stamp, and conscious of his own capability to produce it, he labored for
some months to accomplish his object, feeling sure that, if successful,
he would be amply rewarded by the Government. To insure the secrecy of
his experiments, he worked at them during the night, after his ordinary
business of the day was over. He succeeded at last in making a stamp
which obviated the great objection to the then existing form, inasmuch
as it would be impossible to transfer it from one deed to another, to
obliterate it by moisture, or to take an impression from it capable of
producing a duplicate. Flushed with success and confident of the reward
of his labors, he waited upon Sir Charles Persley at Somerset House, and
showed him, by numerous proofs, how easily all the then existing stamps
could be forged, and his new invention to prevent forgery. Sir Charles,
who was much astonished at the one invention and pleased with the other,
asked Bessemer to call again in a few days. At the second interview Sir
Charles asked him to work out the principle of the new stamping
invention more fully. Accordingly Bessemer devoted five or six weeks'
more labor to the perfecting of his stamp, with which the Stamp Office
authorities were now well pleased. The design, as described by the
inventor, was circular, about two and a half inches in diameter, and
consisted of a garter with a motto in capital letters, surmounted by a
crown. Within the garter was a shield, and the garter was filled with
network in imitation of lace. The die was executed in steel, which
pierced the parchment with more than four hundred holes; and these holes
formed the stamp. It is by a similar process that valentine makers have
since learned to make the perforated paper used in their trade. Such a
stamp removed all the objections to the old one. So pleased was Sir
Charles with it that he recommended it to Lord Althorp, and it was soon
adopted by the Stamp Office. At the same time Sir Henry was asked
whether he would be satisfied with the position of Superintendent of
Stamps with £500 or £600 per annum, as compensation for his invention,
instead of a sum of money from the treasury. This appointment he gladly
agreed to accept; for, being engaged to be married at the time, he
thought his future position in life was settled. Shortly afterwards he
called on the young lady to whom he was engaged, and communicated the
glad tidings to her, at the same time showing her the design of his new
stamp. On explaining to her that its chief virtue was that the new
stamps thus produced could not, like the old ones, be fraudulently used
twice or thrice, she instantly suggested that if all stamps had a date
put upon them they could not be used at a future time without detection.
The idea was new to him; and, impressed with its practical character, he
at once conceived a plan for the insertion of movable dates in the die
of his stamp. The method by which this is now done is too well known to
require description here; but in 1833 it was a new invention. Having
worked out the details of a stamp with movable dates, he saw that it
was more simple and more easily worked than his elaborate die for
perforating stamps; but he also saw that if he disclosed his latest
invention it might interfere with his settled prospects in connection
with the carrying out of his first one. It was not without regret, too,
that he saw the results of many months of toil and the experiments of
many lonely nights at once superseded; but his conviction of the
superiority of his latest design was so strong, and his own sense of
honor and his confidence in that of the Government was so unsuspecting,
that he boldly went and placed the whole matter before Sir Charles
Persley. Of course the new design was preferred. Sir Charles truly
observed that with this new plan all the old dies, old presses, and old
workmen could be employed. Among the other advantages it presented to
the Government, it did not fail to strike Sir Charles that no
Superintendent of Stamps would now be necessary,--a recommendation which
the perforated die did not possess. The Stamp Office therefore abandoned
the ingenuous and ingenious inventor. The old stamps were called in, and
the new ones issued in a few weeks; the revenue from stamps grew
enormously, and forged or feloniously used stamps are now almost unheard
of. The Stamp Office reaped a benefit which it is scarcely possible to
estimate fully, while Bessemer did not receive a farthing. Shortly after
the new stamp was adopted by Act of Parliament, Lord Althorp resigned,
and his successors disclaimed all liability. When the disappointed
inventor pressed his claim, he was met by all sorts of half-promises and
excuses, which ended in nothing. The disappointment was all the more
galling because, if Bessemer had stuck to his first-adopted plan, his
services would have been indispensable to its execution; and it was
therefore through his putting a better and more easily worked plan
before them that his services were coolly ignored. "I had no patent to
fall back upon," he says, in describing the incident afterward. "I could
not go to law, even if I wished to do so; for I was reminded, when
pressing for mere money out of pocket, that I had done all the work
voluntarily and of my own accord. Wearied and disgusted, I at last
ceased to waste time in calling at the Stamp Office,--for time was
precious to me in those days,--and I felt that nothing but increased
exertions could make up for the loss of some nine months of toil and
expenditure. Thus sad and dispirited, and with a burning sense of
injustice overpowering all other feelings, I went my way from the Stamp
Office, too proud to ask as a favor that which was indubitably my
right."
