an autobiography-第75节
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This state of the iron is indicated by a general loss of fluidity； accompanied by a tendency to gather together in globular masses。 The puddler； by his dexterous use of the end of the rabbling bar； puts the masses together； and； in fact； welds the new…born particles of malleable iron into puddle…balls of about three…quarters of a hundredweight each。 These are successively removed from the pool of the puddling furnace； and subjected to the energetic blows of the steam hammer； which drives out all the scoriae lurking within the spongy puddle…balls； and thus welds them into compact masses of malleable iron。 When reheated to a welding heat； they are rolled out into flat bars or round rods； in a variety of sizes； so as to be suitable for the consumer。
The manual and physical labour of the puddler is tedious； fatiguing； and unhealthy。 The process of puddling occupies about an hour's violent labour； and only robust young men can stand the fatigue and violent heat。 I had frequent opportunities of observing the labour and unhealthiness of the process； as well as the great loss of time required to bring it to a conclusion。 It occurred to me that much of this could be avoided by employing some other means for getting rid of the superfluous carbon； and bringing the molten cast…iron into a malleable condition。
The method that occurred to me was the substitution of a small steam pipe in the place of the puddler's rabbling bar。 By having the end of this steam pipe bent downwards so as to reach the bottom of the pool； and then to discharge a current of steam beneath the surface of the molten cast iron； I thought that I should by this simple means supply a most effective carbon…oxidating agent； at the same time that I produced a powerful agitating action within the pool。 Thus the steam would be decomposed and supply oxygen to the carbon of the cast…iron； while the mechanical action of the rush of steam upwards would cause so violent a commotion throughout the pool of melted iron as to exceed the utmost efforts of the labour of the puddler。 All the gases would pass up the chimney of the puddling furnace； and the puddler would not be subject to their influence。 Such was the method specified in my patent of l854* ＇footnote。。。 Specification of James NasmythEmployment of steam in the process of puddling iron。 May 4； 1854； No。 1001。 。。。＇
My friend； Thomas Lever Rushton； proprietor of the Bolton Ironworks； was so much impressed with the soundness of the principle； as well as with the great simplicity of carrying the invention into practical effect； that he urged me to secure the patent； and he soon after gave me the opportunity of trying the process at his works。 The results were most encouraging。 There was a great saving of labour and time compared with the old puddling process； and the malleable iron produced was found to be of the highest order as regarded strength； toughness； and purity。 My process was soon after adopted by several iron manufacturers with equally favourable results。 Such； however； was the energy of the steam； that unless the workmen were most careful to regulate its force and the duration of its action； the waste of iron by undue oxidation was such as in a great measure to neutralise its commercial gain as regarded the superior value of the malleable iron thus produced。
Before I had time or opportunity to remove this commercial difficulty； Mr。 Bessemer had secured his patent of the l7th of October； 1855。 By this patent he employed a blast of air to do the same work as I had proposed to accomplish by means of a blast of steam； forced up beneath the surface of the molten cast iron。 He added some other improvements； with that happy fertility of invention which has always characterised him。 The results were so magnificently successful as to totally eclipse my process； and to cast it comparatively into the shade。 At the same time I may say that I was in a measure the pioneer of his invention； that I initiated a new system； and led to one of the most important improvements in the manufacture of iron and steel that has ever been given to the world。
Mr。 Bessemer brought the subject of his invention before the meeting of the British Association at Cheltenham in the autumn of 1856。 There he read his paper 〃On the Manufacture of Iron into Steel without Fuel。〃* ＇footnote。。。 On the morning of the day on which the paper was to be read； Mr。 Bessemer was sitting at breakfast at his hotel； when an ironmaster （to whom he was unknown） said； laughing； to a friend within his hearing； 〃Do you know that there is somebody come down from London to read us a paper on making steel from cast iron without fuel？ Did you ever hear of such nonsense？〃 The title of the paper was perhaps a misnomer； but the correctness of the principles on which the pig iron was converted into malleable iron； as explained by the inventor； was generally recognised； and there seemed every reason to anticipate that the process would before long come into general use。 。。。＇
I was present on the occasion； and listened to his statement with mingled feelings of regret and enthusiasmof regret； because I had been so clearly superseded and excelled in my performances； and of enthusiasmbecause I could not but admire and honour the genius who had given so great an invention to the mechanical world。 I immediately took the opportunity of giving my assent to the principles which he had propounded。 My words were not reported at the time； nor was Mr。 Bessemer's paper printed by the Association； perhaps because it was thought of so little importance but； on applying to Mr。 （now Sir Henry） Bessemer； he was so kind as to give me the following as his recollection of the words which I used on the occasion。
〃I shall ever feel grateful；〃 says Sir Henry； 〃for the noble way in which you spoke at the meeting at Cheltenham of my invention。 If I remember rightly； you held up a piece of my malleable iron； saying words to this effect： 'Here is a true British nugget！ Here is a new process that promises to put an end to all puddling； and I may mention that at this moment there are puddling furnaces in successful operation where my patent hollow steam Rabbler is at work； producing iron of superior quality by the introduction of jets of steam in the puddling process。 I do not； however； lay any claim to this invention of Mr。 Bessemer； but I may fairly be entitled to say that I have advanced along the road on which he has travelled so many miles； and has effected such unexpected results that I do not hesitate to say that I may go home from this meeting and tear up my patent； for my process of puddling is assuredly superseded。'〃
After giving an account of the true origin of his process； in which he had met with failures as well as successes； but at last recognised the decarburation of pig iron by atmospheric air； Sir Henry proceeds to say：
〃I prepared to try another experiment； in a crucible having no hole the the bottom； but which was provided with an iron pipe put through a hole in the cover； and passing down nearly to the bottom of the crucible。 The small lumps and grains of iron were packed around fit； so as nearly to fill the crucible。 A blast of air was to be forced down the pipe so as to rise up among the pieces of granular iron and partially decarburise them。 The pipe could then be withdrawn； and the fire urged until the metal with its coat of oxyde was fused； and cast steel thereby produced。
〃While the blowing apparatus for this experiment was being fitted up； I was taken with one of those short but painful illnesses to which I was subject at that time。 I was confined to my bed； and it was then that my mind； dwelling for hours together on the experiment about to be made； suggested that instead of trying to decarburise the granulated metal by forcing the air down the vertical pipe among the pieces of iron； the air would act much more energetically and more rapidly if I first melted the iron in the crucible； and forced the air down the pipe below the surface of the fluid metal； and thus burn out the carbon and silicum which it contained。
〃This appeared so feasible； and in every way so great an improvement； that the experiment on the granular pieces was at once abandoned； and； as soon as I was well enough； I proceeded to try the experiment of forcing the air under the fluid metal。 The result was marvellous。 Complete decarburation was effected in half an hour。 The heat produced was immense； but； unfortunately more than half the metal was blown out of the pot。 This led to the use of pots with large hollow perforated covers； which effectually prevented the loss of metal。 These experiments continued from January to October 1855。 I have by me on the mantelpiece at this moment； a small piece of rolled bar iron which was rolled at Woolwich arsenal； and exhibited a year later at Cheltenham。
〃I then applied for a patent； but before preparing my provisional specification （dated October 17； 1855）； I searched for other patents to ascertain whether anything of the sort had been done before。 I then found your patent for puddling with the steam rabble； and also Martin's patent for the use of steam in gutters while molten iron was being conveyed from the blast furnace t
