence with challenging top ics.
Delmar Online I , Tniinlng Simulation F1 ( ( 1 y Cert ain Units in this text will display the Delmar Oni ne Trai ling Simulation: Electlieity ioon at the end of the unit and will speci ty Which modul es in the simulation conta in acti vlll es re l ated to that unit.
The lighting branch simulations are realistic and will give students the practical con· text to understand common electrical tasks. Students will have to choose cab le types and wire inclividual conductors co make the circuits work properly. Circuits include a variety of single pole and 3-way switches.
Printed Access Code ISBN: 978- 1 -305- 26447-2 or Instant Access Code ISBN: 978-1-305-26445-8 availab le for instant p urchase on www.cengagebrain.com.
A Note about the Lab Manuals
The two laboratory manuals, entitled Experiments in Electricity for Use with Lab· Volt EMS E<juipment and The Complete Laboratory Manual for Electricity, 4E, provide extensive opportunities for students ro apply what they have learned. Both manuals contain multiple hands-on experiments for each unit of the textbook and have been extensively field-tested co ens ure that all the experiments will work as planned. The engineers at Lab·Volt condu cted each of the experiments in Experiments in Electricityfor Use with Lab- Volt EMS E<juipment, and, following their testing. Lab-Vole has endorsed this manual. It is the manual they recommend to their customers. The Complete Laboratory Manual for Electricity was field-tested at the Shreveport - Bossier Regio nal Technical School under the clirccrion of Richard Cameron.
About the Author
Stephen L. Herman has been both a teacher of industrial electricity and an industrial elccrri· cian for many years. His formal training was obtained at Catawba Valley Technical College in Hickory, North Carolina. Mr. Herman has wo rked as a maintenance electrician for Superior Cable Corp. and as a class ''l\ electrician for National L iberty Pipe and Tube Co. During those years of experience, Mr. Herman learned to combine his theoretical knowledge of elearicity with practical application. The books he has authored reflect his strong belief that a working electrician musr have a practical knowledge ofbod1 theory and experience to be successful. Mr. Hem1an was the Electrical Installation and Maintenance instructor at Randolph Technical College in Asheboro, North Carolina, fur 9 years. After a return to industry, he became the lead instructor of the Electrical Technology Curriculum at Lee College in Baytown, Texas. He retired &om Lee College after 20 years of service and, at present, res ides in Pittsburg. Texas, with his wife. He continues t o stay active in the industry, write, and update h is books.
Acknowledgments
The author and publisher would like to express thanks to those reviewers who provided insightful feedback thtougllout the development of the sixth eclition of this text:
James Blackett, Thomas Nelson Community College, Hampton, VA
James Cipollone, Antelope Valley Comm unity Co ll ege, Lancaster, CA
Ed uardo Del Toro, MacArthur Hig h School/Independe nt Electrical Contractors, San Antonio, TX
Randy Luclington, Guilford Community College, Greensboro, NC
Robert B Meyers, Jr., Harrisburg Area Comm unity Co llege, Harrisburg, PA
J.C. Morrow, Hopkinsville Community College, Hopkinsville, KY
Larry Pogoler, LA Trade Tech College, Los Angeles, CA
Dean Senter, Pratt Communiry Co llege, Pratt, KS
Justin Shores, Antelope Valley Community College, Lancaster, CA
E lmer Tepper, Gat eway Community College, Phoenix, AZ
Ra ul Vasquez, Independ ent Electrical Co nrracto rs, San Antonio, TX
Electrical Occupations
Organization of the Industry
The electrical industry is one of the largest in the United States and Canada. In 2008, electricians held about 692,000 jobs. Electrical contracting firms employed about 65% of the wage and salaried workers. The remainder worked as electricians in other related industries. About 9% of the electricians were self-employed. The opportunity for employment and advancement as an electrician is one of the highest of any industry. Basically, the entire country runs on electricity. Industry, commercial locations, and homes all employ electricity as the main source o f power. It has been estimated that between 2008 and 20 18 the need for qualified electricians will increase at a rate of about 12%. That represents an annual increase of over 8000 electricians over the next 10 years. The lay· off rate of electricians is one of the lowest of any occupation. If industry operates, it will require electricians to keep it running.
Electrical Personnel
Electricians can generally be divided into several categories, depending on their specific area of employment. Each of these categories may require special skills.
Constr<u:tion
Electricians working in the construction industry generally require a basic knowl· edge of electrical theory and an extensive knowledge of National Electrical Code• requirements and wiring practices. Electricians in the construcrion area can generally be divided into helpers, journeymen, and masters. Many states require tests for journeymen and master levels.
Industrial Electricians
Industrial electricians are generally concerned with maintaining equipment that has already been installed. Electricians in an industrial environment require an extensive knowledge of electrical theory and National Electrical Code• requirements for installation of motors, capacitor banks, and transformers. Industrial electri· cians should also possess a basic knowledge of electronics and electronic devices. Modern industry employs many electronic devices, such as variable frequency drives, solid state controls for direct current motors, and programmable logic controllers. A.nother area of concern for most industrial electricians is motor controls. Motor control systems are generally either relay logic or electronic in the form of programmable logic controllers or distributive control system s.
