[Illustration: JOSEPH HENRY.]
On Thursday evening, January 16, 1879, a large company gathered in the
hall of the House of Representatives at Washington. They came to honor
the memory of one of our greatest in science, since Franklin,--Joseph
Henry, the Secretary of the Smithsonian Institution. Addresses were made
by the Hon. Hannibal Hamlin, Professor Asa Gray, a most distinguished
scientist, the Hon. James A. Garfield, General W. T. Sherman, the Hon.
S. S. Cox, and others.
Not alone at the Capitol were memorial services held for Professor
Henry. Before the United States National Academy of Sciences, before the
American Association for the Advancement of Science, before the
Philosophical Society of Washington,--of all these he had been
president,--before the College of New Jersey at Princeton, where he was
Professor of Natural Philosophy for fourteen years, before the Albany
Institute, of which he was one of the original members, and before
various other societies in which he had been a leading spirit, heartfelt
testimony was given to America's loss in the death of a great scholar
and a good man.
Joseph Henry was born in Albany, N. Y., December 17, 1797, or 1799,
probably the latter date, this uncertainty arising from the illegibility
of the faded records in the old family Bible. His grandparents came from
Scotland, landing in this country June 16, 1775, the day before the
battle of Bunker Hill. The father, William Henry, of whom little is
known, died when his first son, Joseph, was nine years old. The boy had
gone two years previously to live with his maternal grandmother at
Galway, in the county of Saratoga, N. Y.
Joseph's mother is remembered as a lady of great refinement, delicate in
form and feature, and very beautiful in her youth. She was deeply
devotional, and probably to this fact is partially due Professor Henry's
earnest religious character through life.
At the district school of Galway, under Israel Phelps, Joseph exhibited
no special aptitude for books, though he showed an inquisitive mind. At
the age of ten, he was placed in a store kept by a Mr. Broderick, who
was very kind to him, allowing him to attend school in the afternoons.
His fondness for reading developed from a singular circumstance. Having
lost a pet rabbit, which had run into an opening in the foundation wall
of the village meeting-house, he crept through the hole on his hands and
knees, to find the runaway. Discovering a light through a crevice,
boy-like, he decided to investigate his surroundings. He soon reached
the vestibule of the building, and found there a book-case containing
the village library. The first book which attracted his attention was
Brooke's "Fool of Quality," a work of fiction. He began to read, and
soon forgot about his rabbit.
From this time he made frequent visits to the library, by the
underground passage, reading all the novels he could find. In the
evening, to the lads who gathered about the stove in the village store,
he rehearsed the wonderful things he had read. He was a handsome,
slender lad, of delicate complexion, vivacious manners, and a great
favorite. Mr. Broderick, the proprietor, enjoyed the stories, and
finally obtained proper access to the library for his young clerk.
When about thirteen or fourteen, Joseph was apprenticed to Mr. John F.
Doty of Albany, a watch-maker and silversmith. He found very little
pleasure in the trade, and was probably glad when, after two years, the
apprenticeship came to an end, through Mr. Doty leaving the business.
Of course he was out of work. He was very fond of the theatre, and,
having been behind the scenes, had learned how stage effects are
produced. He now joined a private theatrical company, called "The
Rostrum," and was soon made president of the society. He dramatized a
story, and wrote a comedy, both of which were acted. He seemed destined
to become an actor, probably not with the approval of his Scotch
Presbyterian mother.
Lives are sometimes changed by seemingly trivial events, yet nothing is
trivial that influences a human being. Garfield said, "To every man of
great original power there comes, in early youth, a moment of sudden
discovery--of self-recognition--when his own nature is revealed to
himself, when he catches for the first time a strain of that immortal
song to which his own spirit answers, and which becomes thenceforth and
forever the inspiration of his life.
"'Like noble music unto noble words.'"
That "moment of sudden discovery" came to Henry at sixteen. A slight
accident had confined him to his mother's house for a few days. A young
Scotch gentleman, Robert Boyle, who was boarding with her, had left upon
the table of his chamber an unostentatious book, "Lectures on
Experimental Philosophy, Astronomy, and Chemistry: by G. Gregory, D.D.,
Vicar of Westham."
