be of use to mankind, in preserving houses, churches, ships, &c., from
the stroke of lightning, by directing us to fix, on the highest parts of
these edifices, upright rods of iron made sharp as a needle, and gilded
to prevent rusting, and from the foot of those rods a wire down the
outside of the building into the ground, or down round one of the
shrouds of a ship, and down her side till it reaches the water? Would
not these pointed rods probably draw the electrical fire silently out of
a cloud before it came nigh enough to strike, and thereby secure us from
that most sudden and terrible mischief?
"To determine the question whether the clouds that contain lightning are
electrified or not, I would propose an experiment to be tried where it
may be done conveniently. On the top of some high tower or steeple,
place a kind of sentry-box, big enough to contain a man and an
electrical stand. From the middle of the stand let an iron rod rise and
pass bending out of the door and then upright twenty or thirty feet,
pointed very sharp at the end. If the electrical stand be kept clean and
dry, a man standing on it, when such clouds are passing low, might be
electrified and afford sparks, the rod drawing fire to him from a cloud.
If any danger to the man should be apprehended (though I think there
would be none), let him stand on the floor of his box, and now and then
bring near to the rod the loop of a wire that has one end fastened to
the leads, he holding it by a wax handle; so the sparks, if the rod is
electrified, will strike from the rod to the wire, and not affect him."
The Royal Society "did not think these papers worth printing"!
But, happily, Collinson printed them, and they went all over Europe. The
demonstration of the lightning theory, which he had wrought out by his
own experiments, was made in France, May 10, 1752; and in Philadelphia
by Franklin with the kite in the next month, before he had heard of the
success in France. Franklin's friend Dalibard tried the French
experiment. Here is his account of it, as he sent it to the French
Academy, as Roxana translated it for the young people:--
I have had perfect success in following out the course indicated by Mr.
Franklin.
I had set up at Marly-la-ville, situated six leagues from Paris, in a
fine plain at a very elevated level, a round rod of iron, about an inch
in diameter, forty feet long, and sharply pointed at its upper
extremity. To secure greater fineness at the point, I had it armed with
tempered steel, and then burnished, for want of gilding, so as to keep
it from rusting; beside that, this iron rod is bent near its lower end
into two acute but rounded angles; the first angle is two feet from the
lower end, and the second takes a contrary direction at three feet from
the first.
* * * * *
Wednesday, the 10th of May, 1752, between two and three in the
afternoon, a man named Coiffier, an old dragoon, whom I had intrusted
with making the observations in my absence, having heard rather a loud
clap of thunder, hastened at once to the machine, took the phial with
the wire, presented the loop of the wire to the rod, saw a small bright
spark come from it, and heard it crackle. He then drew a second spark,
brighter than the first and with a louder sound! He called his
neighbors, and sent for the Prior. This gentleman hastened to the spot
as fast as he could: the parishioners, seeing the haste of their priest,
imagined that poor Coiffier had been killed by the thunder; the alarm
was spread in the village; the hail-storm which began did not prevent
the flock from following its shepherd. This honest priest approached the
machine, and, seeing that there was no danger, went to work himself and
drew strong sparks. The cloud from which the storm and hail came was no
more than a quarter of an hour in passing directly over our machine, and
only this one thunder-clap was heard. As soon as the cloud had passed,
and no more sparks were drawn from the iron rod, the Prior of Marly sent
off Monsieur Coiffier himself, to bring me the following letter, which
he wrote in haste:--
I can now inform you, Sir, of what you are looking for. The experiment
is completely successful. To-day, at twenty minutes past two, P. M., the
thunder rolled directly over Marly; the clap was rather loud. The
desire to oblige you, and my own curiosity, made me leave my arm-chair,
where I was occupied in reading. I went to Coiffier's, who had already
sent a child to me, whom I met on the way, to beg me to come. I
redoubled my speed through a torrent of hail. When I arrived at the
place where the bent rod was set up, I presented the wire, approaching
it several times toward the rod. At the distance of an inch and a half,
or about that, there came out of the rod a little column of bluish fire
smelling of sulphur, which struck the loop of the wire with an extreme
and rapid energy, and occasioned a sound like that which might be made
by striking on the rod with a key. I repeated the experiment at least
six times, in the space of about four minutes, in the presence of
several persons; and each experiment which I made lasted the space of a
_Pater_ and an _Ave_. I tried to go on; the action of the fire slackened
little by little. I went nearer, and drew nothing more but a few sparks,
and at last nothing appeared.