Instrumentation Technicians
Instrumentation technicians calibrate and maintain devices that sense such quanti· ties as temperature, pressure, liquid level, flow rate, and others. These people should have an extensive knowledge of electrical theory, especially as it pertains to low· voltage and closed-loop systems.
Related Industries
The fields related to the electrical industry are coo numerous to mention but include air conditioning and refrigeration, aircrafr electronics, automotive, cable TV, broad· cast media, energy and utilities, and home appliance and repair, as well as many, many others. The opportunity for employment in the electrical field is almost unlimited.
Union and Nonunion Employees
The largest percentage of electricians are nonunion empl oyees. Many construction electricians receive training at various trad e and technical schools Some employers also sp onsor appren tices h ip p rograms. Appre nticeship •type programs generally require the electrician to wo rk o n the j ob as well as attend classes. The advantage to apprenticeship training is that it perm its a p erso n to earn money while he or sh e attends cl ass T h e disadvantage is that it can c rea te an ex treme ly b usy schedule Mos t ind ustrial e lectrician s, and those in related fields, require special train ing at a trade or technical school.
The largest electrician's u nion is the International Brotherhood of Electrical Worke rs (!BEW). The con str uction electric ians wh o belong to th e !BEW generally receive apprenticeship - type training for an organization called the National J oint App rentices hip Training Co m m ittee (NJATC) . Un ion electricia ns w ho work in related fields generally belon g to un ions organized for their p articula r in dustry, su ch as U nited A uto Workers or United Steel Workers
Apprentices, w h ether unio n or nonunio n, a ttend classes several hours a week and wo rk on the j ob unde r th e supe rvision of a j o urneym an . Most j o u rneymen h ave completed their apprenticeship training and a set number of hours of practical work, and are required to pass an exan1ination to become a journeyma n. J ourneymen work u nder the s uperv ision of a maste r electrician. The master is ultimately responsible for the work performed and is answerable to the architect or owner. Most states require not only that a master pass a very rigorous exan1in atio n b u t also be bonded for a particular sum of money, depending o n the s ize of the j ob he or s h e bids o n
Ethics
Probab ly the greacestdocument concerning ethical behavior was given to a man named Moses on top of a mo untain several th ousand years ago and is call ed the Ten Com mandments. Ethics a re th e p ri n cip les by w h ic h behavio r is j udged t o be right or wrong. T h ere is an old saying stating that d1e best advertisement is word of mouth. TI1is type of advertisement, however, can be a two-edged sword Peop le who do poor wo rk, c h arge fo r wo rk th at was not don e, make promises that are neve r kept, and cheat people at every op portunity gain a rep u tation t hat eve ntually catches up wi th them .
Peop le wh o do an h o n es t day's work for an h onest wage, keep promises, an d deal fairly with other people gain a reputation that will lead co success. Many years ago I worked for a man who had a business of rebuilding engines. He charged abo ut twice the going rate of any o th er pe rson in t ow n and had more business than h e could h andle. I o nce ask ed h im h o w h e co uld charge more than anyone else and still have m ore business than anyo n e else. His answer was simple. He said, "There are two ways by which a business can b e known. O ne is as t he c h eapest in town and the other is as the best in town . I'm the best in town:' Most people are willing to pay mo re for a person that has a reputat ion for doing quality work and dealing honestly with customers.
Appearance
Appearance p lays a majo r role in how a person is perceived. The old sayin g th at first impressions are the most important is true. This doesn't mean that fo rmal office artire is req uired t o make a good impression on a prospective cus tomer, but a professional person is expect ed to look profess ional. A p erso n wh o wea rs clean work clo thes and d rives a re la tively clean vehicle makes a much better impression than someone who shows up in filthy clothes with shirttail hanging out and pants sagging almost to the knees
Communication
Communication skills are extremely important on any job. These skills can be divided into several areas such as speaking, listening, and writing.
Speaking: Speaking well is probably one of the most important skills for obtaining a successful career in any field. Generally, one of the first impressions you make concerns your ability to speak properly. Even though slang is widely used among friends, family, and the media, a person who u ses proper E nglish gives th e imp ression of being ed ucated, informed , and professional.
The ability to speak also involves communicating with people on the job, whether that person is a j ourneyman or an e mployer. The ability to explain clearly h ow a job was done or why it was done a certain way is also importanr, as it is often necessary to communicate with people who have no knowledge of the electrical field. The ability to explain to a homeowner why a receptacle or switch should o r should not be placed in a particular location is important
Listening: Listening is probably the most understated skill concerning communication You should nor only lis ten to what a person wants bu t also make s ure you understand what he or she is saying. Not understanding what a p erson wants can lead to extremely costly mistakes . The most costly work is that which has to be redone because of a misunderstanding An exam· p ie of how misunderstandings can lead to costly mistakes is shown in Figure Occupations 1
Writing: Many j obs require the electrician to fill out work reports char can include a description of the job, the materials used, and the time required to complete the job. This is especially true of a p erson in charge of other workers, s uch as a j ou rneyman.
Maintenance electricians in an indust rial e nvironment ge ne rally submit a repo rt on the maintenance performed on a particular machine. The report commonly includes the particular machine, the problem encountered, the materials necessary for repair, and the time spent in troubleshooting and repair.
