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Home , Magnetic circuit, Magnetomotive force, Mechanical rectifier, Thermoelectric battery

A RESOURCE RESEARCH IN

For American Industrial Arts Education with Implications for Teacher Education

A DISSERTATION

Presented in Partial Fulfil latent of the Requirements for the Degree Doctor of Philosophy In the Graduate School of The Ohio Stete University

by

WILLIAM L J I H M DECK, D.S., M.A. Southwest Texas State Teachers College San Marcos, Texas

THE OHIO STATa UNIVERSITY

1955

Approved by:

Adviser Department of Educntion rtidf/ci;

The commercialisation of the phenomenon of electricity haa assumed amaBing proportions. The original presentation of lighting and telephone displays occurred only sixty yearn ago at the Columbian imposition in Chicago in 1893* Teas than 50 million dollars was spent for electrical equipment and service of all types during the year of 1900. This mushroomed to two billion dollars by 19^0 and

the current figure i» approximately twenty billion doilrre annually.

Such data oannot be ignored by those engaged in American public education, and especially by those in industrial arts education.

The question of whet to do about this problem has been accepted by

this dissertation. Its organization and development have been designed especially to answer most of the questions thnt should be resolved by the industrial arts profession.

The names of many students of this subject should be acknowl­ edged because the writer has been engrossed with t.h ' problem for some

twenty years and has had the very real privilege of working directly with those in industry. Chief among the above is f’rofeusor

Lawrence C. Scorest of the Industrial Arts electrical Laboratory in

the State Teachers College at LeKalb, Illinois. The writer is also keenly appreciative of the discerning guidance provided by his grad­ uate major adviser. Dr. William L. Warner and by the other members of

the consdttee. Hr. aarl V. Anderson and Lr. Andrew Hendrickson.

J u ly 1 3 . 1955 WIiiLIAM JuUTu-.Ji Oi*GX

11 Chapter

PREFACE

I. MATURE oy 'im Dili; :JtiA'i'lOli...... Mature of Electricity -Tolution Phases Terminology Assumptions Scope and Limitations Impact on Industry Iapact on the Individual Impact on Education Statement of the Problem Research Techniques Employed

II. l.I^CxuIJITY IB EARLY H M t K .... The Heavy Hand of Superstition ■Discovery and liaea of Development of evolution of Current Electricity

III. XLKCTHICIfl IN HOlAUiN TIMES The Generation of Electricity Industrial Usee of Electricity Domestic Uses of electricity Medical Uses of Electric! ty Electricity in national l>efence Electricity in the future

IV. Till'. RESOURCE STUDY OP ELECTRICITY Characteristics Magnetism The Electron Theory Current Cells Conductors Measurement Circuits Condensers Chmntar

-ranaformera Relays Svltohes Itynanoa Transmission Annotated Bibliography ......

V. iiAiUik A41L SCOP* OS’ Itfi)US*RlA*. ART! LDUG/TIOK . . . .

Derivation of a Statement of Position Resulting Objectives or i'unotiona Basic Programs or Scope of industrial Arts

VI. SLSCTHICm IN vH~ INDUSTRIAL Arf' S CUHnlCULUM . . . .

The kleoentary School The Secondary School Atypical Caaea Technical Barela Recreational Groupa Adult Intaraat8 Service Fields

v i i . u m j m c o t is U vD u s t r i a *. aius; i'-.ACHRh. iD-jCAxioa . . .

Situation in the State* and Colleges essentials of the ±hree degrees Basic laboratory aquipaent

VIII. SUM AnY A.Ni) COjCLUSIOBS ......

Findings of the hasource Study Recommendations 1. Inatructlonal Units 2. A Companion Dissertation 3. Administrative Officers k. Teacher ducation 5. Organised dfcperlmentation 6 . The Literature 7. Refresher end In-Service Ireining B. The Industry Itaelf

SkLi.CT.iD BIBj.IO(iKA?!lY......

AU'TQB I03RAPKT Chapter 1

HAi'URj-. Qi '£Rt. i^SAkiVU'IOk

1'his is a resource and program type of research. It focuses upon the electrical phase of the American t«chnolo(y with general reference to its impact upon nan and society, and with special refer­

ence to what should be done about it by industrial arts education.

l‘he industrial development of electricity Is of only very recent

origin, but in the short space of a half century has now become

almost universal. It is a necessity in present day society that

every individual know the intelligent application of it.

It is in agriculture aB well as industry, in the arts as well

as the sciences, in medicine and health as well as the home, and

in manufacture and transportation as well hr communication. In the

future it may take its place in relieving more human ills, i'oday,

it is possible for some industries to produce their product com­

pletely with electrical tools and fuitoroatic controls, i'he surround­

ings of the home cen be lighted automatically by a narrow beam of

light. Windows in the home can be closed automatically as a rain

storm ap roaches.

I'he school subject of industrial arte education has been

defined by Bonser (B, p. 5)« Wilber (86 , p. 2) and nany others, as

referring to thoee phases of general education which deal with

industry: its tools, materials, processes, products and personnel,

and with the problems that result from the interaction of these

1 basic elements. *he leaders of industrial arts have been concerned to interpret the technology not only me retards its production, but its corsumption too, hence this study.

HATdlii Oi KL'C'fKlCll'Y

Kleetricity was vaguely perceived over the centuries. It still cennot bo defined, but man has learned to use the charged particles of the atom, 'fheee particles, called electrons, were found to have tremendous effects. Ibis now phenomenon produced heat, motion, light, and chemical effects after it was brought under control.

fhe sooed of the electron is approximately 186 thousand miles por second. An is the flow or movement of elec­ trons. -ho opposition or resistance offered by the atoms of a conductor results in heat or light, ihe flow of an electrio current through r conductor produces mmiy invisible lines around it called magnetic lines of force. Vheae magnetic linns of force produce the magnetic effect when a conductor is colled about itself, i'his magnetic effect produces motion. Chemical change is created when an electric current Is passed through an or a liquid that conducts an electric current, 'l’his effect will store electrons, purify metals, or deposit one metal on another. is developed when f large number of electrons arc placed in motion, ihis is accomplished by turning a series of coils of wire in a strong mag­ netic field. 3

Kvouri’ioij

1‘his new phenomenon, electricity, hem become a slave to every man, woman, and child. It developod In the five stages noted bolow. f’he first of these la superstition.

Superstition. 1‘hi B phase began long before the observation of fhales and continued to the close of the Civil bar. ihe weight of superstitions about magnetism and electricity caused progress to be slow, Ahey were gradually' analyzed and discarded by experlmeota- tion.

