men of invention and industry-第15章
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schemed a number of its forms and applications; which have been
the subject of many subsequent patents。 It has been so with many
inventions。 It is not the man who gives the first idea of a
machine who is entitled to the merit of its introduction; or the
man who repeats the idea; and re…repeats it; but the man who is
so deeply impressed with the importance of the discovery; that he
insists upon its adoption; will take no denial; and at the risk
of fame and fortune; pushes through all opposition; and is
determined that what he thinks he has discovered shall not perish
for want of a fair trial。 And that this was the case with the
practical introducer of the screw propeller will be obvious from
the following statement。
Francis Pettit Smith was born at Hythe; in the county of Kent; in
1808。 His father was postmaster of the town; and a person of
much zeal and integrity。 The boy was sent to school at Ashford;
and there received a fair amount of education; under the Rev。
Alexander Power。 Young Smith displayed no special characteristic
except a passion for constructing models of boats。 When he
reached manhood; he adopted the business of a grazing farmer on
Romney Marsh。 He afterwards removed to Hendon; north of London;
where he had plenty of water on which to try his model boats。
The reservoir of the Old Welsh Harp was close at handa place
famous for its water…birds and wild fowl。
Smith made many models of boats; his experiments extending over
many years。 In 1834; he constructed a boat propelled by a wooden
screw driven by a spring; the performance of which was thought
extraordinary。 Where he had got his original idea is not known。
It was floating about in many minds; and was no special secret。
Smith; however; arrived at the conclusion that his method of
propelling steam vessels by means of a screw was much superior to
paddlesat that time exclusively employed。 In the following
year; 1835; he constructed a superior model; with which he
performed a number of experiments at Hendon。 In May 1836; he
took out a patent for propelling vessels by means of a screw
revolving beneath the water at the stern。 He then openly
exhibited his invention at the Adelaide Gallery in London。 Sir
John Barrow; Secretary to the Admiralty; inspected the model; and
was much impressed by its action。 During the time it was
publicly exhibited; an offer was made to purchase the invention
for the Pacha of Egypt; but the offer was declined。
At this stage of his operations; Smith was joined by Mr。 Wright;
banker; and Mr。 C。 A。 Caldwell; who had the penetration to
perceive that the invention was one of much promise; and were
desirous of helping its introduction to general use。 They
furnished Smith with the means of constructing a more complete
model。 In the autumn of 1836; a small steam vessel of 10 tons
burthen and six horse…power was built; further to test the
advantages of the invention。 This boat was fitted with a wooden
screw of two whole turns。 On the 1st of November the vessel was
exhibited to the public on the Paddington Canal; as well as on
the Thames; where she continued to ply until the month of
September 1837。
During the trips upon the Thames; a happy accident occurred;
which first suggested the advantage of reducing the length of the
screw。 The propeller having struck upon some obstacle in the
water; about one…half of the length of the screw was broken off;
and it was found that; the vessel immediately shot ahead and
attained a much greater speed than before。 In consequence of
this discovery; a new screw of a single turn was fitted to her;
after which she was found to work much better。
Having satisfied himself as to the eligibility of the propeller
in smooth water; Mr。 Smith then resolved to take his little
vessel to the open sea; and breast the winds and the waves。
Accordingly; one Saturday in the month of September 1837; he
proceeded in his miniature boat; down the river; from Blackwall
to Gravesend。 There he took a pilot on board; and went on to
Ramsgate。 He passed through the Downs; and reached Dover in
safety。 A trial of the vessel's performance was made there in
the presence of Mr。 Wright; the banker; and Mr。 Peake; the civil
engineer。 From Dover the vessel went on to Folkestone and Hythe;
encountering severe weather。 Nevertheless; the boat behaved
admirably; and attained a speed of over seven miles an hour。
Though the weather had become stormy and boisterous; the little
vessel nevertheless set out on her return voyage to London。
Crowds of people assembled to witness her departure; and many
nautical men watched her progress with solicitude as she steamed
through the waves under the steep cliffs of the South Foreland。
The courage of the undertaking; and the unexpected good
performance of the little vessel; rendered her an object of great
interest and excitement as she 〃screwed〃 her way along the coast。
The tiny vessel reached her destination in safety。 Surely the
difficulty of a testing trial; although with a model screw; had
at length been overcome。 But no! The paddle still possessed the
ascendency; and a thousand interestsinvested capital; use and
wont; and conservative instinctsall stood in the way。
Some years beforeindeed; about the time that Smith took out his
patentCaptain Ericsson; the Swede; invented a screw propeller。
Smith took out his patent in May; 1836; and Ericsson in the
following July。 Ericsson was a born inventor。 While a boy in
Sweden; he made saw mills and pumping engines; with tools
invented by himself。 He learnt to draw; and his mechanical
career began。 When only twelve years old; he was appointed a
cadet in the Swedish corps of mechanical engineers; and in the
following year he was put in charge of a section of the Gotha
Ship Canal; then under construction。 Arrived at manhood;
Ericsson went over to England; the great centre of mechanical
industry。 He was then twenty…three years old。 He entered into
partnership with John Braithwaite; and with him constructed the
Novelty; which took part in the locomotive competition at
Rainhill on the 6th October; 1829。 The prize was awarded to
Stephenson's Rocket on the 14th; but it was acknowledged by The
Times of the day that the Novelty was Stephenson's sharpest
competitor。
Ericsson had a wonderfully inventive brain; a determined purpose;
and a great capacity for work。 When a want was felt; he was
immediately ready with an invention。 The records of the Patent
Office show his incessant activity。 He invented pumping engines;
steam engines; fire engines; and caloric engines。 His first
patent for a 〃reciprocating propeller〃 was taken out in October
1834。 To exhibit its action; he had a small boat constructed of
only about two feet long。 It was propelled by means of a screw;
and was shown at work in a circular bath in London。 It performed
its voyage round the basin at the rate of about three miles an
hour。 His patent for a 〃spiral propeller;〃 was taken out in July
1836。 This was the invention; to exhibit which he had a vessel
constructed; of about 40 feet long; with two propellers; each of
5 feet 3 inches diameter。
This boat; the Francis B。 Ogden; proved extremely successful。
She moved at a speed of about ten miles an hour。 She was able to
tow vessels of 140 tons burthen at the rate of seven miles an
hour。 Perceiving the peculiar and admirable fitness of the
screw…propeller for ships of war; Ericsson invited the Lords of
the Admiralty to take an excursion in tow of his experimental
boat。 〃My Lords〃 consented; and the Admiralty barge contained on
this occasion; Sir Charles Adam; senior Lord; Sir William
Symonds; surveyor; Sir Edward Parry; of Polar fame; Captain
Beaufort; hydrographer; and other men of celebrity。 This
distinguished company embarked at Somerset House; and the little
steamer; with her precious charge; proceeded down the