Working on a Team
Teamwork is essential on most construction jobs The typical construction job may include people that pour the concrete foundation; carpe nters; brick masons; stone masons; plumbers; landscapers; people that install floo ring and carpet; air-conditioning and refrigeration contractors; and, of course, electricians. One of the key elements to a successful ream effort is communication. If cond uit is to be run under the s lab, it is better to comm un icate with the people doing the foundatio n and inform the m that conduit n eeds to be run before the slab is poured.
Be respectful of other trades If an electrical outlet box is in the way of a sewer line, the plumber may ask that it be moved. It is much easie r co move an outlet box than it is
to reroute a sewer line. If electrical boxes are to be placed in an outside brick wall, ask the brick mason how he would like the box to be placed. A little respect for other trades plus communication can solve many problems before they happen. If possible, help other people. If you are already in an attic and the air-conditioning contractor asks whether you would be willing to do a small job that would save him rime and effort, it is good working relations to do so. Grudges and hard feelings do not happen in a work setting where kindness is practiced.
Building Codes
Many cities, coun ties, and states have their own building codes that supersede the National Electrical Code". The National Electrical Code• is law only if the local authority has adopted it as law. Always check local codes before beginning a construction project. Local codes often specify the manner in which wiring is to be installed and the size or type of wire that must be used for a particular application.
Green Building
"Green building'" basically means making buildings more energy efficient. This can encompass many areas of the construction such as using'"low E'" energy-efficient windows, adding extra insulation, adding so lar collectors to assist the water heater, and installing solar panels and/or wind generators to assist the electrical service. For the electrician, it may be installing larger wire than necessary to help overcome voltage drop, or installing energy-efficient appliances such as heat pump-type water heaters. These water heaters use about half the amount of power of a standard electric water heater. Energy-efficient appliances are generally idencined by an Energy Star label. Energy Star is a government· backed symbol awarded to prod ucts that are considered energy effic ient. Energy Star was established to reduce greenhouse gas emissions and other pollutants caused by inefficient use of energy, and to aid consumers in identifying and purchasing energy-efficient products that will save money without sacrificing performance, features, or comfort.
Before a product can receive an Energy Star label, it must meet certain requirements set forth in Energy Star produce specifications:
Product categories must produce significant energy savings nationwide.
Qualified products m ust deliver the features and performance demanded by customers as well as increase energy efficiency.
If the qualified product cost more than a conventional, less-efficient counterpart, purchasers must be able to recover their investment in increased energy efficiency through utility bill savings, w ithin a reasonab le period of time.
Energy efficiency must be achievable through broadly available, nonproprietary tech· nologies offered by more than one manufacturer.
Product energy consumption and performance must be measurable and verified with testing.
Labeling should effectively differentiate produces and be dearly visible to purchasers.
Solar Energy
One of the primary sources ofgreen energy is solar power. Solar energy is the primary source of heating water in many countries and can be as simple as a dark colored container mounted on the roof of a structure, Figure Occupations 2. Other type.< of so lar water heaters involve a
FIGURE OCCUPATIONS 2 Solar water heaters mounted on a roof.
solar collector, a special rank that contains a h ear exchanger, and related equipment, Figure O"upation5 3. Most of these types of water h earers contain backup electric heating elements fo r cloudy weather when th e solar collecto r cannot s upp ly eno ug h energy to heat the wate r
So me sola r syste ms gene ra te elec tricity and are generally called PV (p hotovoltaic) systems . In these types of systems solar panels are mounted on the roof of a dwelling or in an ope n area on the ground, Figure Occupations 4 . Photovoltaic cells generate direct current, which must be changed i nto alternatin g cutrent by an inverter, Figure Occupations 5. The home remains conn ected to the utility company at all times The solar panels augment the inco ming power to h elp red u ce th e en ergy supp lied by the utility company. There are vario u s me th od s of supplying p owe r to th e utility company, dep ending on the requirements of the utility company and state laws. Some systems cause the electric meter to run backward during times that the so lar panels are producing more energy than is being s up· plied by the u tility comp any. Other systems require rh e use of two separate meters, Figure Occupations 6. One records the amount of power supplied by the u tilicy company a nd the o ther records the a mount o f p ower s upplied b y the solar cells The utility compan y t hen purchases the power from the homeowner or in some cases gives the homeowner credit for the amount of power generated. Other systems employ batteries to store the electricity produced by the so lar p anels An uninterrupt able power supply (UPS) co nver ts the direct cur re nt in to alternating current. In th e event of a p ower failure, the UPS conti nues to supply power from the storage batteries.
T h e amou nt of electricity produced by the sol a r panels is direc tly proportional to the intensicy of sunlight striking rhe panels. The graph shown in Figure O"upations 7 illustrates the power output over a 24-hour period. The information was gathered during the m onth of March. Solar ce lls have a very long life span, ge nerally con sidered to be
FIGURE OCCUPATIONS 3 Some sola r water heaters use a so lar panel and special ta nk with a heat exchanger.
FIGURE OCCUPATIONS 4 Solar pa nels are often mou nted on the roof or in an open area
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of a lack of occupation. It is difficult for him to accept the fact that the most notable sight in Mexico is simply Mexico.
