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Page 22
Boilers also have to be attended to--these were at first rude and now
would be useless. They were unprovided with valves, gauge-cocks, or any
other safety, all of which are now so well understood that nothing but
carelessness can cause a blow-up. One of the greatest causes of danger
is that of letting there be too little water in the boiler, and thus
allowing it to get red-hot, when, if you let in water, such a volume of
steam is generated that no valve will let it escape fast enough. Force
or feed pumps are also required to keep the water in the boiler at a
proper height, which is ascertained by the gauge-cocks. Mercury gauges
for low pressure act according to the pressure of the atmosphere;
high-pressure boilers of course require a different construction, as the
steam is greater in pressure than the air.
Having got so far in my subject, I think before concluding I must devote
a short time in showing the first steps of the locomotive; the more so,
as I am speaking to those who are so largely engaged in the daily
working of that now beautifully perfect machine. Various and for a time
unsuccessful experiments were made to bring out a machinery or
travelling engine, as it was first called. A patent was taken by a Mr.
Trevethick for a locomotive to run on common roads, and to a certain
extent it did work. An amusing anecdote is told of it. In coming up to a
toll-gate, the gatekeeper, almost frightened out of his seven senses,
opened the gate wide for the monster, as he thought, and on being asked
what was to pay, said "Na-na-na-na!" "What have we got to pay?" was
again asked. "No-noth-nothing to pay, my dear Mr. Devil; do drive on as
fast as you can!" This, one of the first steam carriages, reached London
in safety, and was exhibited in the square where the large station of
the London and North-Western Railway now stands. Sir Humphrey Davy took
great interest in it, and, in writing to a friend, said: "I shall hope
soon to see English roads the haunts of Captain Trevethick's dragons."
The badness of roads, however, prevented its coming into general use.
Trevethick in 1804 constructed a locomotive for the Merthyr and Tydvil
Rail in South Wales, which succeeded in drawing ten tons at five miles
an hour. The boiler was of cast-iron, with a one-cylinder engine, spur
gear and a fly-wheel on one side. He sent the waste steam into the
chimney, and by this means was very nearly arriving at the blast-pipe,
afterwards the great and important discovery of George Stephenson. The
jumping motion on the bad roads, however, caused it constantly to be
dismounted, and it was given up as a practical failure, being sent to
work a large pump at a mine. Trevethick was satisfied with a few
experiments, and then gave it up for what he thought more profitable
speculations, and no further advances were made in locomotives for some
years. An imaginary difficulty seems to have been among the obstacles to
its progress. This was the supposition that if a heavy weight were to be
drawn, the grip or bite of the wheels would not be sufficient, but that
they would turn round and leave the engines stationary, hence Trevethick
made his wheels with cogs, which of course tended to cause great jolts,
as well as being destructive to the cast-iron rails.
A Mr. Blenkinsop of Leeds patented in 1811 a locomotive with a racked or
toothed rail. It was supported on four wheels, but they did not drive
the engine; its two cylinders were connected to one wheel behind, which
was toothed and worked in the cog-rail, and so drove the engine. It
began running on Middleton Coal Rail to Leeds, three and a quarter
miles, on the 12th August 1812, and continued a great curiosity to
strangers for some years. In 1816 the Grand Duke Nicholas of Russia saw
this engine working with great interest and expressions of no slight
admiration. An engine then took thirty coal-waggons at three and a
quarter miles in an hour.
We next come to Messrs. Chapman of Newcastle, who in 1812 tried to
overcome the supposed want of adhesion by a chain fixed at the ends of
the line and wound round a grooved drum driven by the engine. It was
tried on the Heaton Rail near Newcastle, but was found to be so clumsy
that it was soon abandoned. The next was a remarkable contrivance--a
mechanical traveller to go on legs. It never got beyond its experimental
state, and unfortunately blew up, killing several people. All these
plans show how lively an interest was then being taken in endeavouring
to bring out a good working locomotive. Mr. Blackett, however,
persevered hard to perfect a railway system, and to work it by
locomotives. The Wylam waggon-way, one of the oldest in the North, was
made of wooden rails down to 1807, and went to the shipping-place for
coals on the Tyne. Each chaldron-waggon was originally drawn by a horse
with a man in charge, only making two journeys in the one day and three
on the following, the man being allowed sevenpence for each journey.
This primitive railway passed before the cottage where George Stephenson
was born, and was consequently one of the first sights his infant eyes
beheld; and little did his parents think what their child was destined
to work out in his day for the advancement of railways. Mr. Blackett
took up the wood and laid an iron plate-way in 1808, and in 1812 he
ordered an engine on Trevetbick's principle. It was a very awkward one,
had only one cylinder of six inches diameter, with a fly-wheel; the
boiler was cast-iron, and was described by the man who had charge of it
as having lots of pumps, cog-wheels, and plugs. It was placed on a
wooden frame with four wheels, and had a barrel of water on another
carriage to serve as a tender. It was at last got on the road, but
would not move an inch, and her driver says:--"She flew all to pieces,
and it was the biggest wonder we were not all blown up." Mr. Blackett
persevered, and had another engine, which did its work much better,
though it often broke down, till at length the workmen declared it a
perfect plague. A good story is told of this engine by a traveller, who,
not knowing of its existence, said, after an encounter with the
Newcastle monster working its great piston, like a huge arm, up and
down, and throwing out smoke and fire, that he had just "encountered a
terrible deevil on the Hight Street road."
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