GOLD PAINT.
Shortly after he had taken out his first patent for his improvement in
type-founding, his attention was accidentally turned to the manufacture
of bronze powder, which is used in gold-work, japanning, gold-printing,
and similar operations. While engaged in ornamenting a vignette in his
sister's album, he had to purchase a small quantity of this bronze, and
was struck with the great difference between the price of the raw
material and that of the manufactured article. The latter sold for
112_s._ a pound, while the raw material only cost 11_d._ a pound. He
concluded that the difference was caused by the process of manufacture,
and made inquiries with the view of learning the nature of the process.
He found, however, that this manufacture was hardly known in England.
The article was supplied to English dealers from Nuremberg and other
towns in Germany. He did not succeed, therefore, in finding any one who
could tell him how it was produced. In these circumstances he determined
to try to make it himself, and worked for a year and a half at the
solution of this task. Other men had tried it and failed, and he was on
the point of failing too. After eighteen months of fruitless labor he
came to the conclusion that he could not make it, and gave it up. But it
is the highest attribute of genius to succeed where others fail, and,
impelled by this instinct, he resumed his investigations after six
months' repose. At last success crowned his efforts. The profits of his
previous inventions now supplied him with funds sufficient to provide
the mechanical appliances he had designed.
Knowing very little of the patent law, and considering it so insecure
that the safest way to reap the full benefit of his new invention was to
keep it to himself, he determined to work his process of bronze-making
in strict secrecy; and every precaution was therefore adopted for this
purpose. He first put up a small apparatus with his own hands, and
worked it entirely himself. By this means he produced the required
article at 4_s._ a pound. He then sent out a traveller with samples of
it, and the first order he got was at 80_s._ a pound. Being thus fully
assured of success, he communicated his plans to a friend, who agreed to
put £10,000 into the business, as a sleeping partner, in order to work
the new manufacture on a larger scale. The entire working of the concern
was left in the hands of Sir Henry, who accordingly proceeded to enlarge
his means of production. To insure secrecy, he made plans of all the
machinery required, and then divided them into sections. He next sent
these sectional drawings to different engineering works, in order to
get his machinery made piecemeal in different parts of England. This
done, he collected the various pieces, and fitted them up himself,--a
work that occupied him nine months. Finding everything at last in
perfect working order, he engaged four or five assistants in whom he had
confidence, and paid them very high wages on condition that they kept
everything in the strictest secrecy. Bronze powder was now produced in
large quantities by means of five self-acting machines, which not only
superseded hand labor entirely, but were capable of producing as much
daily as sixty skilled operatives could do by the old hand system.
To this day the mechanical means by which his famous gold paint is
produced remains a secret. The machinery is driven by a steam-engine in
an adjoining room; and into the room where the automatic machinery is at
work none but the inventor and his assistants have ever entered. When a
sufficient quantity of work is done, a bell is rung to give notice to
the engine-man to stop the engine; and in this way the machinery has
been in constant use for over forty years without having been either
patented or pirated. Its profit was as great as its success. At first he
made 1,000 per cent profit; and though there are other products that now
compete with this bronze, it still yields 300 per cent profit. "All this
time," says the successful inventor thirty years afterward, "I have been
afraid to improve the machinery, or to introduce other engineers into
the works to improve them. Strange to say, we have thus among us a
manufacture wholly unimproved for thirty years. I do not believe there
is another instance of such a thing in the kingdom. I believe that if I
had patented it, the fourteen years would not have run out without other
people making improvements in the manufacture. Of the five machines I
use, three are applicable to other processes, one to color-making
especially; so much so that notwithstanding the very excellent income
which I derive from the manufacture, I had once nearly made up my mind
to throw it open and make it public, for the purpose of using part of my
invention for the manufacture of colors. Three out of my five assistants
have died; and if the other two were to die and myself too, no one would
know what the invention is." Since this was said (in 1871), Sir Henry
has rewarded the faithfulness of his two surviving assistants by handing
over to them the business and the factory.
BESSEMER STEEL.