The thunder-clap which caused this event was followed by no other; it
all ended in a great quantity of hail. I was so occupied with what I saw
at the moment of the experiment, that, having been struck on the arm a
little above my elbow, I cannot say whether it was in touching the wire
or the rod, I was not even aware of the injury which the blow had given
me at the moment when I received it; but as the pain continued, on my
return home I uncovered my arm before Coiffier, and we perceived a
bruised mark winding round the arm, like what a wire would have made if
my bare flesh had been struck by it. As I was going back from Coiffier's
house, I met Monsieur le Vicaire, Monsieur de Milly, and the
schoolmaster, to whom I related what had just happened. They all three
declared that they smelt an odor of sulphur, which struck them more as
they approached me. I carried the same odor home with me, and my
servants noticed it without my having said anything to them about it.
This, Monsieur, is an account given in haste, but simple and true, which
I attest, and you may depend on my being ready to give evidence of this
event on every opportunity. Coiffier was the first who made the
experiment, and repeated it several times; it was only on account of
what he had seen that he sent to ask me to come. If other witnesses than
he and I are necessary, you will find them. Coiffier is in haste to set
out.
I am, with respectful consideration, Monsieur,
Yours, &c.,
[Signed] RAULET, _Prior of Marly_.
MAY 10, 1752.
"I do not understand," said Uncle Fritz, "how it happened that no one
attempted the experiment before. Franklin had proposed it, very
distinctly, in 1750. His friend Dr. Stuber says that he was waiting for
the erection of a steeple in Philadelphia. You see, the Quakers, who had
founded this city, would have none; they derided what they called
'steeple-houses,' little foreseeing what advantage could be drawn from a
steeple.
"Meanwhile, in 1750, in October, he did take a view of New York from the
'Dutch Church steeple,' which had been struck by lightning in the spring
of that year. And here he was able to confirm his theory, by seeing that
'wire is a good conductor of lightning, as it is of electricity.'"
MUSICAL GLASSES.
While some of the children were reading these electrical passages,
others were turning over the next volume; and to their great delight,
they found a picture of the "Musical Glasses."
"I never had the slightest idea what musical glasses were," said Jack;
and he spouted from Goldsmith the passage from "The Vicar of Wakefield,"
where the fashionable ladies from London talked about "Shakspeare and
the musical glasses."
"Were they Dr. Franklin's musical glasses?"
"I never thought of that," said Uncle Fritz, well pleased; "but I think
it is so. John, look and see what year 'The Vicar of Wakefield' was
written in."
John turned to the Cyclopædia, and it proved that Goldsmith wrote that
book in 1766.
"And you see," said Uncle Fritz, "that it was in 1762 that Franklin made
his improvement, and that Mr. Puckeridge, the Irish gentleman, had
arranged his glasses before. I think you would find that the instrument
gradually worked its way into fashion,--slowly, as such things then did
in England,--and that Goldsmith knew about Dr. Franklin's modification.
"I do not now remember any other place where Goldsmith's life and his
touched. But they must have known a great many of the same people.
Franklin was all mixed up with the Grub Street people."
Meanwhile John was following up the matter in the Cyclopædia. But he did
not find "Armonica." Uncle Fritz bade him try in the "H" volume; and
there, sure enough, was "Harmonica," with quite a little history of the
invention. Mr. Puckeridge's fascinating name is there tamed down to
Pochrich, probably by some German translator. Dr. Franklin's instrument
is described, and the Cyclopædia man adds:--
"From the effect which it was supposed to have upon the nervous system,
it has been suggested that the fingers should not be allowed to come in
immediate contact with the glasses, but that the tones should be
produced by means of keys, as with a harpsichord. Such an instrument has
been made, and called the '_harpsichord harmonica_.' But these
experiments have not produced anything of much value. It is impossible
that the delicacy, the swell, and the continuation of the tone should be
carried to such perfection as in the simpler method. The harmonica,
however much it excels all other instruments in the delicacy and
duration of its tones, yet is confined to those of a soft and melancholy
character and to slow, solemn movements, and can hardly be combined to
advantage with other instruments. In accompanying the human voice it
throws it into the shade; and in concerts the other instruments lose in
effect, because so far inferior to it in tone. It is therefore best
enjoyed by itself, and may produce a charming effect in certain romantic
situations."
