CHAPTER II.

DISCOVERY OF THE LIGHTNING CONDUCTOR.

With that liberality which distinguishes all truly great minds,

Benjamin Franklin did not keep his great discoveries to himself,

but communicated them to others in the most open-handed manner.

Ever since he had commenced his electrical experiments, he had sent

the detailed results of them to his London correspondent, Mr. Peter

Collinson, for communication to the Royal Society, and he was not

even prevented from continuing the labour of writing long letters by

the knowledge of the fact that scant notice was taken of them by the

Royal Society. The members of this august learned body, with a few

honourable exceptions, seemed unable to hide their contempt for what

they considered the dabblings in science of a mere tradesman, living

in an obscure little town, in a distant colony. Somebody had mentioned

in public that this person, of the name of Franklin, was a dealer in

rags and goose-feathers, dwelling among money-worshipping Quakers in

the City of Brotherly Love: which naturally was productive of great

merriment, but detrimental to scientific respect. Thus, although by the

influence of Mr. Collinson and some of his friends, the letters from

Philadelphia were read before the Royal Society, they met with scarcely

any attention, and the members broadly expressed their disdain of them

by refusing to allow their insertion in their ‘Transactions.’ Three

whole years elapsed in this way, when at length, in the autumn of 1750,

Benjamin Franklin reported to Mr. Collinson his researches on the

identity of electricity and lightning, together with his ideas that all

damage done by the electric fire descending from the clouds upon the

earth might be put a stop to by fixing iron rods, with sharp points, to

the summit of buildings, which would thus be protected. He added that

he himself intended shortly to verify his conclusions by experiments,

but that, in the meanwhile, it would be well if others did the same.

Never before, perhaps, was a grand idea thrown out to all the world

with more munificence of spirit, and with more entire abnegation of the

very thought of self.

Franklin’s letter made a great impression upon Mr. Collinson. Anxious

to make it public, while persuaded that the Royal Society would give no

better reception to it than to the author’s previous communications, he

hastened to Mr. Edward Cave, proprietor and editor of the ‘Gentleman’s

Magazine,’ and asked him to print it in his publication, the most

widely read at the time. A man of quick sense, Mr. Cave, too, saw at

once the vast importance of Franklin’s paper, describing his discovery,

and readily offered to print it, but recommended that it should be done

in pamphlet form, as likely to make the facts even more extensively

known than could be the case in his own Magazine. This having been

agreed to, there appeared, early in May 1751, a pamphlet with the

name of Benjamin Franklin on the front page, and a preface by Dr.

Fothergill, entitled, ‘New Experiments and Observations in Electricity,

made at Philadelphia, in America.’ It was the most important

contribution to science published since the appearance, five-and-thirty

years before, of Newton’s ‘Principia.’

Like Newton’s book, that of Franklin was not immediately successful--at

least not in England. Not appearing under the patronage of the Royal

Society, the supposed fountain-head of all legitimate science, it

was looked coldly upon by the public and the critics, and it was

only after having been greeted with immense applause in France, that

at last something like justice was done to it in England. The great

success of Franklin’s little treatise in France was due, in the first

instance, to rather accidental circumstances, but was none the less

genuine. By a happy chance a copy of the pamphlet printed by Mr. Cave

fell into the hands of the Count de Buffon, the greatest naturalist of

the age, and whose pre-eminent position was established not only in

France, but throughout the whole of Europe. Himself familiar with the

English language, he yet thought that it was necessary to have the book

immediately translated into French, and he employed for the purpose

Professor Dubourg, a literary man of note, well versed in electrical

science. Under such favourable auspices, Franklin’s pamphlet, carefully

translated, was issued at Paris in the summer of 1751, three or four

months after its appearance in London. Its success in France was as

immediate as it was great, and the wave of it spread at once over

Europe, marked by German, Italian, and Latin translations of the ‘New

Experiments.’ For a considerable time nothing was talked of among the

upper classes of France but the discoveries in science of the unknown

Philadelphia printer, and the king, Louis XV., following the fashion of

the day, ordered a course of the electrical experiments, described by

Franklin, to be performed before him at St. Germain, in the presence of

the whole court.