Jtocuerl mental. This period began with the observation of fhales

6bO-5**6 B.C. He was the first to dany thnt the attractive force of amber was supernatural powor. He was the first to attempt to explain why it attracted straw and other material, ihe greatest vigor In experimentation wan exe:rted during th^ eighteenth and nineteenth centuries. By the letter uart of the nirrteenth century tho foun­ dation of electricity was established. Ir. this ;>«riod, electricity wab generated ny water power, bmall motors supplied jower for machines by transmitted electricity. Blectric railroads were es­ tablished. ihe incandescent light was developed and the first commercial electric power became practical.

Industrial, ihe "Jumbo* generators and the engineering feats of Sprague and others attracted industries in the letter part of the nineteenth century. By the early part of the twentieth century electricity was favored by industry more than any other type of u as a nource of power, ihib I'ovtRe:,; developed in ail major industries of the world, fhe new power created flexibility in industries. It aided the standardization of parts, and reduced the coot of production. Mieon and Westinghoune organirod oleotrionl engineers for production of electrical goods end machines.

Domestic. i'his phnee ntartod in the It tter part of the nine­ teenth century, but made its grenteet growth after the depression of 192 V. Batterlea at first supplied electrical power for street and hone lighting. ihia proved to be too expensive and was discontinued,

'ihe discovery of new materials and techniques made electricity avail­ able for domestic and industrial use.

msi-s

‘ihe superstition phase ia identified with many outstanding beliefs about arber, lodestone, and lightning. For example, many believed that the rttractivo power of amber vac pu iern*ttiral. 'ihe ifomr.n prieBte wore the Snmothrecier rings in religious worship.

Many belieAred the lodestones contained souls fallen from heaven, ihe belief that lightning was the wrath of the Uode prevailed for centuries, ihere was a long enduring belief that the diamond, and the odor of garlic and onions would destroy the power of the . It wan believed that powdered lodestone mixed with nettle

Juice would reduce fat. ‘i’hose and other superstitions will be enlarged upon in Chapter II. ^iperstitiona caused some challenge and a smell number made experiments to test them. 1‘hiu phase is identified by a tremendously largo number of experimenters that were important in developing the new phenomenon into a science. These experiments began with the obser­ vation of ihales, the Qreek philosopher of 6BO-5U6 B.C. Saint

Augustine discovered that amber would attract straw and paper but not iron, and that the lodestone attracted aetal or iron only. The

Chinese developed the magnetic compass Rnd it gradually made its way into -Europe. Peter Peregrinus refined the Chinese compass and created the lubbers point, Hobart Borman developed the dip needle. locperistent8 made by franklin, Galvania, Volta, , , and others will be discussed in Chapter II.

Industrial, ihe experiments made by Michael iaraday and Joseph

Henry and others were refined by experimenters Sprague, Bdison,

Meetinghouse, , and many more in an attempt to find practical applications of the new science. These experimenters developed practical means of generating current electricity by mechanical means, and ways of transmitting it to industries sites, for example, the

"Jumbo'’ generators developed by Edison, the Niagara falls power system, and the application of electric motors to machines by Sprague were attractive to industry. These developments and their influence on society will be expanded in Chapter 111.

Domestic. The developments that grew out of the experimental and industrial phases made rapid expansion and developments of the new technology after the depression in domestic uses. This was accom­ plished by developing wider applications of electricity by 6

Wsetinghouse, General Electric, and other industries. George

Westlnghouse and Nicola ‘ieala developed the alternating currant generator and the brushlass motor. This development made trans­ mission of current electricity jjoseible ovor creator distances and more economical than electricity. These develop­ ments made rural electrification possible *nd the great expansion

in the commercial and domestic use of electricity. These develop­

ments will he treated in Chapters 111 and IV.

ftltat Of tfafl sM a ^egan in the experimental

stage. -!Mllaon made a dieaovery known as tho *'41 son Effect” in the

latter part of the nineteenth century. Sir Alexander FLEMING

employed the ’effect" and created the two element tube known as the

AloAa. This device made possible the conversion of alternating

current to the direct type. Lee LE FOHIaST created the trlode by

adding the third element, the grid, to the Fleming . This

triode has many variations today and hundreds of ap licatione.

The field of electronics ia very closely allied to the subject

matter of this dissertation. The electron tube is a phase of elec­

tricity, but is omitted for the following reasons. First, there

is enough electronic content to develop a resource study equally as

large and rich as Chapter IV. Second, thore ar- phases of electronic

development equally as interesting and important as the phases of

electricity. Third, lta historic development is as ricv in material

as the historic development of electricity and magnetism. Fourth.

the applications of electronics to ind\>stry and domestic use are 7

Just as numerous aa electricity, ITif th. ita role In industry aa an automatic control of power and machines creates a phase of tech­ nology that needs interpretation.

TlfiHiMIilOLOGY

'i'he educational and scientific terma used in this dissertation are defined aa follows:

M u l t Education, i’ormal and informal Instruction and aids to study for mature persona, or all activities with an educational purpose carried on by mature persona on a part-time basis, or any voluntary purposeful effort toward the self development of adultB, conducted by public end private agencies, such ae adult schools, extension centers, settlements, churches, clube and Chautauqua associations, for informational, cultural, remedial, vocational, recreational, professional, and other purposes. It may use such forms of class or group gatherings as the colloquy, discussion, panel, forum, round table, rending circlo, institute, tutorial class, and short course. It directs its activities toward such special subjects aa cltiaenshlp, consumer problems, cooperatives, child welfare, farming, health, and industrial relations and to the field of art, literature, and science.

Amplifier. electric, a device to magnify electric Impulses usually including one or more electron tubes.

Atvulcal. not of the typical character, irregular, unlike the type. 8

fletectnr. radio. A device for rectifying high-frequency electric current, as to vibrate a telephone receiver diaphram, which of itself will not respond to such high frequency.

fliode. A tube with a cold or positive enode (plate> and a heated , serving aa a .

Edison effect. The flov of electrons from a heated cathode or filament to a cold or positive or plate.

Elan trial tv is defined as the flow of free el ctronethrough a metallic conductor.

Electronlea is defined ae the flow of free electrons through a vacuum or gas filled tube.

Electrolyte. / type of in which, when traversed by an electric current, there is a liberation of natter at the , either an evolution of gee or a deposit of a solid.

Electrical-electronic industry. A letter from the Chamber of

Commerce of the United States reports that:

Probably the best definition of this Industry is the United States Bureau of the Census electrical machinery industry* This Industry includes the manufacture of alec- trical industrial apparatus, electrical appliances, in­ sulated wire and cable, engine electrical equipment, electric lamps, communication equipment, and miscellaneous electrical products.

