第 71 节
作者:铲除不公      更新:2021-03-08 19:38      字数:9322
  occasion; where the forging required the most powerful blow; it
  received next to no blow at all;the clear space for fall being
  almost entirely occupied by the work on the anvil。
  The obvious remedy was to invent some method; by which a block of
  iron should be lifted to a sufficient height above the object on
  which it was desired to strike a blow; and let the block fall down
  upon the work;guiding it in its descent by such simple means as
  should give the required precision in the percussive action of the
  falling mass。  Following out this idea; Mr。 Nasmyth at once sketched
  on paper his steam…hammer; having it clearly before him in his mind's
  eye a few minutes after receiving Mr。 Humphries' letter narrating his
  unlooked…for difficulty。  The hammer; as thus sketched; consisted of;
  first an anvil on which to rest the work; second; a block of iron
  constituting the hammer or blow…giving part; third; an inverted
  steam…cylinder to whose piston…rod the block was attached。  All that
  was then required to produce by such means a most effective hammer;
  was simply to admit steam in the cylinder so as to act on the under
  side of the piston; and so raise the block attached to the
  piston…rod; and by a simple contrivance to let the steam escape and
  so permit the block rapidly to descend by its own gravity upon the
  work then on the anvil。  Such; in a few words; is the rationale of the
  steam…hammer。
  By the same day's post; Mr。 Nasmyth wrote to Mr。 Humphries; inclosing
  a sketch of the invention by which he proposed to forge the 〃Great
  Britain〃 paddle…shaft。  Mr。 Humphries showed it to Mr。 Brunel; the
  engineer…inchief of the company; to Mr。 Guppy; the managing director;
  and to others interested in the undertaking; by all of whom it was
  heartily approved。  Mr。 Nasmyth gave permission to communicate his
  plans to such forge proprietors as might feel disposed to erect such
  a hammer to execute the proposed work;the only condition which he
  made being; that in the event of his hammer being adopted; he was to
  be allowed to supply it according to his own design。
  The paddle…shaft of the 〃Great Britain〃 was; however; never forged。
  About that time; the substitution of the Screw for the Paddle…wheel
  as a means of propulsion of steam…vessels was attracting much
  attention; and the performances of the 〃Archimedes〃 were so
  successful as to induce Mr。 Brunel to recommend his Directors to
  adopt the new power。  They yielded to his entreaty。  The great engines
  which Mr。 Humphries had designed were accordingly set aside; and he
  was required to produce fresh designs of engines suited for screw
  propulsion。  The result was fatal to Mr。 Humphries。  The labour; the
  anxiety; and perhaps the disappointment; proved too much for him; and
  a brain…fever carried him off; so that neither his great paddle…shaft
  nor Mr。 Nasmyth's steam…hammer to forge it was any longer needed。
  The hammer was left to bide its time。  No forge…master would take it
  up。  The inventor wrote to all the great firms; urging its superiority
  to every other tool for working malleable iron into all kinds of
  forge work。  Thus he wrote and sent illustrative sketches of his
  hammer to Accramans and Morgan of Bristol; to the late Benjamin Hick
  and Rushton and Eckersley of Bolton; to Howard and Ravenhill of
  Rotherhithe; and other firms; but unhappily bad times for the iron
  trade had set in; and although all to whom he communicated his design
  were much struck with its simplicity and obvious advantages; the
  answer usually given was〃We have not orders enough to keep in
  work the forge…hammers we already have; and we do not desire at
  present to add any new ones; however improved。〃  At that time no
  patent had been taken out for the invention。  Mr。 Nasmyth had not yet
  saved money enough to enable him to do so on his own account; and his
  partner declined to spend money upon a tool that no engineer would
  give the firm an order for。  No secret was made of the invention; and;
  excepting to its owner; it did not seem to be worth one farthing。
  Such was the unpromising state of affairs; when M。 Schneider; of the
  Creusot Iron Works in France; called at the Patricroft works together
  with his practical mechanic M。 Bourdon; for the purpose of ordering
  some tools of the firm。  Mr。 Nasmyth was absent on a journey at the
  time; but his partner; Mr。 Gaskell; as an act of courtesy to the
  strangers; took the opportunity of showing them all that was new and