The book begins by asking several questions: "You throw a stone, or
shoot an arrow into the air; why does it not go forward in the line or
direction that you give it? Why does it stop at a certain distance, and
then return to you?... On the contrary, why does flame or smoke always
mount upward, though no force is used to send them in that direction?
And why should not the flame of a candle drop toward the floor when you
reverse it, or hold it downward, instead of turning up and ascending
into the air?... Again, you look into a clear well of water, and see
your own face and figure, as if painted there. Why is this? You are
told that it is done by reflection of light. But what is reflection of
light?"
Henry took up this book and began to read. Soon it seemed more
interesting than Brooke's "Fool of Quality" and all the romances. At the
very next meeting of the theatrical society, he resigned the presidency,
telling his companions that he should devote his life to solid studies.
Robert Boyle, seeing that the youth was interested in the book, gave it
to him. It was ever after preserved in Professor Henry's library, with
these words written on the fly-leaf: "This book, although by no means a
profound work, has, under Providence, exerted a remarkable influence
upon my life. It accidentally fell into my hands when I was about
sixteen years old, and was the first work I ever read with attention. It
opened to me a new world of thought and enjoyment; invested things
before almost unnoticed with the highest interest; fixed my mind on the
study of nature, and caused me to resolve, at the time of reading it,
that I would immediately commence to devote my life to the acquisition
of knowledge."
This resolution was at once put in practice, by attending a
night-school, where he soon learned all that the master could teach. His
next attempt at education was to learn grammar of a travelling teacher,
and so skilled did he become that he made a grammatical tour of the
country districts, in imitation of his instructor, earning enough money
to enter the Albany Academy. When more money was needed, the
enterprising youth found a situation as head of a district school, at
eight dollars a month! He pleased his patrons so well that he received
fifteen dollars for the second month. Later, he became an assistant in
the academy, while still a pupil.
Says Orlando Meads, LL.D.: "When a boy in the Albany Academy in 1823 and
1824, it was my pleasure and privilege, when released from recitations,
to resort to the chemical laboratory and lecture room. There might be
found from day to day through the winter, earnestly engaged in
experiments upon steam and upon a small steam-engine, and in chemical
and other scientific investigations, two young men--both active members
of the 'Lyceum,' then very different in their external circumstances and
prospects in life, but of kindred tastes and sympathies; the one was
Richard Varick De Witt, the other was Joseph Henry, as yet unknown to
fame, but already giving promise of those rare qualities of mind and
character which have since raised him to the very first rank among the
experimental philosophers of his time.
"Chemistry at that time was exciting great interest, and Dr. Beck's
courses of chemical lectures, conducted every winter in the lecture room
of the academy, were attended not only by the students, but by all that
was most intelligent and fashionable in the city. Henry ... was then Dr.
Beck's chemical assistant, and already an admirable experimentalist,
and he availed himself to the utmost of the advantages thus afforded of
prosecuting his investigations in chemistry, electricity, and
galvanism." Dr. T. Romeyn Beck, the principal, had become interested in
the studious young man, and, when he left the academy, recommended him
to one of the trustees, General Stephen Van Rensselaer, as a private
tutor to his sons. Young Henry's services were engaged, and, as his
teaching required but about three hours each day, he devoted his leisure
to higher mathematics, in conjunction with chemistry, physiology, and
anatomy, as he had decided to become a physician. In his mathematical
studies he went so far as to read the _Mecanique Analytique_ of La
Grange.
His delicate constitution seemed unable to bear the continued strain of
study and teaching, and at twenty-six, through the friendship of an
influential judge, Henry received the appointment of engineer in the
survey of a road between the Hudson River and Lake Erie, a distance of
about three hundred miles. This gave him out-of-door life, which he
needed, and, though much of his work was done in winter, in deep snow,
making his way through dense forests, he entirely regained his health,
and gave such excellent satisfaction that he was asked to construct a
canal in Ohio, and assist in a mining enterprise in Mexico. Both of
these he refused, accepting the chair of Mathematics and Natural
Philosophy in the Albany Academy, at the urgent solicitation of his
friend, Dr. Beck.
Elected in the spring, and not entering upon his work till autumn, he
spent the intervening months in geological exploration in New York
State. Every hour was occupied. He had commenced solid study in earnest,
as he had told the members of the "Rostrum" he should do.