It is difficult, too, for him to reconcile the general outward conditions of the towns and cities with his preconceived ideas of them, which is always annoying. Instead of giving an impression of dirt and neglect, of the repulsive indifference to appearances, and general “shiftlessness” we are so accustomed to in the small communities of States like, for instance, Arkansas and Indiana, their best quarters always, and their more modest districts very often, are perpetually swept and sprinkled, dazzling with new calcimine and, for thoroughfares so aged, incredibly neat and gay. About drainage and water works—the invisible and important—there is still much to deplore, much to hope for, although improvement is everywhere on the way. But municipal “appearances” are rigidly maintained; maintained in some instances at the cost, unfortunately, of qualities that share the secret of the country’s charm. There is at the present time, for example, a rage—a madness rather—for renovating, for “doing over” the exteriors of churches, and in the last four years some of the most impressive examples of Spanish colonial church architecture have been scraped, punctured with pointed windows, supplied with gargoyles and porticoes and then whitewashed. To remember the cathedral at Jalapa as it was, and to see it now, a jaunty horror half clad in cheap, Gothic clothes that don’t fit, brings a lump to one’s throat.
The order and security that everywhere appear to reign both by day and by night are also bewildering in a country popularly supposed to be the modern fountain-head of lawlessness and melodrama. Besides the small but businesslike policemen with large, visible revolvers who seem to be on every corner and who materialize in swarms at the slightest infringement of the code, the highways are patrolled by that picturesque body of men known as rurales, of whom there are between four and five thousand. After the fall of Santa Anna, the organized troop of ranchmen (known as “cuerados” from the leather clothes they wore) became bandits and gained for themselves the name of “plateados,” it being their dashing custom heavily to ornament their garments with silver. In the time of Comonfort they were turned from their evil ways (no doubt on the theory of its taking a thief to catch a thief) and transformed into rurales. Under President Diaz they have attained a high degree of efficiency, and while their practically limitless powers in isolated and inaccessible parts of the country are no
doubt sometimes abused, their reputation for fearlessness, supplemented by a revolver, a carbine, and a saber, has a most chastening influence. One realizes something of the number of policemen at night, when they deposit their lighted lanterns in the middle of the streets and there is until dawn a ceaseless concert of their wailing whistles. You may become as drunk as you wish to in a cantina and, even with the doors open, talk as loud and as long as you are able, for cantinas were made to get drunk and talk loud in. But you must walk quite steadily when you come out—unless your wife or daughter is laughingly leading you home—or you will be arrested before you reel ten yards. Even chaperoned by your wife and unmistakably homeward bound, you will be escorted kindly, almost gently (when you show no resistance), to the police station if the city happens to need your services. The combination of quick temper and quicker drink is responsible for much violence in Mexico, but one rarely sees it. One rarely sees any form of disorder, and over vice is draped a cloak of complete invisibility. In most places women of the town are not even permitted to appear on the streets except at certain hours and in a capacity sincerely unprofessional. The facility and dispatch with which one is arrested is conducive to a constant appearance of decorum. Only in a paternal despotism is such law and order possible. One evening I myself was arrested for an exceedingly slight and innocent misdemeanor.
“But why do you arrest me? Why don’t you arrest everybody else? I’m not the only one,” I protested to the policeman with a lightness I was beginning not to feel.
“You are a foreigner and a gentleman and you ought to set an example to the ignorant lower classes,” he replied without a smile. It was some time before I could induce him to let me go.
The frequency of the policemen is equaled (or exceeded, one sometimes feels) only by the frequency of the churches. And, as if there were not already thousands more than the souls of any people could possibly need, new ones are always being built. I was told not long ago of a wealthy man who, on recently acquiring a vast area of land which he contemplated turning into a sugar hacienda, began the construction of his “plant” with a thirty-thousand-dollar church. Their number and the manner in which they monopolize all the most conspicuous sites, as well as render conspicuous most of the others, now and then enables even a Roman Catholic to regard the Laws of Reform with a slightly less bilious eye. The countryside is
dotted with them—the towns and cities crowded by them. It seems at times as if the streets were but so many convenient lanes through which to approach them—the shops and houses merely so many modest dependencies. Pictorially considered, they imbue the dreariest, most impersonal of landscapes, especially just after sunset, with a mild and lovely atmosphere of human pathos that one might journey far without seeing again. But even in Mexico the pictorial sense is subject to periods of suspended animation during which one’s attitude toward the churches, or perhaps I should say the Church, is curiously ill-defined. It is discomposing, on the one hand, to learn of a powerful bishop whose “wife” and large family of sons and daughters are complacently taken for granted by his entire diocese—to be warned by a devout Catholic never under any circumstances to allow one’s American maid servants to converse with a priest or to enter his house on any pretext whatever—to appreciate the extreme poverty of the people and to realize that the entire gigantic corporation is kept running chiefly by the hard-earned mites with which they hope to save their souls. In the church of San Miguel (not a particularly large church) at Orizaba, I once had the curiosity to count the various devices by which the faithful are hypnotized into leaving their money behind them, and as I made notes of the little alms boxes in front of all the chapels, at the doors, and scattered along the nave, many of them with a placard explaining the use to which the funds were supposed to be put, I could not but admire the unerring instinct with which the emotions of the race had been gauged. The system, assisted as it is by a fantastically dressed lay figure at every placarded box, has for the population of Orizaba (an excessively religious town) much the same fascination that is exercised upon me by a penny arcade. There were boxes for “The Monthly Mass of Jesus,” “For the Marble Cross,” “For the Sick,” “For the Sick of S. Vincent and S. Paul,” “For Mary Conceived without Sin,” “For Our Father Jesus Carrying the Cross,” “For Saint Michael,” “For the Blessed Souls,” “For the Blessed Virgin,” “For Our Lady of Carmen,” and then, as if the ground had not been tolerably well covered, there were two boxes, “For the Work of this Parish.” But these were literally less than half the total number. In addition to the twelve whose uses were revealed, there were eighteen others whose uses were not, or thirty in all.