"'Romantic situations'! I should think so," said Mabel, laughing. "Is
not that like the dear German man that wrote this? I see myself lugging
my harmonica to the edge of the Kauterskill Falls."
"How do you know he was a German?" said Alice.
"Because, where John read 'the simpler method,' it says 'the
before-mentioned method.' No Englishman or American in his senses ever
said 'before-mentioned' if he could help himself."
"Do let us see how dear Dr. Franklin made his machine."
And the girls unfolded the old-fashioned picture, which is in the sixth
volume of Sparks's Franklin, and read his description of it as he wrote
it to Beccaria.
"Is it the Beccaria who did about capital punishment?" asked Fergus.
"No," Uncle Fritz said, "though they lived at the same time. They were
not brothers. The capital-punishment man was the Marquis _of_ Beccaria,
and that _of_ makes a great difference in Europe. This man 'did'
electricity, as you would say; and his name is plain Beccaria without
any _of_."
Then Mabel, commanding silence, at last read the letter to Beccaria. And
when she had done, Uncle Fritz said that he should think there might be
many a boy or girl who could not buy a piano or what he profanely called
a Yang-Yang,--by which he meant a reed organ,--who would like to make a
harmonica. The letter, in a part not copied here, tells how to tune the
glasses. And any one who lived near a glass-factory, and was on the
good-natured side of a good workman, could have the glasses made without
much expense.
_Letter of Franklin to J. B. Beccaria._
LONDON, July 13, 1762.
REVEREND SIR,--... Perhaps, however, it may be agreeable to you, as you
live in a musical country, to have an account of the new instrument
lately added here to the great number that charming science was already
possessed of. As it is an instrument that seems peculiarly adapted to
Italian music, especially that of the soft and plaintive kind, I will
endeavor to give you such a description of it, and of the manner of
constructing it, that you or any of your friends may be enabled to
imitate it, if you incline so to do, without being at the expense and
trouble I have been to bring it to its present perfection.
You have doubtless heard of the sweet tone that is drawn from a
drinking-glass by passing a wet finger round its brim. One Mr.
Puckeridge, a gentleman from Ireland, was the first who thought of
playing tunes formed of these tones. He collected a number of glasses of
different sizes, fixed them near each other on a table, tuned them by
putting into them water more or less, as each note required. The tones
were brought out by passing his finger round their brims. He was
unfortunately burned here, with his instrument, in a fire which consumed
the house he lived in. Mr. E. Delaval, a most ingenious member of our
Royal Society, made one in imitation of it, with a better form and
choice of glasses, which was the first I saw or heard. Being charmed by
the sweetness of its tones, and the music he produced from it, I wished
only to see the glasses disposed in a more convenient form, and brought
together in a narrower compass, so as to admit of a greater number of
tones, and all within reach of hand to a person sitting before the
instrument, which I accomplished, after various intermediate trials, and
less commodious forms, both of glasses and construction, in the
following manner.
The glasses are blown as nearly as possible in the form of hemispheres,
having each an open neck or socket in the middle. The thickness of the
glass near the brim about a tenth of an inch, or hardly quite so much,
but thicker as it comes nearer the neck, which in the largest glasses is
about an inch deep, and an inch and a half wide within, these dimensions
lessening as the glasses themselves diminish in size, except that the
neck of the smallest ought not to be shorter than half an inch. The
largest glass is nine inches diameter, and the smallest three inches.
Between these two are twenty-three different sizes, differing from each
other a quarter of an inch in diameter. To make a single instrument
there should be at least six glasses blown of each size; and out of this
number one may probably pick thirty-seven glasses (which are sufficient
for three octaves with all the semitones) that will be each either the
note one wants or a little sharper than that note, and all fitting so
well into each other as to taper pretty regularly from the largest to
the smallest. It is true there are not thirty-seven sizes, but it often
happens that two of the same size differ a note or half-note in tone, by
reason of a difference in thickness, and these may be placed one in the
other without sensibly hurting the regularity of the taper form.