Having entered upon his profession, he taught mathematics seven hours
daily. But he found time to make experiments in natural philosophy. The
first paper which he brought before the Albany Institute was, "On the
Chemical and Mechanical Effects of Steam: with Experiments designed to
illustrate the Great Reduction of Temperature in Steam of High
Elasticity when suddenly expanded."
His next published scientific paper was, "On the Production of Cold by
the Rarefaction of Air: accompanied by Experiments." "One of these
experiments most strikingly illustrated the great reduction of
temperature which takes place on the sudden rarefaction of condensed
air. Half a pint of water was poured into a strong copper vessel of a
globular form, and having a capacity of five gallons; a tube of
one-fourth of an inch caliber, with a number of holes near the lower
end, and a stop-cock attached to the other extremity, was firmly screwed
into the neck of the vessel; the lower end of the tube dipped into the
water, but a number of holes were above the surface of the liquid, so
that a jet of air mingled with water might be thrown from the fountain.
"The apparatus was then charged with condensed air, by means of a
powerful condensing pump, until the pressure was estimated at nine
atmospheres. During the condensation, the vessel became sensibly warm.
After suffering the apparatus to cool down to the temperature of the
room, the stop-cock was opened: the air rushed out with great violence,
carrying with it a quantity of water, which was instantly converted into
snow. After a few seconds, the tube became filled with ice, which almost
entirely stopped the current of air. The neck of the vessel was then
partially unscrewed, so as to allow the condensed air to rush out around
the sides of the screw; in this state the temperature of the whole
interior atmosphere was so much reduced as to freeze the remaining water
in the vessel."
Other pamphlets followed this publication, but in 1831 a notable paper
in the "American Journal of Science and the Arts" brought Henry's name
to the front line of discoverers in electro-magnetism. Sturgeon made the
first electro-magnet; Henry made the electro-magnet what it is.
Says W. B. Taylor, in an address before the "Philosophical Society of
Washington:" "The electro-magnet figured and described by Sturgeon
consisted of a small bar or stout iron wire bent into a [Inverted
U-Symbol] or horse-shoe form, having a copper wire wound loosely
around it in eighteen turns, with the ends of the wire dipping into
mercury-cups connected with the respective poles of a battery having
one hundred and thirty square inches of active surface."
Henry improved upon this in 1828, but in March of 1829 he exhibited
before the Institute a somewhat larger magnet. "A round piece of iron
about one-quarter of an inch in diameter was bent into the usual form of
a horse-shoe, and, instead of loosely coiling around it a few feet of
wire as is usually described, it was tightly wound with thirty-five feet
of wire covered with silk, so as to form about four hundred turns; a
pair of small galvanic plates, which could be dipped into a tumbler of
diluted acid, was soldered to the ends of the wire, and the whole
mounted on a stand. With these small plates, the horse-shoe became much
more powerfully magnetic than another of the same size and wound in the
usual manner, by the application of a battery composed of twenty-eight
plates of copper and zinc each eight inches square."
"To Henry, therefore," says Mr. Taylor, "belongs the exclusive credit of
having first constructed the magnetic 'spool' or 'bobbin,' that form of
coil since universally employed for every application of
electro-magnetism, of induction, or of magneto-electrics. This was his
first great contribution to the science and to the art of galvanic
magnetization....
"But, in addition to this large gift to science, Henry has the
preeminent claim to popular gratitude of having first practically
worked out the differing functions of two entirely different kinds
of electro-magnet; the one surrounded with numerous coils of no great
length, designated by him the 'quantity' magnet, the other surrounded
with a continuous coil of very great length, designated by him the
'intensity' magnet.... Never should it be forgotten that he who first
exalted the 'quantity' magnet of Sturgeon from a power of twenty pounds
to a power of twenty hundred pounds was the absolute CREATOR of the
'intensity' magnet; and that the principles involved in this creation
constitute the indispensable basis of every form of the electro-magnetic
telegraph since invented."
Professor Silliman of Yale College said: "Henry has the honor of having
constructed by far the most powerful magnets that have ever been known;
and his last, weighing (armature and all) but 82-1/2 pounds, sustains
over a ton;--which is eight times more powerful than any magnet hitherto
known in Europe."