Elementary education. It is the period of formal education beginning in childhood, usually at the ago of five to seven years. and ending Approximately wit* adolescence, *»t the beginning of eecondnry education, or including grades one to eight, and some­ times? nursery school end kindergarten. It Is concerned primarily wit): general education including those shills, facts and attitudes

that are required by society.

Secondary education. ihe period of education which usually consists of grades sever to twelve during which pupils learn to use

independently the tools of learning that they have previously

mastered. It Is differentiated in varying degrees according to needs and Interests. It may be terminal or preparatory.

.ervlcas. Performance of useful labor portal ring to business

or industry, performance of official duties for a Rovoreit,n or

state as public service, and military or naval duty.

leq^nplrurv. Industrial ocionco or systematic Unovledgr of the

industrial arts.

Whose terms were developed fro’1- the fifth edition of Webster1 a

Coll^lRte dictionary and the ( 1 ^ 5 > first edition of darter Victor

Good, ^atlaapry at ^uuflUofl-

Ai'SUMPiiOkif*

'ihe teacher ami much that pertains to his success was examined

closely in view of certain stated assumptions of this dissertation,

ihe baslo assumptions are as follows! 10

1* -^rofenploni‘1 programs ere bated upon seated, assumed, or derived philosophies or policies.

It Ip believed that teacher education should reflect s cultural pattern whic; reflects the American way of life. Itn leaders must be thoroughly familiar with the complicated problems of the tech­ nological society, nnd of the tinny proposals for directing in­ dividual development in living in a complex society.

iVofeoeionel programs should exemplify the needs of a pro­ fession and lend out in its.development.

l‘he first professional need is to develop a curricula for cer­ tain clearly defined groups as for: normal groups at six levels, elementary, secondrr;, collegiate, adult, services, and ccnp and vacation; atypical tjouos such nr. crippled, partly seeing or blind, hard of hearing; or deaf, mentally retarded, social maladjusted, and the gifted; and professional ^rouue. rue) no baccalaureate and graduate levels.

A second obligation is ir. pro'/duin^, physical equipment for programs designed to attain orientation, technical, vocational and recreational.

’Ihe third need concerns the teachers end thoir qualifications, i'hls includes thoir intellectual and necha.iicnl pptituder, their social and personal development, and their skills an well as their attitudes and perspectives. 11

3. Teachers In tho field should he fully propAred to carry on their assignment as well as being ehle to project their programs

in the light of the technological and social trends.

The industrial arte teachers ere expected to develop a program

that ie functional and dynamic In nature, They 'mist be conscious

of an evolving technology end ready to adept their program to the origins listed In Chapter V.

SOOPis. AHD LIMITATIONS

It was believed Inadvisable to combine the two divisions of

electricity and electronics after reviewing the resource material.

It was the opinion of the advisory committee that a more plausible

resource etudy could be achieved with one division.

Selected tonic. In order to use the wealth of available

resource notorial, it was neceraary to limit the dissertation to a

resource and program research in electrioit, for industrial arts.

Pro*grana selected. College programs were eelected in light of

semester hours offered in electricity end course content. These

came from researches made regarding industrial arts teacher education.

IMPACT OU INDUSTRY

The effect of electricity on industry was a gradual prooese.

There were movements under way in the last part of the nineteenth

century, for example, one and seven tenths billion Incandescent

light bulbs were in use, end 3 ** electric railways were operating. 12 small electric motors were operating, elevator* and other machinery.

The movement made some progress In Industry shortly before

World *>r <1. The war brought a halt to the progress, but coon after its close, there was a period of rapid development and penetration.

Industrial enterprises tended "tore and mere to use electrical power In preference to any other form of energy. The movement gained In momentum once the conversion of manufacturing proceseee was made to the use of electrical power, and the Industrial and economic expansion of the principal countries became more and more dependent on the Increase in construction and equipment required for the production of electricity or the utilisation of it in industrial enterprises. Ihe electrification of hones has increased the impact on Industrial production, and will continue as the economic status of the home is maintained.

IMPACT Ob I1L. INDIVIDUAL

The influence of electricity ">ade its showing just before

World War 1. Human power at this time was almost equal to the tech~ nologlcal. Soon after the war technological power was approximately seven times greater than human. This increase in technological power provided more en9>loyment, more goods, higher income, and a higher standard of living. It has made a shorter working day, and as a result man has more leisure time. It has lifted nan from hard wearisome labor to a position of an observer, or a tender of machines. It has given man freedom In hla work, and provides for 13 creativenesc. It demands that man be alort, hays ability to analyse,

boo tha relationship of many moving parts, and think in electrical

terms and symbols.

It has made possible many automatic controls and devices to

stop and start machines. This replaces man with a machine. However,

man, in most cases, is still the tender. Many industries have been

affected by autosuttion. tfor example, ({lass, bottles, electric light bulbs, and electric generation plants are almost 100 percent auto­

matic. In the light bulb Industry 95 percent of all bulbs are made by automntic processes.

It has made a wealth of material* useful for man. *or example,

aluminum, asbestos, cerium, cobalt, helium, iridium, mica, molyb­

denum, plutonium, radium, tantalum, and thorium.

Man can he more exacting in his work for now tools such aa

electric motors, generators, photo-electric cell, x-ray, raruniflux,

infra red ray, electrostatic fiold, Mg) frequency heating have

been developed.

1 pjUCi OH jfiDUCWlUh

Old educational institutions such as the home, and the church,

weakened while new ones such as the printing press, industry, cinema,

telegraph, telephone, radio, and television appeared end prospered.

Then* have aided in forming public opinion and mass education, and

have brought great changes; for example, industrial civilisation lfc with an ever expanding technology. Hence, formal education ha* re­ ceived new significance in modern tine* and ha* become one of ooclety's most powerful institution*.

oi t ;l , hko b ;.w !

This dissertation is a resource end program research in elec­ tricity and the following objective* are developed:

To *how the early and pre*er»t historic development of elec­ tricity. This occur* In Chapter* II and III.

To show the value and it* application to agriculture, medicine,

■cience, health, as well as it* value and importance to power, man­ ufacture, transportation, communication, construction, and personnel.

These are aevelcpod in OiapterB 11 and 111.

To develop a resource study composed of the technical aspect* of electricity. This is developed in Chapter IT.

To ahow the relationship of electricity to th« nature of indus­ trial arts. This is shown in Chapter 7.

To develop example programs for the various group* of education.

This is developed in Chapter Tl.

To devolop and propose a program for industrial arts teacher education with emphasis on electricity. This is developed in

Chapter VII.

This dissertation include* an historic research on electricity in early times or from the age of superstition to the modern age, and is followed by a systematic and exhaustive resource or content study of contemporary electrical knowledge and practice reported under 15 seventeen headings enumerated below. dy way of application, the eub- jeot matter thus recorded in then adapted hi examples to the Indus­ trial arte curriculum from elementary to adults and aeveral levels, and concludes with • chapter of Implications for teacher education.