On the other hand, I cannot linger in Mexican churches day after day, as I have done, watching the Indians glide in, remove the leather bands from
their foreheads, let their chitas slip gently to the pavement, and then, with straight backs and crossed hands, kneel in reverent ecstasy before their favorite images, without rejoicing that a profound human want can be so filled to overflowing. And I cannot but doubt that it could by any other way we know be filled at all. Three men in Indian white, who are returning from market to their homes in some distant village, stop to kneel for fully half an hour without moving before the chapel of St. Michael. St. Michael happens to be an almost life-sized female doll with pink silk socks, the stiff skirts of a ballet-dancer (actually), a pink satin bolero jacket, an imitation diamond necklace, a blond wig with long curls, and a tin helmet. The two women who accompany them pray before the figure of Mary Conceived without Sin—whose costume I prefer not to invite the accusation of sacrilege by recording. The men are straight-backed, motionless, enthralled. One of the women suddenly extends her arms with an all-embracing gesture, and rigidly holds them there—her hands palm upward, as if she expected to receive the stigmata. What are they all thinking about? But what earthly difference does it make—if there be a difference so heavenly? No doubt they are thinking of nothing; thought is not essential to bliss. Then they get up, and after dropping money in the little slot machines of Michael, and Mary Conceived without Sin, they proceed on their way, leaving me glad that for fully half an hour some one in the world has been happy. For beyond the possibility of a doubt they have been happy, and have deepened my conviction that the desire to undermine their faith in Michael and in Mary Conceived without Sin is at best misguided, and at worst, wicked. “Idolatry and superstition!” one hears groaned from end to end of Mexico. But why not? They appear to be very comforting, exalting things. It happens that personally I could derive no spiritual refreshment from remaining on my knees for half an hour in front of these dreadful dolls. But there is a statue or two in the Louvre, and several pictures in Florence, to whom—had I been brought up to believe them capable of performing miracles—I should find it most agreeable and beneficial to say my prayers.
So one’s attitude toward the Church in Mexico becomes at the last curiously ill-defined. The Church is corrupt, grasping, resentful; but it unquestionably gives millions of people something without which they would be far more unhappy than they are—something that no other church could give them.
There are city parks and squares in other countries, but in none do they play the same intimate and important part in the national domestic life that they do in Mexico. To one accustomed to associate the “breathing spaces” with red-nosed tramps and collarless, unemployed men dejectedly reading wilted newspapers on shabby benches, it would be impossible to give an idea of what the plaza means to the people of Mexico—of how it is used by them. It strikes me always as a kind of open-air drawing-room, not only, as are our own public squares, free to all, but, unlike them, frequented by all. It is not easy to imagine one’s acquaintances in the United States putting on their best clothes for the purpose of strolling around and around the public square of even one of the smaller cities, to the efforts of a brass band, however good; but in Mexico one’s acquaintances take an indescribable amount of innocent pleasure in doing just this on three evenings a week and on Sunday afternoons as well. And with a simplicity—a democracy—that is a strange contradiction in a people who have inherited so much punctilio— such pride of position, they do it together with all the servants and laborers in town. In the smaller places the men at these concerts promenade in one direction, while the women, and the women accompanied by men, revolve in the other; a convenient arrangement that permits the men to apperceive the charms of the women, and the women to apperceive the charms of the men without effort or boldness on the part of either. And everyone is socially so at ease! There is among the rich and well dressed not the slightest trace of that “certain condescension” observable, I feel sure, when the duke and the duchess graciously pair off with the housekeeper and the butler, and among the lower classes—the maid and men servants, the stonemasons and carpenters, the cargadores, the clerks, the small shopkeepers— there is neither the aggressive sense of an equality that does not exist nor a suggestion of servility. The sons of, say, the governor of the state, and their companions, will stroll away the evening between two groups of sandaled Indians with blankets on their shoulders—his daughters in the midst of a phalanx of laundresses and cooks; the proximity being carried off with an engaging naturalness, an apparent unawareness of difference on the part of everyone that is the perfection of good manners. When such contacts happen with us it is invariably an experiment, never a matter of course. Our upper classes self-consciously regard themselves as doing something rather quaint—experiencing a new sensation, while the lower classes eye them with mixed emotions I have never been able satisfactorily to analyze.