  interesting in regard to mechanism about the works。  And among other
  things; Mr。 Gaskell brought out his partner's sketch or 〃Scheme
  book;〃 which lay in a drawer in the office; and showed them the
  design of the Steam Hammer; which no English firm would adopt。  They
  were much struck with its simplicity and practical utility; and M。
  Bourdon took careful note of its arrangements。  Mr。 Nasmyth on his
  return was informed of the visit of MM。 Schneider and Bourdon; but
  the circumstance of their having inspected the design of his
  steam…hammer seems to have been regarded by his partner as too
  trivial a matter to be repeated to him; and he knew nothing of the
  circumstance until his visit to France in April; 1840。  When passing
  through the works at Creusot with M。 Bourdon; Mr。 Nasmyth saw a crank
  shaft of unusual size; not only forged in the piece; but punched。  He
  immediately asked; 〃How did you forge that shaft?〃  M。 Bourdon's
  answer was; 〃Why; with your hammer; to be sure!〃  Great indeed was
  Nasmyth's surprise; for he had never yet seen the hammer; except in
  his own drawing!  A little explanation soon cleared all up。  M。 Bourdon
  said he had been so much struck with the ingenuity and simplicity of
  the arrangement; that he had no sooner returned than he set to work;
  and had a hammer made in general accordance with the design Mr。
  Gaskell had shown him; and that its performances had answered his
  every expectation。  He then took Mr。 Nasmyth to see the steam…hammer;
  and great was his delight at seeing the child of his brain in full
  and active work。  It was not; according to Mr。 Nasmyth's ideas; quite
  perfect; and he readily suggested several improvements; conformable
  with the original design; which M。 Bourdon forthwith adopted。
  On reaching England; Mr。 Nasmyth at once wrote to his partner telling
  him what he had seen; and urging that the taking out of a patent for
  the protection of the invention ought no longer to be deferred。  But
  trade was still very much depressed; and as the Patricroft firm
  needed all their capital to carry on their business; Mr。 Gaskell
  objected to lock any of it up in engineering novelties。  Seeing
  himself on the brink of losing his property in the invention; Mr。
  Nasmyth applied to his brother…in…law; William Bennett; Esq。; who
  advanced him the requisite money for the purposeabout 280L。;
  and the patent was secured in June 1840。  The first hammer; of 30
  cwt。; was made for the Patricroft works; with the consent of the
  partners; and in the course of a few weeks it was in full work。  The
  precision and beauty of its actionthe perfect ease with which it
  was managed; and the untiring force of its percussive blowswere
  the admiration of all who saw it; and from that moment the
  steam…hammer became a recognised power in modern mechanics。  The
  variety or gradation of its blows was such; that it was found
  practicable to manipulate a hammer of ten tons as easily as if it had
  only been of ten ounces weight。  It was under such complete control
  that while descending with its greatest momentum; it could be
  arrested at any point with even greater ease than any instrument used
  by hand。  While capable of forging an Armstrong hundred…pounder; or
  the sheet…anchor for a ship of the line; it could hammer a nail; or
  crack a nut without bruising the kernel。  When it came into general
  use; the facilities which it afforded for executing all kinds of
  forging had the effect of greatly increasing the quantity of work
  done; at the same time that expense was saved。  The cost of making
  anchors was reduced by at least 50 per cent。; while the quality of
  the forging was improved。  Before its invention the manufacture of a
  shaft of l5 or 20cwt。  required the concentrated exertions of a large
  establishment; and its successful execution was regarded as a great
  triumph of skill。; whereas forgings of 20 and 30 tons weight are now
  things of almost every…day occurrence。  Its advantages were so
  obvious; that its adoption soon became general; and in the course of
  a few years Nasmyth steam…hammers were to be found in every
  well…appointed workshop both at home and abroad。  Many modifications
  have been made in the tool; by Condie; Morrison; Naylor; Rigby; and
  others; but Nasmyth's was the father of them all; and still holds its
  ground。*
  'footnote。。。
  Mr。 Nasmyth has lately introduced; with the assistance of Mr。 Wilson
  of the Low Moor Iron Works; a new; exceedingly ingenious; and very
  simple contrivance for working the hammer。