HKSKAhCH 2KC1I! J illft.3 jtfPLOXSD

hsunlly there is more than o io way of achieving a deaired objective, and frequently a number of different a > roaches to a given question will produce better rosults than one. With this thought in mind, for this dissertation, various technique* were employed in securing data for this study.

Bibliographies. iheso Include all available ra=terlals that had a bearing on this subject Including books, pamphlets, and periodicals in science and education which were reviewed.

historic, ibis material was found in small parts, and was screened from many' books, pamphlet*, and periodicals.

&xparlwant*i- Many hours were upent in thu industrial arts electrical laboratory experimenting with, mechanic' 1 and electrical devices, electrical circuits, and theory in an attempt to find new ways and methods of presenting the new technology to student*.

Personal Interviews, interviews vit> laymen, collage ntudents, industrial arts teachers and industrial arts departnart headH were made in regard to the electrical field.

Catalogs and Bulletins. Catalogs of verioua teacher colleges were obtained for program, nature of course*, and semester hours credit. State department of education bulletins were studied to 16 deterwi.no iho type of program recomnendod for secondary education and the emphasis on electricity.

jtivaluatlon. Objective and objective tents were given to laymen, college students sod industrial erts teachers to d termine their cohh> petency in the broad and specific ureas of electricity.

Deduction, The technique implied hero means arriving at conclu­ sions through an orderly procedure of summarising factual material.

Induction. The use of this technique involved the inferring of general conclusions from particular parts, ^“hie method of arriving at conclusions was used throughout.

uieationnalra. A chart questionnaire was used to colloct data pertaining to the number of semester hours offerod in electricity by industrial arts tencher oducation.

jjetterR. Letters were sent to the twonty state departments of education concerning their programs of electricity.

Dissertations. *he moet current doctoral dissertations regarding the dissertstlon were reviewed.

Personal

fhie study opened wit'1' a chapter which has nought to identify the elements of the problem and the fields of Inquiry which is concerned with resource material, programs, and teacher uroparetion.

Chapter II concerns the first phase of inquiry namely, electricity in early tlmen, which has intrinsic value to this dissertation. Chapter II

wjrasHicm m j.a h l y xmiis

i'his chapter ie considered to he basic to the dissertation, because it is a resource study. What now follows ie an historic analysis of four clearly discernible periods in the discovery and early development of electricity, i'hese Include, an examination of the heavy hand of superstition concerning the phenomenon of electri­ city that prevailed for many centuries, the ultimate discovery and uses of magnetism, the discovery and uses of static electricity, and the discovery and early uses of current electricity.

This chapter Involves historic and bibliographic research, fhe encyclopedias have been freely consulted in addition to such authori­ tative references as Benjamin (E), Burlingame (13). Draper (22),

Greenwood (31). Hodgins (36), and the industry itself. Major dis­ coveries have been underlined to facilitate their review by indus­ trial arts curriculum people and others concerned.

i’HE HEAVY HARD OS1 SUP.-JtS'f li’IOJi

Primitive man was ill prepared to understand the many evidences of electricity in nature and therefore rationalised about them as superstitions. l*he frightening nature of thunder and lightning were attributed to the angry Gods, and such odors as those emanating from onions or garlic were considered to be Btrong enough to destroy the magnetic qualities of the lodestone, which along with amber, were considered to possess supernatural powers.

17 18

SOCilA'i'JCS (**69-399 B.C.) in describing (4, p. 24) the divine character of the rings from Samothrace, a Creek island in the northeastern part of the Aegean Sea that had been visited by the

Apostle Paul on his way to Macedonia, had this to say:

.... but there is a divinity moving you, like that in the stone which Buripldas calls a magnet, but which is commonly known as a stone of Heracles (i.e. Hercules). For that atone not only attracts other rings, but im­ ports to them similar power of attracting other rings.

ibis superstition was so strong that Sanothracian rings were used by many church people of early times. They were worn by the worshippers of Cabiri (4, p. 25). and later by the doman priests.

Socrates also states that the Samothracien rings became the usual pledge of betrothal in PLINY's time, i'he Cabiric priests theorised

(^. P* 39) that the lodestone used in making the Sanothracian rings were suporanturally influenced, 'i'he Cabiri people were not the only ones to use the lodestone in their worship, ‘i'he priest of the

Cybele wore talismans, a figure cut or carved from materials under certain superstitious observations (4, p. 80) of heaven, of which the following description is typical:

.... the stones (betulae or Phoenician lodestones) were probably pieces of magnetic iron from meteorites, worn as divining talismans by the priests of Qylete, who supposed them to contain souls which had fallen from heaven.

i'he Chinese also attributed the lodestone to divinity. Some of their offerings, such as a piece of red cloth, incense or gold paper were assembled in the form of a Chinese ship and burnt over a lodestone. Chinese navigators not only considered the magnetic 1 ' needle pr a guide to direct their voyages through the ocean, out

believed the spirit which Influenced its rations to be the

guiding deity of the vessel.

SAli'i' A<>Gj:vfl;t£ tf&i-ky) A ) stated v;i, p. that when •

diamond waa laid near Iron, n raagnot would not lilt it, and would drop iron already lifted if a diamond waa held near it. 'ibis super­

stition lasted at least 1500 years. Alexander USCAAM, an itaglish

monk, reported the same superstition in 1195 A.I).

One of the aost Intereating superstitions of this period was

the belief that the attractive power of the magnet would also be

weakened or destroyed by the touch or odor of onions or garlic.

Benjamin (b, p. Ib2 ) reports thrt:

.... among the superstitions relating to it, none for example, was store common than the belief that its attrac­ tive power could be destroyed or weakened by the touch or even tho odor, of onions or garlic ....

1’his was a common belief and it also lasted at least 15JO years.

Bautista POttlA (b, p. IkJ) who experimented with the magnet in

the sixteenth century, ridiculed the delusion prevailing even in his

time which caused mariners, when in charge of the lodestone, to avoid

eating onions or garlic because either would deprive the stone of its

virtue. and by weakening it, would divert thorn from their true course.

Another superstition is reported by in 1569 in his book,

Certains Secrete bonders of Nature, (b, p. 157J in which he describes

a "creagus" or "flesh magnet," of stone which cannot be removed with­

out tearing the flesh, 'fhis superstition lasted for at least three 20 centuries, because the wonder bool.B of tho time referred to a kind of "adamant whioh draweth unto it fleshe," and that 'it hath power to knit and tie together two offending mouths of oontrary persons, and drawe the heert of a man out of his body without offending anjr part of him."