Sir Henry Bessemer was first led to turn his attention to the
improvement of the manufacture of iron by a remark of Commander Minie,
who was superintending certain trials of the results of Sir Henry's
experiments in obtaining rotation of shot fired from a smooth-bore gun.
"The shots," said Minie, "rotate properly; but if you cannot get
stronger metal for your guns, such heavy projectiles will be of little
use."
At this time Sir Henry had no connection with the iron or steel trade,
and knew little or nothing of metallurgy. But this fact he has always
represented as being rather an advantage than a drawback. "I find," he
says, "in my experience with regard to inventions, that the most
intelligent manufacturers invent many small improvements in various
departments of their manufactures,--but, generally speaking, these are
only small ameliorations based on the nature of the operation they are
daily pursuing; while, on the contrary, persons wholly unconnected with
any particular business have their minds so free and untrammelled to
new things as they are, and as they would present themselves to an
independent observer, that they are the men who eventually produce the
greatest changes." It was in this spirit that he began his
investigations in metallurgy. His first business was to make himself
acquainted with the information contained in the best works then
published on the subject. He also endeavored to add some practical
knowledge to what he learned from books. With this view he visited the
iron-making districts in the north, and there obtained an insight into
the working merits and defects of the processes then in use. On his
return to London he arranged for the use of an old factory in St.
Pancras, where he began his own series of experiments. He converted the
factory into a small experimental "iron-works," in which his first
object was to improve the quality of iron. For this purpose he made many
costly experiments without the desired measure of success, but not
without making some progress in the right direction. After twelve months
spent in these experiments he produced an improved quality of cast iron,
which was almost as white as steel, and was both tougher and stronger
than the best cast iron then used for ordnance. Of this metal he cast a
small model gun, which was turned and bored. This gun he took to Paris,
and presented it personally to the Emperor,[23] as the result of his
labors thus far. His Majesty encouraged him to continue his experiments,
and desired to be further informed of the results.
As Sir Henry continued his labors, he extended their scope from the
production of refined iron to that of steel; and in order to protect
himself, he took out a patent for each successive improvement. One idea
after another was put to the test of experiment; one furnace after
another was pulled down, and numerous mechanical appliances were
designed and tried in practice. During these experiments he specified a
multitude of improvements in the crucible process of making steel; but
he still felt that much remained to be done. At the end of eighteen
months, he says, "the idea struck me" of rendering cast iron malleable
by the introduction of atmospheric air into the fluid metal. His first
experiment to test this idea was made in a crucible in the laboratory.
He there found that by blowing air into the molten metal in the
crucible, by means of a movable blow-pipe, he could convert ten pounds
or twelve pounds of crude iron into the softest malleable iron. The
samples thus produced were so satisfactory in all their mechanical tests
that he brought them under the notice of Colonel Eardley Wilmot, then
the Superintendent of the Royal Gun Factories, who expressed himself
delighted and astonished at the result, and who offered him facilities
for experimenting in Woolwich Arsenal. These facilities were extended to
him in the laboratory by Professor Abel, who made numberless analyses of
the material as he advanced with his experiments. The testing department
was also put at his disposal, for testing the tensile strength and
elasticity of different samples of soft malleable iron and steel. The
first piece that was rolled at Woolwich was preserved by Sir Henry as a
memento. It was a small bar of metal, about a foot long and an inch
wide, and was converted from a state of pig iron in a crucible of only
ten pounds. That small piece of bar, after being rolled, was tried, to
see how far it was capable of welding; and he was surprised to see how
easily it answered the severest tests. After this he commenced
experiments on a larger scale. He had proved in the laboratory that the
principle of purifying pig iron by atmospheric air was possible; but he
feared, from what he knew of iron metallurgy, that as he approached the
condition of pure soft malleable iron, he must of necessity require a
temperature that he could not hope to attain under these conditions. In
order to produce larger quantities of metal in this way, one of his
first ideas was to apply the air to the molten iron in crucibles; and
accordingly, in October, 1855, he took out a patent embodying this idea.
He proposed to erect a large circular furnace, with openings for the
reception of melting-pots containing fluid iron, and pipes were made to
conduct air into the centre of each pot, and to force it among the
particles of metal. Having thus tested the purifying effect of cold air
introduced into the melting iron in pots, he labored for three months in
trying to overcome the mechanical difficulties experienced in this
complicated arrangement. He wondered whether it would not be possible to
dispense with the pipes and pots, and perform the whole operation in one
large circular or egg-shaped vessel. The difficult thing in doing so,
was to force the air all through the mass of liquid metal. While this
difficulty was revolving in his mind, the labor and anxiety entailed by
previous experiments brought on a short but severe illness; and while he
was lying in bed, pondering for hours upon the prospects of succeeding
in another experiment with the pipes and pots, it occurred to him that
the difficulty might be got over by introducing air into a large vessel
from below into the molten mass within.