But the serenatas are the least of it. The plaza is in constant use from morning until late at night. Ladies stop there on their way home from church, “dar una vuelta” (to take a turn), as they call it, and to see and be seen; gentlemen frequently interrupt the labors of the day by going there to meditate over a cigar; schoolboys find in it a shady, secluded bench and use it as a study; nurse maids use it as a nursery; children use its broad, outside walks as a playground; tired workmen use it as a place of rest. By eleven o’clock at night the whole town will, at various hours, have passed through it, strolled in it, played, sat, rested, talked, or thought in it. It is the place to go when in doubt as to what to do with oneself—the place to investigate, when in doubt as to where to find some one. The plaza is a kind of social clearing house—a resource—a solution. I know of nothing quite like it, and nothing as fertile in the possibilities of innocent diversion. Except during a downpour of rain, the plaza never disappoints.
I have grown rather tired of reading in magazines that “the City of Mexico resembles a bit of Paris”; but I have grown much more tired of the people who have also read it and repeat it as if they had evolved the comparison unaided—particularly as the City of Mexico doesn’t in the least resemble a bit of Paris. It resembles absolutely nothing in the world except itself. To criticise it as having most of the objectionable features and few of the attractions of a great city would be unfair; but first telling myself that I am unfair, I always think of it in those terms. In truth it is a great and wonderful city, and it grows more wonderful every day; also, I am inclined to believe, more disagreeable. Unfortunately I did not see it until after I had spent six months in Mexico—in Vera Cruz, in Jalapa, in Orizaba, in Puebla, in the depths of the country—and when it finally burst upon me in all its shallow brilliancy, I felt that I was no longer in Mexico, but without the compensation of seeming to be somewhere else. I certainly did not seem to be in Paris. The fact of going to a place for no reason other than to see what it is like, always stands between me and a proper appreciation of it. It does, I think, with everyone, although it is not generally realized and admitted. A certain amount of preoccupation while visiting a city is essential to receiving just impressions of it. The formation of judgments should be gradual and unconscious—should resemble the processes of digestion. I have been in the capital of the republic half a dozen times, but I have never, so to speak, digested it; I have merely looked without losing consciousness
of the fact that I was looking, which is conducive to seeing too much on the one hand, and on the other, too little.
After the jungle and the smaller places, the city impressed me, on arriving at night, as wonderfully brilliant. There were asphalted streets, vistas of illuminated shop windows, enormous electric cars, the inviting glow of theater entrances, a frantic darting of cabs and automobiles, and swarms of people in a strangely un-Mexican hurry. The noises and the lights were the noises and the lights of a metropolis. Even daylight did not, for the first morning and afternoon, have any appreciable effect upon the general sense of size and effulgence. But somewhere within forty-eight hours the place, to a mere observer, began to contract—its glitter became increasingly difficult to discern. It was not a disappointment exactly, but neither was it “just like a bit of Paris.” It remained extremely interesting— geographically, historically, architecturally—but it was oddly lacking in the one quality everybody is led to believe it has in a superlative degree. Without doubt I shall be thought trifling to mention it at all. In fact I don’t believe I can mention it, as I don’t precisely know what it is, and the only way in which I can hope to make myself even partly clear will sound not only trifling but foolish. I mean—the City of Mexico lacks the indefinable quality that makes one either desirous of putting on one’s best clothes, or regretful that one has not better clothes to put on. To dear reader this may mean something or it may not. For me it instantly recreates an atmosphere, recalls certain streets at certain hours in New York, in Paris, in London—in a few of the less down-at-the-heel, Congoesque localities of Washington. One may or may not possess the garments in question. One might not take the trouble to put them on if one did. But the feeling, I am sure, is known to everyone; the feeling that in some places there is a pleasantly exacting standard in the amenities of appearance which one must either approximate, or remain an outsider. In the City of Mexico one is nowhere subject to such aspirations or misgivings, in spite of the “palatial residences,” the superb horses, the weekly display of beauty and fashion. For the place has upon one—it has at least upon me—the effect of something new and indeterminate and mongrel, which for a city founded in 1522 is a decidedly curious effect to exert.
It arises without doubt from the prosperity and growth of the place—the manner in which it is tearing down and building up and reaching out— gradually transforming whole streets of old Spanish and Mexican houses
into buildings that are modern and heterogeneous. In its center, some five or six adjacent streets appear to have been almost wholly so converted, the final proof of it being that in front of the occasional elaborately carved old doorway or armorial-bearing façade and castellated top, one instinctively pauses as in the presence of a curiosity. Imbedded as they are in unusually unattractive quarters of purely native origin, these half a dozen business streets suggest a small city in the heart of a large town. They might, one feels, be somewhere in Europe, although the multitude of American signs, of American products, and American residents, by which one is on all sides confronted, makes it impossible to decide where. There is a surprising transformation, too, on the left of the Paseo, along the line of the electric cars on the way to the castle of Chapultepec. (A lady in the throes of displaying an interest in Mexico exclaimed to me the other day: “There have been so many earthquakes in Mexico of late that I suppose Chapultepec is very active!”) The bare, flat territory is growing an enormous crop of detached dwellings that seek to superimpose Mexican characteristics upon an American suburban-villa foundation, with results not always felicitous. Outwardly, at least, much of the city is being deMexicanized, and whereas the traveler, to whom it has been a gate of entrance, has eyes and adjectives only for its age, its singularity, its picturesqueness (all of which are indisputably there), the traveler who sees it last—for whom it is an exit—is more inclined merely to be discomposed by its uncompleted modernity.