Robert HDKMAN, an Englishman, did hia experimenting in the middle of the sixteenth contury, and disproved several superstitious ideas and beliefs. Among these were auoh items as (a, p. 219i- e magnet oarrled on the person will cure cramps and gout, will draw poison from a wound, deaden pain and facilitate childbirth, draw gold from a well, speak with tho voice of an Infant when sprinkled with wator, make a man mad when mixed with nettle Juice and serpent fat, drivo him from his kindred habitation and country, render a person gracious and take away fears and Jealousies, oauso one to be persuasive in his conversation, assist burglars bocauso if burned in a house it would cause the innrtse to believe the house to be falling down and then to flee, leaving the house for the thieves to seise anything they desired.

Xn the days of Pharaoh when God was showing him that He was a stronger power than Pharaoh, He commanded Moses (flotodus 9 :23) to stretch forth his hand toward heaven, and the lord sent thunder and hail, and tho fire ran along upon tho ground. Xn writing tho low of Sinai, lightning and thunder accompanied the presence of God.

Exodus, 19:16 "and it cams to pass on the third day in the morning, that there were thunder and lightning, and a thick cloud upon the 21 mount, and the voice of the trumpet exceeding loud, *o that all the people In the camp trembled."

'i'he church in the Middle Age* in Mirope was the object of many

(3 2 , p. 5H5) superstitious ideaB, nnci it was au >poeed that it had an influence in warding off disease, evil spirits, hurricanes, thun­ der and lightning, and malign influences of all kinds. It was the custom in many parts of Europe when a thunder storm approached to rinb the bells in the steeples. Jacob Abbott states that when a storm passed away without doing any special damage, tho peasants attributed their immunity altogether to the ringing, but if it proved severe, they attributed the results to not having runfo the bells loud enough!

Other techniques were used in another part of Europe to appease

the gods of thunder and lightning. Studente were instructed in the art of determining the will of tho godp by checking the location of

the lightning, if lightning flashed in one sone, it was a favorable omen, but if it flashed in another, it wnn fatal, The accomplished augurs stood on lofty towers watching for r gleam of lightning or a peal of thunder, and they knew at once concerning what to expect.

I'he first known attempt to break with superstition (h, p. 3 3 ) was taken by THALKS (6**0-5h6 B.C.) when he refused to account for

the magnetic properties of amber aa the priests and worshippers at

Samothrsce had done for centuries, l'hales assumed a soul or a vir­

tue to be Inherent and existing in the magnet. Thales' doctrine of 22

the inherent eoul therein was in direct contract with the prevail­

ing theories fostered by the priest of Cabiric mysteries, namely

that the stone was supernaturally influenced.

lil'JHK'i.'iUS (96-55 B.C.) a Homan poet, who wrote "On the Nature

of Things," told of the Samothraclsn rings existing in 95 to 52 B.C.,

and described the binding power of the stone as having a contin­ uous current. Lucretius said (4, p. 48) that there streamed fro*

the stone "very many seed* or a current, if you will, which "dispels

the air" which lies between the iron and the stone. This theory

helped him to explain attraction. He was? also the first to explain

the repelling action of the lodestone, and he described the action

of iron filings in a brass basin when the stone was placed beneath.

This was the first time the had been explained by

noting its effect on iron filings, and not merely by the attraction

and repulsion of one magnet to another.

PLl/fAiiCH (46-120 A.L.) described (4, p. 5 0 ) the attraction and

repulsion of the stone 150 years after Lucretius. It took many

centuries for man to reach the conclusion that a magnet would at­

tract on one end and repel on the other. It was long believed that

the stono which repelled was totally different from the one that

attracted.

SAINT AUGUST I Nii (354-430 A.L.) made an important observation

when he stated that he could not answer why the lodestone refused

to move straw and yet snatched iron. This was the first observation 23 of the difference between magnetic attraction and charged material*, euoh an amber.

?kit some of these superstitions persiotod, for example in the eighteenth century ('>, p. 50-’) concerning the replication of electricity to the curing of h ’imnn 111*. ihis va* the notion that fire existed in the human body capable of being kindled or expelled by electrification. This belief was found in America in 16P3» in Italy in 1?33» end In Germary in 1?M;. B1AHCKI.M gives an ac­ count (h, p. 503) of the spontaneous combustion of Countess Cornelia flandi, who retired one night in good health, only to bo found next morning es a heap of ashes.

DISCOVMY AND USJiS 01' liAGlWl'ISM

Another forward step In the development of electricity was expressed in a poem written by WIL..1AM, the Clerk, between 1159 and

117'>. In the last three verses of the laBt sterra (*», p. 151) he said:

bote the way the needle tends 'through its place no aye can see 'ihere the polar star will be

‘I'his is the first reference to the north and south directional pointing of the compass needle and *as a long stride ahead in that it explains a phenomenon by natural and not supernatural causaa.

A new concept on magnetism was reached by hoger BACOX (121b-

1294 A . D . ) in the thirteenth oentury. He did a great deal of experi­ menting with the lodestone end and concluded (**, p. 162) that the magnet was influenced by the four parte of the heavens. I

24

‘i’his was an amplification of the iden held by William, the Clark, who used only one part of tho heavens, the Pole star. If Bacon did not actually discover the law of magnetic rction (i.e. like poles mutually repel, unlike polos at tractJ, ho come very close to doing so*

Bacon had a friend by the name of Mediator Petrus MAHA&Ui-

CUHIA or Master Peter -OS MABICOUJtt’. Bacon colled him (4, p. 165) a ’’master of experiment." He was given the surname of "PfiiUSGiilHUS" or Pilgrim by the historians for his active part in tho Crusades.

Peregrinue did his work in the middle of the thirteenth century, and drew many conclusions that contributed richly to the development of electricity. He differentiated the poles of the megnejt. rmttlttfl that unlike poles attract, showed how to dotect magnetic poles and demonstrated that two nolea persist in every uart or fragment of. a divided magnet. He proved that not only is an iron needle attracted by lodestone, but that it will assume an inclined or angular position when brought into proximity with it. He explained the stress exist­ ing in the medium surrounding the magnet. which w^s set in the direction of the lines of force emanating from the stone. He ex­ hibited the nature of tho magnetic field, and found the position of the poles on a globular magnet. He recognised the magnetic meridians upon its surface and was the first to perceive the correct way of measuring magnetic strength. He also discovered fchf gutability tf, magnetic aolaa. and that the poles of a weaker magnet could be re­ versed or obliterated by the inductive action of a stronger magnet. 25

Ho invented the first mariner's comuass. It was the first to have a "lubber*o* or fiducial. BClja.1 «nd s grftdur-led ftfffllg. H *»« the first cnpable of being used to neeoure azimuth or bearing and the first to have a pivoted needle, This Ik fundamental to all electrical measuring instr\unento in which such an indicator is employed. He wan the first to surest the conversing nf ma^nat^o energy to mechanical energy in on organised machine to do useful work, and he was the first to surest a magnetic or .

