others to work out the problem of the
locomotive engine.
Murdock's model remained but a curious toy, which he took
pleasure in exhibiting to his
intimate friends; and, though he
long continued to
speculate about road locomotion, and was
persuaded of its practicability, he abstained from embodying his
ideas of the necessary engine in any complete
working form.
Murdock
nevertheless continued
inventing, for the man who is
given to
invent, and who possesses the gift of
insight, cannot
rest. He lived in the midst of
inventors. Watt and Boulton were
constantly suggesting new things, and Murdock became possessed by
the same spirit. In 1791 he took out his first
patent. It was
for a method of preserving ships' bottoms from foulness by the
use of a certain kind of
chemical paint. Mr. Murdock's grandson
informs us that it was recently re-
patented and was the cause of
a lawsuit, and that Hislop's
patent for revivifying gas-lime
would have been an infringement, if it had not expired.
Murdock is still better known by his
invention of gas for
lighting purposes. Several independent inquirers into the
constituents of Newcastle coal had arrived at the
conclusion that
nearly one-third of the substance was
driven off in vapour by the
application of heat, and that the vapour so
driven off was
inflammable. But no
suggestion had been made to apply this
vapour for
lighting purposes until Murdock took the matter in
hand. Mr. M. S. Pearse has sent us the following interesting
reminiscence: "Some time since, when in the West of Cornwall, I
was
anxious to find out whether any one remembered Murdock. I
discovered one of the most
respectable and
intelligent men in
Camborne, Mr. William Symons, who not only
distinctly remembered
Murdock, but had
actually been present on one of the first
occasions when gas was used. Murdock, he says, was very fond of
children, and not unfrequently took them into his
workshop to
show them what he was doing. Hence it happened that on one
occasion this gentleman, then a boy of seven or eight, was
standing outside Murdock's door with some other boys,
trying to
catch sight of some special
mystery inside, for Dr. Boaze, the
chief doctor of the place, and Murdock had been busy all the
afternoon. Murdock came out, and asked my informant to run down
to a shop near by for a
thimble. On returning with the
thimble,
the boy pretended to have lost it, and,
whilst searching in every
pocket, he managed to slip inside the door of the
workshop, and
then produced the
thimble. He found Dr. Boaze and Murdock with a
kettle filled with coal. The gas issuing from it had been burnt
in a large metal case, such as was used for blasting purposes.
Now, however, they had
applied a much smaller tube, and at the
end of it fastened the
thimble, through the small perforations
made in which they burned a
continuous jet for some time."[7]
After numerous experiments, Murdock had his house in Cross Street
fitted up in 1792 for being lit by gas. The coal was subjected
to heat in an iron
retort, and the gas was conveyed in pipes to
the offices and the different rooms of the house, where it was
burned at proper apertures or
burners.[8] Portions of the gas
were also confined in
portablevessels of tinned iron, from which
it was burned when required, thus forming a
moveable gas-light.
Murdock had a gas
lantern in regular use, for the purpose of
lighting himself home at night across the moors, from the mines
where he was
working, to his home at Redruth. This
lantern was
formed by filling a bladder with gas and fixing a jet to the
mouthpiece at the bottom of a glass
lantern, with the bladder
hanging underneath.
Having satisfied himself as to the superior
economy of coal gas,
as compared with oils and
tallow, for the purposes of
artificialillumination, Murdock mentioned the subject to Mr. James Watt,
jun., during a brief visit to Soho in 1794, and urged the
propriety of
taking out a
patent. Watt was, however, indifferent
to
taking out any further
patents, being still engaged in
contesting with the Cornish mine-owners his father's rights to
the user of the condensing
steam-engine. Nothing
definite was
done at the time. Murdock returned to Cornwall and continued his
experiments. At the end of the same year he exhibited to Mr.
Phillips and others, at the Polgooth mine, his
apparatus for
extracting gases from coal and other substances, showed it in
use, lit the gas which issued from the
burner, and showed its
"strong and beautiful light." He afterwards exhibited the same
apparatus to Tregelles and others at the Neath Abbey Company's
ironworks in Glamorganshire.
Murdock returned to Soho in 1798, to take up his permanent
residence in the neighbourhood. When the mine owners heard of
his
intention to leave Cornwall, they combined in
offering him a
handsome salary provided he would remain in the county; but his
attachment to his friends at Soho would not allow him to comply
with their request. He again urged the firm of Boulton and Watt
to take out a
patent for the use of gas for
lighting purposes.
But being still embroiled in their
tedious and
costly lawsuit,
they were naturally
averse to risk
connection with any other
patent. Watt the younger, with whom Murdock communicated on the
subject, was aware that the current of gas obtained from the
distillation of coal in Lord Dundonald's tar-ovens had been
occasionally set fire to, and also that Bishop Watson and others
had burned gas from coal, after conducting it through tubes, or
after it had issued from the
retort. Mr. Watt was, however,
quite satisfied that Murdock was the first person who had
suggested its
economicalapplication for public and private uses.
But he was not clear, after the legal difficulties which had been
raised as to his father's
patent rights, that it would be safe to
risk a further
patent for gas.
Mr. Murdock's
suggestion,
accordingly, was not acted upon. But
he went on
inventing in other directions. He thenceforward
devoted himself entirely to
mechanical pursuits. Mr. Buckle has
said of him:-- "The rising sun often found him, after a night
spent in
incessant labour, still at the anvil or turning-lathe;
for with his own hands he would make such articles as he would
not
intrust to unskilful ones." In 1799 he took out a
patent(No. 2340), embodying some very important
inventions. First, it
included the endless screw
working into a toothed-wheel, for
boring steam-
cylinders, which is still in use. Second, the
casting of a steam-jacket in one
cylinder, instead of being made
in separate segments bolted together with caulked joints, as was
previously done. Third, the new double-D slide-valve, by which
the
construction and
working of the
steam-engine was simplified,
and the loss of steam saved, as well as the cylindrical valve for
the same purpose. And fourth, improved
rotary engines. One of
the latter was set to drive the machines in his private
workshop,
and continued in nearly
constant work and in perfect use for
about thirty years.
In 1801, Murdock sent his two sons William and John to the Ayr
Academy, for the benefit of Scotch education. In the summer-time
they spent their
vacation at Bellow Mill, which their grandfather
still continued to occupy. They fished in the river, and "caught
a good many trout." The boys corresponded
regularly with their
father at Birmingham. In 1804, they seem to have been in a state
of great
excitement about the expected
landing of the French in
Scotland. The volunteers of Ayr
amounted to 300 men, the cavalry
to 150, and the riflemen to 50. "The riflemen," says John, "go
to the
seashore every Saturday to shoot at a target. They stand
at 70 paces distant, and out of 100 shots they often put in 60
bullets!" William says, "Great preparations are still making for
the
reception of the French. Several thousand of pikes are
carried through the town every week; and all the volunteers and
riflemen have received orders to march at a moment's warning."
The alarm, however, passed away. At the end of 1804, the two
boys received prizes; William got one in
arithmetic and another
in the Rector's
composition class; and John also obtained two,
one in the
mathematical class, and the other in French.
To return to the
application of gas for
lighting purposes. In
1801, a plan was proposed by a M. Le Blond for
lighting a part of