For, not unreasonably, he expects to find there some of the frills of civilization; luxurious hotels, “smart” restaurants, an embarrassing choice of cafés and theaters. Such frills as there are, however, succeed for the most part in being only pretentious and ineffective, like those a woman tries to make at home after taking notes in front of a milliner’s window. The leading hotels are all bad—not in the sense of being uncomfortable, for they are comfortable enough, but in the sense of purporting to be something they are not. The four I have stayed in reminded me of a placard I once saw while endeavoring to find something edible at a railway “eating house” in one of our Western States. “Low Aim, not Failure is a Crime,” the thing declared with an almost audible snigger. Surrounded by the second-and third-rate magnificence of the capital’s best hotels, one longs for the clean, native simplicity of the provinces. The theaters—that is to say, what one hears and sees in them—are quite as primitive and tedious as they are
elsewhere. A translated French play now and then proves a temptation, but as it is customary in Mexican theaters for the prompter to read everybody’s part, whether he needs assistance or not, in a voice as loud and often louder than those of the actors, the pleasure of illusion is out of the question. In fact, it is such a matter of course for the prompter to yell through a whole play at the top of his lungs (often reading the lines after the actors instead of ahead of them), that when, as happens once in a long while, his services are dispensed with, the fact is proudly advertised! I have several times gleaned from the advance notices of traveling companies that on such and such a night Señorita So-and-So would take the leading part in the laughable comedy entitled “‘Thingumbob,’ sin auxilio de apuntador!” (without the aid of the prompter.) Nothing in connection with the theater in Mexico has seemed to me more entertaining than this, unless, perhaps, it is that at the Teatro Limón in Jalapa, “The management respectfully requests gentlemen not to bring their firearms to the performances.” Whether or not this plaintive plea is on the principle of the old “Don’t shoot the organist; he is doing his best,” I have never been able to learn.
There are saloons in the City of Mexico, hundreds of them, but cafés of the kind that are such oases in the evenings of France, of Germany, of Italy, have not (with the exception of the delightful one at the base of Chapultepec, which, however, is several miles out of town) yet been invented. In the matter of restaurants (again excepting the distant Chapultepec) there is no choice whatever, if one happens to be in the mood to draw a distinction between eating and dining. People talk of the food at the various hotels, but when speaking of Sylvain’s restaurant they elegantly refer to the cuisine. Sylvain’s is a small, quiet, dignified, almost somber place where everything, except occasionally the service, is as wickedly good as it is anywhere in the world, and where the cost of painting the culinary lily is somewhat less than it is in establishments of similar excellence in New York (I know of none in the United States outside of New York) and Europe.
But taking the city as it is (always a sane and sensible line of action) rather than finding fault with it for not being what one assumed it was going to be, it has its moments—moments that, as far as my experience permits me to speak with a semblance of authority, are peculiar to itself. On Sunday mornings three beautiful allées of the Alameda are lined with little chairs and roofed with gayly decorated canvas, under which the world and his
wife sit, or very slowly promenade down one side and up the other in two densely crowded, music-loving streams. It is a variation of the plaza idea of the smaller places, the variation consisting in the aloofness of the classes from the masses. And by the masses in the capital is usually meant, although the distinction is a loose one, persons who still wear native costume. A cheap, ill-fitting suit of American cut is a passport to a slightly higher position in the social scale—which somewhat shoddy conception was responsible a year ago for the abolishment of the sombreros worn by cabmen. Until then, these towers of protection had imparted to cab-stands the character and distinction possessed by no other form of head covering. But now, no livery having been substituted, the drivers wear dingy felt hats, and carry battered umbrellas when obliged to sit in the sun.
The band is very large and very good—so large and good, indeed, that later in the day, at four or five o’clock, as one joins the ever-increasing throng of carriages, cabs, and automobiles on the Paseo, one is amazed to discover several others even larger and better, playing in the magnificent circular glorietas along the drive to Chapultepec. In the park at the Paseo’s farther end is still another, and whether it actually does play with more flexibility, feeling, and taste than the bands I have heard in other countries, or whether the romantic beauty of the situation—the dusky cypress grove, the steep, craggy rock, literally dripping with flowers, from which the castle smiles down at the crowd (it belongs to the smiling, not the frowning family of castles) the gleam of the lake through aged trees, the happy compromise between wildness and cultivation—weaves the spell, transmutes brass into gold, I do not know. The Paseo was begun during the French intervention, and although its trees and its statues of national celebrities are alike small for its splendid breadth (the trees, however, will grow), too much could not be said in praise of the conception itself, and the manner in which it has been carried out. It is one of the noblest of avenues and, with the Alameda at one end and the gardens of Chapultepec at the other, does much in the City of Mexico to make life worth living there.