Very little wes added during the following century (4, p. 190) to the discoveries of Peregrinue, nor was his compass improved.

The next important discovery was that of magnetic variation by

COLUMBUS in 1492. •Variation'1 however was known by the Chinese

(4, p. 197) as early as the eleventh century. There ir> no record, however, of any auropean recognising the variation of the needle as a cosmic phenomenon before Columbus did bo on hie memorial voyage.

This discovery did a gre^t deal to promote shipping and navigation.

Many countries started exploring and carryinb on con/nerce th?t had not done so before thiB discovery. The world was circumnavigated in 1520 to 1522.

Another step in the understanding of electricity was the dis­ covery of the dip or downward inclination of the magnetic needle.

Peregrinue discovered (4, p. 211) the inclination of the needle to a globular magnet, but not to the earth. H.AiffMAi'M, in 1544, dis­ covered the Inclination of the needle to the earth, but did not understand it. fiobert MhMAti, an Instrument maker of Bristol, 26

England, gave the first correct interpretation 01' the dip oi' the comunsB needle in 1576. Peregrinue discovered why the needle turned in line with magnetic force, Columbus explained the varia­ tion of the needle, and Norman dincoverud and measured its inclina­ tion. i’hia resulted in two components, horizontal and vertical, or the magnetic field of force about the earth or a magnet.

Pietro SAKPI made another discovery (4, p. 2243 in the latter part of the sixteenth century. Hie genius was expressed in many fields: language, mathematics, history, astronongr, geometry, magnet­ ism, botany, hydraulics, acoustics, and others. Hie refinement of magnetism was the destruction of the qualities of the magnet by heating it. ihis van a big blow to (4, p. 227) those who belioved that the power of the stone was ioijlanted by providence. Another important discovery by (Hulio CSlSAftB in 1586 revealed that iron could be magnetized without a magnet, lie was the first to work with a magnetic field of force.

John Baptiste POlii'A, 15^5-1615* was a student of Sarpi from whom ho learned much. Each was skilled in optics, and knew that the radiation of light varied ^4, p. 2137) with the square of the distance between the surface on which it fell, and the source of radiation, i'hey detected this similarity of the field around the magnet. Porta visualised a system to apply the mariner's compass to a new use in 1558 and it was tho forerunner of the telegraph

(4, p. 2393: 27

I’o a friend( that is a far distance from us, fast shut up in prison, we nay relate our minds, which 1 do not doubt nay be done by two Mariner's compasses having the alphabet writ about then.

A similar statement (52, p. 9) concerns 2©rta who referred tos

sympathetic needles magnetised by the sane lodeatone, mounted on separate dials with letters around their margins. When one needle turns, the other moves to the same letter.

William QILBKHf, 1544-1603, an Jfinglish physician, was first

(4, p. 383) to investigate natural phenomena systematically

(52, p. 14; and early recognised electricity to be different from

— gnstlf. end as a new natural condition of force which he named.

He suggested the correlation of gravity and magnetism with other natural forces, and a ralgtlonshl > between cavity, magnetism, and electricity. He recognised the earth to be a grert magnet, capable of magnetising iron and iron ore by induction. He determined the Bfllarlfr Qi the garth and the, true reason for the action of the

CMPMft. He discovered flftimttUQ IgmnlrUi* conduction, , the compound magnet, the mutual attraction; of induction of lodestone and iron, and the pole piece or armature. lie also discovered the nature of electrical charges and the degree of their permanence.

He was Also the first to Invent the electrical, as distinguished from the magnetic, suspension, and the ordinary method of magnetisa­ tion.

'fhe first political use of magnetism was (4, p. 205) in March of 1493 when Columbus discovered that the line of magnetic varia­ tion was permanently fixed. MASfHi V (4, p. 205), had already given 28

Portugal all tho territory which her mariners might discover be- tvoon Cope Bojador and tho Bast Indies. In :

ALKKAHDaH aligned all lands to Spain that were south and west of a lino drawn from the Arctie to tho Antarctic Polo, one hundred leagues voat of the Aaorea. All the world to be discovered was partitioned between these two countries with tho line of no varies tlon to separate thulr respective possessions.

OALILaXl QAL1LKX (156*4-16*42 A.I).) made the first announcement

(d, p. of the true effect of the armature or bar acroes the ends of p . He snid that n magnet would lift its weight, but later stated th^t it would 1 U & jfUUr. U » t H i Wgjgfal*

DiSCA_tfjL'&S (I596-I65OJ endorsed Gilbert's cosmic theories. He saw (h, p. 359) that there was a force, not merely radiating from magnet poles as Cabaeus supposed, but traversing tha atone from pole to polo in one direction and then traversing the stone exter­ nally from pole to pole in the opposite direction, i^esoartes discovered the tndltafBMl PJf ll M a gjf..WfigttflUO iQffifl. vhloh he referred to as spirals or ribbons.

ia£VHLOPM&/i OF £»A21C Blj2CWUCIxr

Otto VOV OUiatlCiGB, who was noted for his experiments and con­ tribution in pneumatics, made the first static machine. It was composed of a ball of sulphur mounted on an axle th*t was turned by a crank and excited by the frlation of the hands. He used the globe to show how it possessed certain characteristics (b, p. 396) 29 such aa, impulsive virtue, conservative virtue or gravity, and directive virtue or magnetic force. Artificial litoht was detected and extended by Jean PICAiiL, a member ox' the Koyal Acadengr of

Science who observed this phenomenon in a mercury barometer in

1675 » Many experiments were made to discover the nature of thiB light.

JPrancie H AUK SB KB, an Knglishman, found (4, p. 465) that rubbed glass glowed because glass is an electric medium and is activated by rubbing. He grew tired of nibbing glass tubes, however, so placed a glass cylinder in his lathe in order to revolve it* 'i'hie wsb developed in 1709 (52, p. 11} end was called an electrical machine. It wae composed ox a hollow glass sphere or globe which was rotated by means of a belt and crank arrangement. Hauksbee observed that if he rotated it at the proper speed and placed hie hand on the surface of the revolving glasn globe, it would create a light bright enough for reading. One experiment involved two globes located within an inch oi each other on separate lathes so they could be rotated independently. ho ^4, p. 46?) removed the air from one and applied his hands to the other globe. Light ap­ peared in both globes and this was the first indication of mutual induction. Kauksbee's achievements attracted wide attention.