"In 1831," says Professor Henry, "I arranged around one of the upper
rooms of the Albany Academy a wire of more than a mile in length,
through which I was enabled to make signals by sounding a bell. The
mechanical arrangement for effecting this object was simply a steel bar,
permanently magnetized, of about ten inches in length, supported on a
pivot, and placed with its north end between the two arms of a
horse-shoe magnet. When the latter was excited by the current, the end
of the bar thus placed was attracted by one arm of the horse-shoe and
repelled by the other, and was thus caused to move in a horizontal plane
and its further end to strike a bell suitably adjusted." This was the
first "sounding" electro-magnetic telegraph. With this growing fame he
was not disposed to think too highly of himself. A friend, noticing a
look of sadness in the face of the young professor, said to
him,--"Albany will one day be proud of her son;" and so it proved.
A year before this, in May, 1830, Professor Henry had married, at
thirty-one, Harriet L. Alexander of Schenectady, N. Y., a cultivated and
helpful woman.
In 1832, Princeton College needed a professor of natural philosophy.
Henry's friends heartily commended him for the position. Silliman
said,--"Henry has no superior among the scientific men of the country,"
and Professor Renwick of Columbia College, New York, said, "He has no
equal."
After six years at the Albany Academy, Henry removed to Princeton, where
for fourteen years he added constantly to his fame and usefulness by
original work. Of his discoveries in these fruitful years he gives the
following summary, at the request of a friend:--
"I arrived in Princeton in November, 1832, and, as soon as I became
fully settled in the chair which I occupied, I recommenced my
investigations, constructed a still more powerful electro-magnet than I
had made before,--one which would sustain over three thousand
pounds,--and with it illustrated to my class the manner in which a large
amount of power might, by means of a relay magnet, be called into
operation at the distance of many miles.... The electro-magnetic
telegraph was first invented by me, in Albany, in 1830.... At the time
of making my original experiments on electro-magnetism in Albany, I was
urged by a friend to take out a patent, both for its application to
machinery and to the telegraph; but this I declined, on the ground that
I did not then consider it compatible with the dignity of science to
confine the benefits which might be derived from it to the exclusive use
of any individual. In this perhaps I was too fastidious."
Professor Asa Gray well said, "For the telegraph and for
electro-magnetic machines, what was now wanted was not discovery, but
invention; not the ascertainment of principles, but the devising of
methods." Morse is not to be less honored because somebody discovered
the principle, which he and others utilized for the race, any more than
Edison, Bell, and others, because Faraday and Henry helped to make their
grand work possible.
"My next investigation, after being settled at Princeton," says
Professor Henry, "was in relation to electro-dynamic induction. Mr.
Faraday had discovered that when a current of galvanic electricity was
passed through a wire from a battery, a current in an opposite direction
was induced in a wire arranged parallel to this conductor. I discovered
that an induction of a similar kind took place in the primary conducting
wire itself, so that a current which, in its passage through a short
wire conductor, would neither produce sparks nor shocks would, if the
wire were sufficiently long, produce both those phenomena....
"A series of investigations was afterwards made, resulting in producing
inductive currents of different orders, having different directions,
made up of waves alternately in opposite directions....
"Another series of investigations, of a parallel character, was made in
regard to ordinary or frictional electricity. In the course of these it
was shown that electro-dynamic inductive action of ordinary electricity
was of a peculiar character, and that effects could be produced by it at
a remarkable distance. For example, if a shock were sent through a wire
on the outside of a building, electrical effects could be exhibited in a
parallel wire within the building."...
After this, investigations were made in atmospheric induction; induction
from thunder clouds; in regard to lightning rods; on substances capable
of exhibiting phosphorescence, such as the diamond, which, when exposed
to the direct rays of the sun, and then removed to a dark place, emits a
pale blue light; on a method of determining the velocity of projectiles;
on the heat of the spots on the sun as compared with the rest of his
disk; the detection of heat by the thermal telescope--"when the object
was a horse in a distant field, the radiant heat from the animal was
distinctly perceptible at a distance of at least several hundred yards;"
on the cohesion of liquids; on the tenacity of soapwater in films; on
the origin of mechanical power, and the nature of vital force.