A rather ludicrous incident, and which gave rise to a great deal of

scientific tournamenting, added to the celebrity of Franklin’s little

book on the continent of Europe. The greatest of French electricians,

Abbé Nollet, a man of acknowledged merit, but inordinately vain,

was mystified in believing that the pamphlet which caused such an

immense stir at court and among the public was not the production

of the obscure man Franklin of Philadelphia, but got up among his

enemies in England and France, to rob him of his reputation. With this

belief fixed in his mind, he sat down at his desk to write a series

of letters intended to demolish the man of Philadelphia, and proving,

entirely to his own satisfaction, first, that Franklin did not exist

at all; secondly, that he had no right to exist; and thirdly, that

all his pretended discoveries were mere dreams. Not long after the

publication of his letters, the wrathful Abbé received undoubted proofs

from America that at Philadelphia there was a man called Franklin,

who himself mildly asserted his right not only to live, but to make

experiments in electricity. Poor Abbé Nollet felt his humiliation all

the more keenly as holding the post of preceptor in Natural Philosophy

to the royal family of France, and he had to suffer from a ‘burst of

inextinguishable laughter’ at one of his appearances at court.

If Count de Buffon did great service to electrical science by getting

Franklin’s pamphlet translated into French, he did still more by

instigating a series of experiments tending to verify the great theory

put forward in the pamphlet, that lightning could be drawn from the

clouds by means of pointed iron rods. By his prompting, several

gentlemen interested in scientific pursuits engaged upon trials to this

effect, among them two persons of note, M. Dalibard and M. de Lor.

The first-named had the good fortune to be successful, and thereby to

hand his name down to posterity. A wealthy man of science, M. Dalibard

was in the habit of living, during a part of the year, in a handsome

country house situated at Marly-la-Ville, about eighteen miles from

Paris, on the road to Pontoise. Marly-la-Ville stands on a high plain,

some four hundred feet above the sea-level, and the residence of M.

Dalibard being situated on the most elevated part of the ground, it

formed an excellent place for experiments, and was chosen as such by

Count de Buffon. The garden near the house was selected as the best

ground for the experiments. A wooden scaffolding was built up to hold

in its midst an iron rod, eighty feet long, and slightly over an inch

in diameter. On the top of the rod was fastened a piece of polished

steel, sharply pointed, and bronzed to prevent rust. The iron rod

entered, five feet from the ground, into another thinner one, running

horizontally towards an electrical apparatus, fastened to a table in

a kind of sentry-box, erected on purpose for observations. It was

M. Dalibard’s intention to make the experiments himself; but almost

immediately after the structure in his garden had been completed, he

was called by business to Paris, and left the whole in charge of one

of his servants, an old soldier, formerly in the French dragoons,

Coiffier by name. With true military spirit, Coiffier thought that

he ought to spend the greater part of his time in the sentry-box in

his master’s garden, and there he sat in the afternoon of Wednesday,

May 10, 1752, when a violent thunderstorm drifted over the plain

of Marly. Sufficiently instructed by his master what to do under

the circumstances, he touched the electrical apparatus with a key,

silk-bound at the handle, and to his extreme surprise, sees a flame

bursting forth. He touches another time, and there is a second flame

bursting forth, stronger than before. Then the old dragoon rushes from

his sentry-box--most famous private dragoon that ever lived, born to

the high honour of being the first man that ever drew lightning from

heaven.

It was not fear that drove the worthy servant of M. Dalibard from his

post, but a far better motive. He judged, with the prudence of an old

soldier, that the astounding things he had seen required witnesses,

in order that his master might not think him an inventor of fairy

tales. Accordingly, he hurried to the house of the prior of Marly,

M. Raulet, who lived close by, and asked him to behold the marvel of

marvels. The prior hesitated not for a moment to go, and, entering the

sentry-box, he also drew sparks from the electrical machine. Others of

the inhabitants of Marly-la-Ville, seeing the prior run, followed in

his wake, notwithstanding the rain was pouring down in streams, and

terror was struck among all of them in witnessing the dreaded lightning

creep down, serpent-like, but bereft of all its terrors, into the

sentry-box, in the centre of which stood the now exulting old dragoon.

As soon as the storm was over, the prior insisted upon Coiffier at

once saddling a horse, and riding full speed to Paris, to acquaint his

master with the great news that lightning had been drawn from the

skies by his apparatus at the blessed village of Marly-la-Ville. The

obedient dragoon did as advised, and three days after, on May 13, 1752,

M. Dalibard startled all the members of the Académie des Sciences of

Paris, convoked together in haste, by reading to them a full report of

what had taken place in the first great experiment for ascertaining the

truth of the suggestions of Benjamin Franklin.

