men of invention and industry-第16节
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of saving the Athenian people。
'4' An account of these is given by Bennet Woodcraft in his
Sketch of the Origin and Progress of Steam Navigation; London;
1848。
'5' See Industrial Biography; pp。 183…197;
'6' The story is told in Scribner's Monthly Illustrated Magazine;
for April 1879。 Ericsson's modest bill was only 15;000 for two
years' labour。 He was put off from year to year; and at length
the Government refused to pay the amount。 〃The American
Government;〃 says the editor of Scribner; 〃will not appropriate
the money to pay it; and that is all。 It is said to be the
nature of republics to be ungrateful; but must they also be
dishonest?〃
'7' Memoirs of the Life and Services of Rear…Admiral Sir William
Symonds; Kt。; p。 332。
CHAPTER III。'1'
JOHN HARRISON: INVENTOR OF THE MARINE CHRONOMETER。
No man knows who invented the mariner's compass; or who first
hollowed out a canoe from a log。 The power to observe accurately
the sun; moon; and planets; so as to fix a vessel's actual
position when far out of sight of land; enabling long voyages to
be safely made; the marvellous improvements in ship…building;
which shortened passages by sailing vessels; and vastly reduced
freights even before steam gave an independent force to the
carriereach and all were done by small advances; which together
contributed to the general movement of mankind。。。。 Each owes all
to the others。 The forgotten inventors live for ever in the
usefulness of the work they have done and the progress they have
striven for。〃H。 M。 Hyndman。
One of the most extraordinary things connected with Applied
Science is the method by which the Navigator is enabled to find
the exact spot of sea on which his ship rides。 There may be
nothing but water and sky within his view; he may be in the midst
of the ocean; or gradually nearing the land; the curvature of the
globe baffles the search of his telescope; but if he have a
correct chronometer; and can make an astronomical observation; he
may readily ascertain his longitude; and know his approximate
positionhow far he is from home; as well as from his intended
destination。 He is even enabled; at some special place; to send
down his grappling…irons into the sea; and pick up an electrical
cable for examination and repair。
This is the result of a knowledge of Practical Astronomy。 〃Place
an astronomer;〃 says Mr。 Newcomb; 〃on board a ship; blindfold
him; carry him by any route to any ocean on the globe; whether
under the tropics or in one of the frigid zones; land him on the
wildest rock that can be found; remove his bandage; and give him
a chronometer regulated to Greenwich or Washington time; a
transit instrument with the proper appliances; and the necessary
books and tables; and in a single clear night he can tell his
position within a hundred yards by observations of the stars。
This; from a utilitarian point of view; is one of the most
important operations of Practical Astronomy。〃'2'
The Marine Chronometer was the outcome of the crying want of the
sixteenth century for an instrument that should assist the
navigator to find his longitude on the pathless ocean。 Spain was
then the principal naval power; she was the most potent monarchy
in Europe; and held half America under her sway。 Philip III。
offered 100;000 crowns for any discovery by means of which the
longitude might be determined by a better method than by the log;
which was found very defective。 Holland next became a great
naval power; and followed the example of Spain in offering 30;000
florins for a similar discovery。 But though some efforts were
made; nothing practical was done; principally through the
defective state of astronomical instruments。 England succeeded
Spain and Holland as a naval power; and when Charles II。
established the Greenwich Observatory; it was made a special
point that Flamsteed; the Astronomer…Royal; should direct his
best energies to the perfecting of a method for finding the
longitude by astronomical observations。 But though Flamsteed;
together with Halley and Newton; made some progress; they were
prevented from obtaining ultimate success by the want of
efficient chronometers and the defective nature of astronomical
instruments。
Nothing was done until the reign of Queen Anne; when a petition
was presented to the Legislature on the 25th of May; 1714; by
〃several captains of Her Majesty's ships; merchants in London;
and commanders of merchantmen; in behalf of themselves; and of
all others concerned in the navigation of Great Britain;〃 setting
forth the importance of the accurate discovery of the longitude;
and the inconvenience and danger to which ships were subjected
from the want of some suitable method of discovering it。 The
petition was referred to a committee; which took evidence on the
subject。 It appears that Sir Isaac Newton; with his
extraordinary sagacity; hit the mark in his report。 〃One is;〃 he
said; 〃by a watch to keep time exactly; but; by reason of the
motion of a ship; and the variation of heat and cold; wet and
dry; and the difference of gravity in different latitudes; such a
watch hath not yet been made。〃
An Act was however passed in the Session of 1714; offering a very
large public reward to inventors: 10;000L。 to any one who should
discover a method of determining the longitude to one degree of a
great circle; or 60 geographical miles; 15;000L。 if it determined
the same to two…thirds of that distance; or 40 geographical
miles; and 20;000L。 if it determined the same to one…half of the
same distance; or 30 geographical miles。 Commissioners were
appointed by the same Act; who were instructed that 〃one moiety
or half part of such reward shall be due and paid when the said
commissioners; or the major part of them; do agree that any such
method extends to the security of ships within 80 geographical
miles of the shore; which are places of the greatest danger; and
the other moiety or half part when a ship; by the appointment of
the said commissioners; or the major part of them; shall actually
sail over the ocean; from Great Britain to any such port in the
West Indies as those commissioners; or the major part of them;
shall choose or nominate for the experiment; without losing the
longitude beyond the limits before mentioned。〃
The terms of this offer indicate how great must have been the
risk and inconvenience which it was desired to remedy。 Indeed;
it is almost inconceivable that a reward so great could be held
out for a method which would merely afford security within eighty
geographical miles!
This splendid reward for a method of discovering the longitude
was offered to the worldto inventors and scientific men of all
countries without restriction of race; or nation; or language。
As might naturally be expected; the prospect of obtaining it
stimulated many ingenious men to make suggestions and contrive
experiments; but for many years the successful construction of a
marine time…keeper seemed almost hopeless。 At length; to the
surprise of every one; the prize was won by a village
carpentera person of no school; or university; or college
whatever。
Even so distinguished an artist and philosopher as Sir
Christopher Wren was engaged; as late in his life as the year
1720; in attempting to solve this important problem。 As has been
observed; in the memoir of him contained in the 'Biographia
Britannica;''3' 〃This noble invention; like some others of the
most useful ones to human life; seems to be reserved for the
peculiar glory of an ordinary mechanic; who; by indefatigable
industry; under the guidance of no ordinary sagacity; hath
seemingly at last surmounted all difficulties; and brought it to
a most unexpected degree of perfection。〃 Where learning and
science failed; natural genius seems to have triumphed。
The truth is; that the great mechanic; like the great poet; is
born; not made; and John Harrison; the winner of the famous
prize; was a born mechanic。 He did not; however; accomplish his
object without the exercise of the greatest skill; patience; and
perseverance。 His efforts were long; laborious; and sometimes
apparently hopeless。 Indeed; his life; so far as we can
ascertain the facts; affords one of the finest examples of
difficulties encountered and triumphantly overcome; and of
undaunted perseverance eventually crowned by success; which is to
be found in the whole range of biography。
No complete narrative of Harrison's career was ever written。
Only a short notice of him appears in the 'Biographia
Britannica;' published in 1766; during his lifetime'the facts
of which were obtained from himself。 A few notices of him appear
in the 'Annual Register;' also published during his lifetime。
The final notice appeared in the volume published in 1777; the
year after his death。 No Life of him has since appeared。 Had he
been