The glasses being thus turned, you are to be provided with a case for
them, and a spindle on which they are to be fixed. My case is about
three feet long, eleven inches every way wide at the biggest end; for it
tapers all the way, to adapt it better to the conical figure of the set
of glasses. This case opens in the middle of its height, and the upper
part turns up by hinges fixed behind. The spindle, which is of hard
iron, lies horizontally from end to end of the box within, exactly in
the middle, and is made to turn on brass gudgeons at each end. It is
round, an inch in diameter at the thickest end, and tapering to a
quarter of an inch at the smallest. A square shank comes from its
thickest end through the box, on which shank a wheel is fixed by a
screw. This wheel serves as a fly to make the motion equable, when the
spindle with the glasses is turned by the foot like a spinning-wheel.
My wheel is of mahogany, eighteen inches diameter, and pretty thick, so
as to conceal near its circumference about twenty-five pounds of lead.
An ivory pin is fixed in the face of this wheel, and about four inches
from the axis. Over the neck of this pin is put the loop of the string
that comes up from the movable step to give it motion. The case stands
on a neat frame with four legs.
To fix the glasses on the spindle, a cork is first to be fitted in each
neck pretty tight, and projecting a little without the neck, that the
neck of one may not touch the inside of another when put together, for
that would make a jarring. These corks are to be perforated with holes
of different diameters, so as to suit that part of the spindle on which
they are to be fixed. When a glass is put on, by holding it stiffly
between both hands, while another turns the spindle, it may be gradually
brought to its place. But care must be taken that the hole be not too
small, lest, in forcing it up, the neck should split; nor too large,
lest the glass, not being firmly fixed, should turn or move on the
spindle, so as to touch or jar against its neighboring glass. The
glasses are thus placed one in another, the largest on the biggest end
of the spindle, which is to the left hand; the neck of this glass is
towards the wheel, and the next goes into it in the same position, only
about an inch of its brim appearing beyond the brim of the first; thus
proceeding, every glass when fixed shows about an inch of its brim (or
three quarters of an inch, or half an inch, as they grow smaller) beyond
the brim of the glass that contains it; and it is from these exposed
parts of each glass that the tone is drawn, by laying a finger upon one
of them as the spindle and glasses turn round.
My largest glass is G, a little below the reach of a common voice, and
my highest G, including three complete octaves. To distinguish the
glasses the more readily to the eye, I have painted the apparent parts
of the glasses withinside, every semitone white, and the other notes of
the octave with the seven prismatic colors,--viz., C, red; D, orange; E,
yellow; F, green; G, blue; A, indigo; B, purple; and C, red again,--so
that glasses of the same color (the white excepted) are always octaves
to each other.
This instrument is played upon by sitting before the middle of the set
of glasses, as before the keys of a harpsichord, turning them with the
foot, and wetting them now and then with a sponge and clean water. The
fingers should be first a little soaked in water, and quite free from
all greasiness; a little fine chalk upon them is sometimes useful, to
make them catch the glass and bring out the tone more readily. Both
hands are used, by which means different parts are played together.
Observe that the tones are best brought out when the glasses turn _from_
the ends of the fingers, not when they turn _to_ them.
The advantages of this instrument are, that its tones are incomparably
sweet, beyond those of any other; that they may be swelled and softened
at pleasure by stronger or weaker pressure of the finger, and continued
to any length; and that the instrument, being once well tuned, never
again wants tuning.
In honor of your musical language, I have borrowed from it the name of
this instrument, calling it the Armonica.
With great respect and esteem, I am, &c.,
B. FRANKLIN.
VII.
THEORISTS OF THE EIGHTEENTH CENTURY.
RICHARD LOVELL EDGEWORTH.
At the next meeting there was a slight deviation from the absolutely
expected. Bedford and Mabel desired to dispense with the regular order
of the day, and moved for permission to bring in a new inventor,
"invented by myself," said Mabel,--"entirely by myself, assisted by
Bedford. Nobody that I know of ever heard of him before. He is a new
discovery."
"Who is he?" asked Horace, somewhat piqued that there should be any one
interesting of whom he had not heard even the name.