Hewton also experimented with glass globes between 1704 and 1717*

Wall was the first (4, p. 469) to see the similarity of the crackling and light in the globes to the thunder and lightning of nature, and won immortality from this observation. 30

John W'jOD, an Bnglishraan (52, p. 11) discovered. in 1726 that static electricity could be conveyed by a piece of wood. Up to this time, no one except Von Ouericka p. k72) had attempted to cause electric 'virture'' or current to pa«B from one bod; to another. Stephen GRAY did thin by placing corks in the end oi a glass tube, and then wooden rods. He used iron, brick, tile, chalk, and vegetable!? to transmit electric "virture." He then ex­ perimented to see how far it would travel by using hemp thread and fishing rods, but his rooms were not large enough. He visited a friend bj the name of John OODJTHBY in 1729 and (b, p, b73) experimented with longer lengths oi rodo which soon gave way to thread. He was able to electrify objects at the end of thread thirt.-four feet long. Gray visited another friend by the name of

Granville WHJdiUER in 173G who became interested in these experiments and they sent electricity (b, p. ^77 ; over ^66 feet of wire.

Gray identified two types of materials, conductors and non­ conductors, mid these led to the discovery of electrical insulation.

Ihey supplanted (52, p. 11) Gilbert's clasaification of electrics and non-electrics. Another outstanding contribution vaa mode in

1732 when he demonstrated (b, p. ^77) that the or

■’virture" of a glass rod could be communicated to another rod or line at a distance of one foot, fhis provod for the first time that a conductor or wire could Induce a charge in another conductor with some distance between them. 'I'his is the second example of 31 JlUtUtU

Charles i'rancois de Clsternay DUi'AY, a member of the breach

Acndeiny of Science, tried all of Gray's end Wheeler's experiments,

and added many new materials which could not be electrified. He

electrified metals which had not been before because oi' improper

insulation. His most important discovery (d, p. d84) was that

glass and crystal operated in exactly opposite ways to gum-copal

and amber, i'his led to the discovery of (52 , p* 11) two types of

electricities* He called the electricity yielded by glass as

vitreous, and that derived from gum as resinous. He discovered

and announced the fundamental law of elctricity that, "like charges rsaeJL anrt mUllrc chtyrgBs am asl-" *’or example,yXinvu.. rwaidi

vitreous and rflJlBflHfl. mlQQUJS. or m i B W 8 ftUrggjg

vitreous and vice versa. Ho found that any material could be elec­

trified by insulating it on glass stands. He also found that

moisture assisted the pasaago of current in thread, that items most

easily electrified by friction were the worst conductors, and that

those hardest to electrify by friction were the best oonductorR.

He coined the terms ''conductor" and "non-conductor."

Grey *a* stimulated by Dufay, i’he things he had said about

the burning sparks of electricity aroused Gray's curiosity. He ex­

perimented with fire shovels, pokers, tongs, pewter plates, iron

balls, and dishes of water. i'hese were hung on silk threads, end

(d, p, U8 6 ) the crackling sparks which resulted were inflicted on

a white rooster a-d then on a small boy. He was astonished beyond 32 measure with an iron rod which exhibited, the true brush discharge.

He stated that, "the flames are real and they burn and crackle and explode, iho effects at present are small, but there nay be found b way in time to colloct greater quantities of it, and consequently to increase the force of this Electric *lre.* i'his seems to be the same thunder and lightning in datura, i'his is the second comparison of the electric spark and its explosion to thunder and lightning.

DttSAGUILIKKS appeared on the scene after Dufay's death and became a prominent member of the Royal Society. He wan the first

(if, p. 4fi9) to electrify or charge running water. Gilbert caused rubbed araber to attract a water drop, i'ho ilorentine Academy had drawn oil up in little viscous strings by the same manner, and Gray had electrified a soap bubble. Desaguiliers found thnt water running through a copper fountain could be electrified so it would attract a string, or by holding r charged glnsn rod near a stream of running water, that it would bond toward the rod. He appears to have been the first to conceive of atmospheric electricity, and pointed out thst a cloud or mass of vapor may be an electrified body. He also recognized thnt air could be rendered electrical, and supposed it to be made up of electrical particles which were constantly repelling one another.

'i'he similarity of crackling electric sparks to thunder and lightning was recognized by Hnuksbee, Vail, and Gray, and the con­ ception held by Desagulllers of electrically-charged clouds and 33

Atmosphere, were forerunners to Benjamin franklin's famous dis­ covery.

the early development of static electricity occurred in

Greece, Italy, frar.ee, arid England. The year of 1?42 marks (4, p. 491) the beginning of an Interest in static electricity and machinery in Oermany. The German scientists were familiar, however, with the progress made abroad during the past fifty years, but the experiments that produced electric sparks or fire finally aroused

the attention of the people, The philosophers became interested finally because fire was believed to be a material substance, and

it was the idea of a human being becoming a torch that aroused

the German mind.

Two leaders are given credit (4, p. 493) for stimulating an

interest in electricity in Germany. These were Christian August

HAUSKN and George Matthias BGSB. They developed a larger and more powerful electrical machine than the ones created by Von Guericke or Hauksbee. Bose did many interesting things with static elec­

tricity which won him the name (4, p. 49$) of "modern wlsard." He used several siseo of globes at the same time and produced glow

discharges, and stated that they glowed, turned, wandered, and

flashed, and that no name was bo applicable to them as the Northern

Lights. 'I'his was the first suggestion of the electrical origin of

IL i. murpraJaoreaUi- «* Christian frederlck LUDOLl'I, a member of the Berlin Academy,

ignited warm "sulphuric ether" with an electric spark in 1?44. He 34 ignited alcohol end turpentine, and Bote claimed to taeve Ignited such liquids an alcohol, turpentine, butter, resinB, sealing-wax, and sulphur. He auceeBfifuliy exploded gunpowder after arranging it eo it vou-d not be scattered by the discharge from the rod.

He aieo made the firet atep (d, p. 4/7) toward the invention of an electric fuae, and there was no doubt that the electric spark and fire were the same.

Johann Gottlob KHUG&H. explained the medical uses of electricity in 1743. Here begins the modern effort p. 5®1) to apply elec­ tricity to the curing of human ills.

Christian Gottlieb BtAIfilWb'i’klll in l?4d (d, p. 502) made the first experiment to determine the effects of electricity on the human body. He observed a marked increase in pulse-rate, and an accelerated circulation predicted by Kruger, and the irritating contractual effect upon the muscles. Vhis stimulated the desire to increase the sise and charge of these ’^chines.