Though he entertained grave doubts as to the practicability of carrying
out this idea, chiefly owing to the high temperature required to
maintain the iron in a state of fluidity while the impurities were being
burned out, he determined to put it to a working test; and on recovering
health he immediately began to design apparatus for this purpose. He
constructed a circular vessel, measuring three feet in diameter and five
feet in height, and capable of holding seven hundred-weight of iron. He
next ordered a small, powerful air-engine and a quantity of crude iron
to be put down on the premises in St. Pancras, that he had hired for
carrying on his experiments. The name of these premises was Baxter
House, formerly the residence of old Richard Baxter; and the simple
experiment we are now going to describe has made that house more famous
than ever. The primitive apparatus being ready, the engine was made to
force streams of air, under high pressure, through the bottom of the
vessel, which was lined with fire-clay; and the stoker was told to pour
the metal, when it was sufficiently melted, in at the top of it. A
cast-iron plate--one of those lids which commonly cover the coal-holes
in the pavement--was hung over the converter; and all being got ready,
the stoker in some bewilderment poured in the metal. Instantly out came
a volcanic eruption of such dazzling coruscations as had never been seen
before. The dangling pot-lid dissolved in the gleaming volume of flame,
and the chain by which it hung grew red and then white, as the various
stages of the process were unfolded to the gaze of the wondering
spectators. The air-cock to regulate the blast was beside the
converting-vessel; but no one dared to go near it, much less
deliberately to shut it. In this dilemma, however, they were soon
relieved by finding that the process of decarburization or combustion
had expended all its fury; and, most wonderful of all, the result was
steel! The new metal was tried. Its quality was good. The problem was
solved. The new process appeared successful. The inventor was elated, as
well he might be!
The new process was received with astonishment by all the iron-working
world. It was approved by many, but scoffed at by others. As trials went
on, however, the feeling against it increased. The iron so made was
often "rotten," and no one could tell exactly why.
Bessemer, however, continued to investigate everything for himself,
regardless of all suggestions. Some ideas of permanent value were
offered to him, but were set at nought. It was not till another series
of independent experiments were made that he himself discovered the
secret of failure. It then appeared that, by mere chance, the iron used
in his first experiments was Blaenavon pig, which is exceptionally free
from phosphorus; and consequently, when other sorts of iron were thrown
at random into the converter, the phosphorus manifested its refractory
nature in the unworkable character of the metal produced. Analyses made
by Professor Abel for Sir Henry showed that this was the real cause of
failure. Once convinced of this fact, Sir Henry set to work for the
purpose of removing this hostile element. He saw how phosphorus was
removed in the puddling-furnace, and he now tried to do the same thing
in his converter. Another series of costly and laborious experiments was
conducted; and first one patent and then another was taken out, tried,
and abandoned. His last idea was to make a vessel in which the
converting process did not take place, but into which he could put the
pig iron as soon as it was melted, along with the same kind of materials
that were used in the puddling-furnace. He was then of opinion that he
must come as near to puddling as possible, in order to get the
phosphorus out of the iron. Just as he was preparing to put this plan
into operation, there arrived in England some pig iron which he had
ordered from Sweden some months previously. When this iron, which was
free from phosphorus, was put into the converter, it yielded, in the
very first experiment, a metal of so high a quality that he at once
abandoned his efforts to dephosphorize ordinary iron. The Sheffield
manufacturers were then selling steel at £60 a ton; and he thought that
as he could buy pig iron at £7 a ton, and by blowing it a few minutes in
the converter could make it into what was being sold at such a high
price, the problem was solved.
But there was yet one thing wanting. He had now succeeded in producing
the purest malleable iron ever made, and that, too, by a quicker and
less expensive process than was ever known before. But what he wanted
was to make steel. The former is iron in its greatest possible purity;
the latter is pure iron containing a small percentage of carbon to
harden it. There has been an almost endless controversy in trying to
make a definition that will fix the dividing line that separates the one
metal from the other.[24]