All Europe soon rang with the report of the marvellous discovery

verified at Marly-la-Ville. But before the news of the experiment

made at the village near Paris had reached America, Benjamin Franklin

had made another, which, if not more conclusive, was at least more

original. Ever since he had arrived at his great conclusion regarding

the sameness of electricity and lightning, and the possibility of

conducting the latter to the ground harmlessly, by means of pointed

rods, the discerning citizen of Philadelphia had tried hard to find

some means for putting his ideas to a practical test, but met with

apparently insurmountable difficulties. His first plan was to set

up simply a tall iron rod near his house; but he abandoned this on

ascertaining, by measurement, that nearly all stormclouds passed over

Philadelphia, which was situated in a plain, at a height of several

hundred feet. In his then state of knowledge, he fancied that it

was impossible for him to reach the clouds in this manner. He next

resolved to await the building of an intended steeple for the principal

ecclesiastical edifice, and highest building of Philadelphia, Christ

Church. At that time not a steeple pierced the sky in all the extent

of the ‘Quaker city;’ nor was there a single one in the whole State

of Pennsylvania. But though Franklin made immense efforts to get the

steeple erected, starting a lottery for the purpose, and subscribing

largely to the funds, the work made little or no progress, many of the

principal inhabitants of the city being, from their religious opinions,

averse to the project. At last, getting impatient, Franklin’s ingenuity

hit upon the simplest of all means for verifying his great discovery.

One day he saw a boy flying a kite, and the thought instantly

occurred to him that here was the straight road from the earth to the

thunderclouds. Accordingly, he at once set to make a kite for his

intended experiments; but fearing he would incur the ridicule of his

sober fellow-citizens in engaging in what might seem to them a childish

undertaking, he kept the whole matter a profound secret. The kite he

made was not distinguished from those used by boys except of being made

of silk instead of paper so as to be able to stand the wet. Franklin

took an ordinary silk pocket-handkerchief, and fastened it over a cross

made of two light strips of cedar, by simply tying the four corners of

the handkerchief to the ends of the sticks. He next fastened a thin

iron wire, a foot long, to the top of the kite, and having provided it

with a loop and tail, attaching to the former a roll of twine, all was

ready for the experiment. Watching the skies diligently, he saw a dark

thundercloud coming up over Philadelphia late in the evening of July 4,

1752, and at once sallied forth from his house, situated at the corner

of Race and Eight streets, into a neighbouring field. There was nobody

with him but his eldest son, a lad of about twenty; and, in order to

get protection against the heavy downpour, as well as to hide from the

gaze of passers-by, the two sought shelter under an old cow-shed. Very

likely, had they been seen here at the time, the philosopher and son

might have been taken for two escaped lunatics, seeking so propitious

an occasion as a thunderstorm to fly their darling kite. Perhaps

Franklin too felt a little foolish, for he was about relinquishing his

experiment after several flashes of lightning which had not in the

least disturbed his kite, when a cloud darker than the previous one

came rolling up. All on a sudden, Franklin felt a smart shock, and saw

a spark flashing before his eyes. He had fastened the twine holding

his kite to a silk ribbon which he held in his hand, joining twine

and silk by a large key, attached to a Leyden jar. The latter at once

became heavily charged, and as shock followed upon shock, and flash

upon flash, there vanished all doubt from Franklin’s mind as to the

absolute truth of the grand discovery he had made. It may be imagined

with what inward satisfaction the great citizen of Philadelphia drew

in his kite, and crept out from under the cow-shed, when the storm was

over, and went home exultingly, the happiest of philosophers.

The experiment of Benjamin Franklin in drawing, as he thought, the

electricity of stormclouds to the ground by his kite, and thereby

demonstrating the necessity for the establishment of lightning

conductors, for the protection of persons and buildings, was accepted

as thoroughly satisfactory by the whole scientific world of Europe

at that time. Franklin was wrong, however, in supposing that the

lightning had really passed along his kite-string from the clouds to

the earth, for, had this been the case, he would undoubtedly have

been killed. What he witnessed was merely the inductive action of

the thundercloud on the kite and string. There had been some doubts

in respect to the experiment made, at the suggestion of Franklin’s

pamphlet, at Marly-la-Ville, since all the witnesses were inexperienced

persons, entirely unacquainted with the phenomena of electricity; but

there could be none whatever as regarded that tried by the originator

himself, and pronounced satisfactory by him. The fame of the wonderful

discovery spread with extraordinary swiftness through the civilized

world. Praises and congratulations flowed in upon the hitherto obscure

citizen of Philadelphia from all sides. The king of France sent him

a letter, full of compliments; the Royal Society of London voted him

their gold medal, modestly claiming a share in his work; and nearly

all the scientific bodies of France, Germany, and Italy elected him an

honorary member. But the praise of which Franklin had most reason to

be proud came from the great philosopher Immanuel Kant. The sage of

Königsberg grandly called him the modern Prometheus, bringing fire from

heaven.

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