Andrew GU»DQh, a Scottish monk and teacher at Erfurt, Germany, substituted a glass cylinder for the globe. Johann Heinrich klHKLlui, a professor at Loipslc, replaced (d, p. 506) the dry palm of tho hand with a leather cushion rubber adjusted to the glass by springs, and rotated the cylinder with a cord and foot treadle.

He was able by this means to revolve the cylinder 6H0 revolutions per minute. I'his created greater shocks and brighter sparks than any previous electrical machine and couxd be produced in any 35 weAther, no mutter how damp.

The practical use of electricity was approaching rapidly.

The first to reaj>ond was Andrew Gordon, who invented (3 6 , p. 81) the firet electrical machine. Von Guericke generated it, Stephen

Oray and Vheeler transmitted it, and (lordon used it to ring a bell

(**, P» 5G7) composed of two gongs and n metal ball auapended by a silk line in proximity to one another, then the ball was electri­ fied, it moved to one of the gongs, struck it. then was repelled to atrlke the other, which again repelled it. He also invented the first (static) electric motor, it was a metal stnr pivoted in the center, and having the points turned slightly to one side in tho same direction, fhe reaction of the discharge of the elec­ tric machine caused the star to rotate. He also used electric charges to kill chaffinches, a slsable bird, to show tho power of the sparks from his machine. The similarity of electricpl flashes to lightning have been mentioned end when Gordon killed birds by then, another resemblance to lightning was recognised.

Dean VON XLhl&T* (d, p. 512) reported his findings on October 11,

17*5, on an experiment to electrify a nail in a medicine vial shaped like a klorentino flask. He stated that strong action took place if mercury or alcohol were in the vial. He did many things with this apparatus, and found it would hold a charge (d, p. 51L) for twenty- four hours. This was the beginning of the Leyden jar. 36

Wilhelm Jacobs OEAVXLAi*UL‘ and Petor VA1* MUZUGU^dihOKGK wars eminent Dutch physicists, They introduced the experimental phil­ osophy end the hewtonian doctrines into their country (h, p. $16), and established a systematic study of thene subjects at the Uni­ versity of Leyden.

Van Musechenbroeck was a student of Oraveeande1 a, and decided to imprison or store electrical fluid in a Jar by charging some water in it with an electrical machine. He stored a tremendous amount of static electricity in the Jar. and when he touched it, he received such a severe shock (3 6 , p. P-5) that it knocked him un­ conscious. In 17^6 v>, p. $19) "^usschenbroeck wrote his friend hene iieaumur the following account:

I wish to inform you of a new, but terrible exper­ iment which I advise you on no account to attemot. I am engaged in e research to determine the strength of electricity. With this object I had suspended a gun barrel by two blue silk threads which received elec­ tricity by communication from a glass globe whicv- was turned rapidly on its axis by one operator, while another pressed his hands against it. from the opposite ond of the gun barrel hung a brass wire, the end of which entered a glasB Jar, partly fxxli of water. ihin Jar 1 held in my right hand, while with the left I attempted to draw sparks from the gun barrel. Suddenly 1 received in my right hand a shock of such violence that my whole body was shaken as by a lightning stroke. Vhe vessel, although of glass, was not broken, nor was the hand displaced by the commotion, but the err and body were effected in a manner more terrible than I can express. In a word, 1 believed that I was done for.

‘i’his apparatus was called the "Leyden labial" and later the

"Leyden Jar." After its development, the philosophers saw in it 37 only a device for arentin^ greater shocks than before with the electrical machine. Abbot MlLLf?!! and Daniel GHAj-.axH killed birds with itB discharge. It wan considered n great invention at the

time it was invented, because it could store electric charge and produce discharges of unprecedented strength. It wan the fore­ runner of the condeneor which occupies a very important place in electricity today.

Abbet bollet entertained the king by discharging the Leyden

Phiel through 1H0 of his guards, (L, P. ljZk) "who wero ail oo

sensible of it, the surprise caused them ell to spring up at once."

however, this wai? soon outdone by the Carthusian monks in Paris who formed a line 900 feet lon^ by means of iron wire of propor­

tionable lengths extended between every two men. When the extrem­

ities of this long "line* or viro cnrx in contact with the elec­

trified phial, the whole company gave a sudden Jump and all felt

the shock equally, i’his is tlx* first indicatio1 of an electric

circuit.

hollet did nany interesting experiments wit): the electric

machine and the Leyden jar which added to the knowledge of elec­

tricity. One experiment was to discover the effects of electricity

on vegetables and animals. He (h, p. 5^7) planted mustard seed

in two receptacles, and maintained on*; in an electrified state for

eight days. He says, "the electrified seed had all sprouted by

the end of that time and had stalks fifteen or sixteen lines in 38 height, while onl. two or three of tho non-olectrified plants had appeared above tho ground, ar.d even these had stems not more than three or four linos high.'1 He then experimented, with animals, small birds and pigeons and concluded (H, '• that in all esses there was a loss of weight.

Winkler of eipsic discovered that when electricity had

several paths to choose ('■, p. $'jQ) it appeared to traverse the one which was composed of the best conductor. Another individual inter- ested in this was louis Ouillaume L& MOan1 dt, a trench exporioontor.

He created the first circuit by discharging a hoyden jar through two persons, a chain, and a lake of water. A circuit wae made thus early in 17^6 including both water and a metallic conductor, over which passed the discharge ox the jar, so that the two observers were shocked simultaneously.

i'he ability to store electric charges in the Leyden phial and the increased pow^r from the electrical machines created other queetioue whicr caused more experimentation and study, i'wo impor­ tant questions were: what distance will the electric charges travel, and how *, will it take them to get there, xhe htoyal Society assigned William WATSOii to answer these questions. Watson started his experiments in 17^7 to determine the distance that s charge would travel. His first experiment 0 6 , p. 89 ) included 800 feet of water and 2000 feet of land, the second included 8000 feet of water and 2800 feet of land, and a distar.ee of 12,276 feet was 39 transmitted in 17^ , but hie instrument-.; wore not accurate enough to determine the speed of the charge over the transmission lines.

Li*; worked with long conductors, end sought to measure the velocity- with which the electric charge ran over them. He also met with failure. He estimated the speed p. 53?) to be thirty times that of the velocity of sound in air. He also believed that the electric charge was communicated to bodies in proportion to their surface and not to their masses.

Watson (d, o. 53 6 J expressed his idee of the law of resistance in 17**7 as, "the resistance of a conductor to the passage of elec­ tricity, is proportional to its length and depends upon the material of. which it is comoeed. " vhie wes the beginning of 's basic law.

As the century drew to a close (h, p. the growing com­ merce of England created a demand for morn V-nov ledge concerning the compass. I'his created moro interest in the st-«dj. of variation, *nd in 1300, William 3UkB0 .