"What did he invent?" asked Emma.
"Did he write memoirs?" asked Fergus.
"Did you ever read 'Frank'?" asked Mabel, in what is known as the
Socratic method.
There was a slight stir at the mention of this little classic. Few
seemed to be able to answer in the affirmative.
"I have read 'Rollo,'" said Horace.
"I have read 'Frank,'" said Will Withers, "and 'Harry and Lucy,' and the
'Parents' Assistant,' and 'Sandford and Merton,' and 'Henry Milner.' In
fact, there are few of those books, all kindred volumes, which I have
not read. They have had an important effect upon my later life."
"Hinc illae lachrymae," in a low tone from Clem Waters.
For Colonel Ingham, the turn taken by the conversation had a peculiar
charm. He was of the generation before the rest, and what were to them
but ghostly ideals were to him glad memories of a happy past.
"Good!" said he. "'Frank' was, in a sense, the greatest book ever
written. Do you remember that part where Frank lifted up the skirts of
his coat when passing through the greenhouse?" he asked of Mabel.
"I should think I did," said Mabel and Will. As for Bedford, he had only
a vague recollection of it. The others considered the conversation to be
trembling upon the verge of insanity.
"Perhaps," said Florence, gently, "I might be allowed to suggest that
although you have heard of 'Frank' and those other persons mentioned, we
have not. I do not think that I ever heard of an inventor named
Frank,--did he have any other name?--and I am usually considered," she
went on modestly, "tolerably well informed. Therefore the present
conversation, though probably edifying in a high degree to those who
have read 'Frank,' or who have some interest in horticulture and
greenhouses, can hardly fail to be very stupid to those of us who have
not."
"My dear child," said the Colonel, "you are right. Mabel and I, and Will
and Bedford here, are of the generation that is passing off the stage.
We look back to the things of our youth, hardly considering that there
are those to whom that period suggests Noah and his ark."
"But who is the inventor?" asked some one who thought that the
conversation was gradually leaving the trodden path.
"Oh, we had almost forgotten him," said Bedford.
"The inventor," said Mabel, producing two volumes from under her arm,
"is Mr. Richard Lovell Edgeworth, the father of Maria Edgeworth."
"What did he invent?" asked many of the company.
"He invented the telegraph."
"Well, I never knew that before."
"I thought Morse invented the telegraph."
"Didn't Dr. Franklin invent the telegraph?"
"I thought Edison--"
Other remarks were also made, showing a certain amount of incredulity.
"You mistake," said Bedford, placidly; "you are all of you under a
misapprehension. I think that you all of you allude to the electric
telegraph,--an invention of a later date than that of Mr. Edgeworth, and
one of more value, as far as practical affairs are concerned. No; Mr.
Edgeworth invented, or thinks he invented, the telegraph as it was used
in the eighteenth century and the early part of the nineteenth,
sometimes named the Semaphore. It wasn't a difficult invention, and I
don't believe it ever came to any very practical use as constructed by
Edgeworth, though French telegraphs were very useful."
"What kind of a telegraph was it?"
"Well, it was just the kind of a telegraph that the conductor of a
railroad train is when he waves his arms to the engineer to go ahead.
There's an account of it by Edgeworth in one of these books, with
pictures to it."
"But my chief interest about Edgeworth," said Mabel, "is in his memoirs,
which are written partly by himself and partly by his daughter. They are
really very amusing. He was married five times,--once with a door-key
when he was only fourteen."
This startling intelligence roused even Colonel Ingham to demand
particulars. Was he married to all five at once? to all of them when he
was only fourteen?
"No," admitted Mabel, with some regret; "he was married to them, all at
different times, and he was divorced from the one he married at fourteen
with the door-key."
"They were only married for fun," said Bedford. "It was all a joke. They
were at a wedding, and they thought it would be funny after the real
marriage to have a mock one. So they did, and married Edgeworth to a
girl who was there. It was a real marriage, for they were afterwards
divorced."
"Well," said Sam Edmeston, "I shall be glad to hear about this
gentleman, I'm sure, though I never did hear of him before. But may I
ask why it was necessary to introduce him by means of an allusion to
'Frank' and other works which we have few of us ever read, though it is
very possible that we may some of us have heard of them?"