The crowd of vehicles increases until there is a compact slow-moving mass of them creeping past the band stand, into the cypress grove, around the other side of the park and back again. Many of the carriages are victorias and landaus of the latest design, the horses drawing them are superb, the lady occupants are always elaborately dressed and sometimes notably handsome. So it is odd that most of this wealth and fashion and
beauty seems to shy at servants in livery. There are equipages with “two men on the box,” complete in every detail, but in the endless jam of vehicles their number is small. That there are not more of them seems especially remiss after one has seen the few. For in English livery a young and good-looking Mexican servant exemplifies more than any other human being the thing called “style.” As darkness comes on everyone returns to town to drive in San Francisco Street until half past eight or nine. This is a most extraordinary sight—the narrow thoroughfare in the heart of the city so congested with carriages as to be more or less impassable for two hours —the occupants under the electric lights more pallid than their powder—the sidewalks packed with spectators constantly urged by the police to “move on.” It all happens at the same hour every Sunday, and no one seems to tire.
When I said there were but few “sights” in Mexican cities I made, in the case of the capital, a mental reservation. Here there are formal, official, objective points sufficient to keep the intelligent tourist busy for a week; the cathedral, the Viga canal, the shrine of Guadalupe, the Monte de Piedad— the National Palace, and the Castle of Chapultepec, if one cares to measure the red tape necessary to passing within their historic and deeply interesting portals. Even if one doesn’t, it would, in my opinion, be a tragedy to leave without seeing, at sunset, the view of the volcanoes from the top of the rock on which the castle is built; especially as this can be done by following, without a card of admission, the steep, winding road past the pretty grottolike entrance to the President’s elevator, until it ends at the gateway of the famous military school on the summit. One also goes, of course, to the National Museum to inspect the small but immensely valuable collection of Aztec remains (large compared to any other Aztec remains, but small, if one pauses to recall the remains in general that have remained elsewhere) and to receive the impression that the pre-Spanish inhabitants of the country, interesting as they undoubtedly were, had by no means attained that facility in the various arts which Prescott and other historians claim for them. After examining their grotesque and terrifying gods, the incoherent calendar and sacrificial stones, the pottery, the implements, and the few bits of crude, gold jewelry, one strolls into the small room in which are left, perhaps, the most tangible evidences of Maximilian’s “empire,” reflecting that Prescott’s monumental effort is one of the most entrancing works of fiction one knows. To the unarcheological, Maximilian’s state coach, almost as overwhelmingly magnificent as the gilded sledge in which Lillian Russell
used to make her entrance in “The Grand Duchess,” his carriage for ordinary occasions, the saddle he was in when captured, and the colored fashion plates of his servants’ liveries, are sure to be the museum’s most interesting possessions. Not without a pardonable touch of malice, in the guise of a grave political lesson, is the fact that the severely simple, wellworn, eminently republican vehicle of Benito Juarez is displayed in the same room.
The four or five vast apartments of the Academy of San Carlos (the national picture gallery) suggests certain aspects of the Louvre, but their variously sized canvases suggest only the melancholy reflection that all over the world so many perfectly well-painted pictures are so perfectly uninteresting. One cannot but except, however, a dozen or more scattered little landscapes—absolutely faultless examples of the kind of picture (a very beautiful kind I have grown to think) that the grandparents of all good Bostonians felt it becoming their means and station to acquire fifty or sixty years ago in Rome. The Mexican Government, it no doubt will be surprising to hear, encourages painting and music by substantial scholarships. Talented students are sent abroad to study at government expense. One young man I happened to know was given his opportunity on the strength of an exquisite oil sketch of the patio of his parents’ house in the white glare of noon. He is in Paris now, painting pictures of naked women lying on their backs in vacant lots. Several of them, naturally, have been hung in the Salon.
But the guidebook will enumerate the sights, and the “Seeing Mexico” electric car will take one to them. Still there is one I do not believe the book mentions, and I am sure the car does not include. That is the city itself between five and six o’clock on a fair morning. It several times has been my good fortune (in disguise) to be obliged to get up at this hour for the purpose of saying good-by to people who were leaving on an early train, and in returning all the way on foot from the station to the Zócalo (as the stupendous square in front of the cathedral is called) I saw the place, I am happy to remember, in what was literally as well as figuratively a new light. Beyond a few laborers straggling to their work, and the men who were making the toilet of the Alameda with large, green bushes attached to the end of sticks, the city appeared to be blandly slumbering, and just as the face of some one we know will, while asleep, surprise us by a rare and unsuspected expression, the great, unfinished, unsympathetic capital smiled,
wisely and a trifle wearily, in its dreams. It is at this hour, before the mongrel population has begun to swarm, that one should walk through the Alameda, inhale the first freshness of the wet roses and lilies, the gardenias and pansies and heliotrope in the flower market, and, undisturbed among the trees in front of the majestic cathedral, listen to “the echoed sob of history.”
THE END
Typographical errors corrected by the etext transcriber:
Futhermore=> Furthermore {pg 73}
Oh que bonitas=> Oh qué bonitas {pg 179}
a desert=> a dessert {pg 185}
she as giving=> she was giving {pg 210}
exclaims her hushand=> exclaims her husband {pg 261}
innocent midemeanor=> innocent misdemeanor {pg 272} of preoccuption while=> of preoccupation while {pg 281}
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