Wednesday, 17 November 2021

Who Invented the Steam Blast - a tract by John Wesley Hackworth 1876

 After the controversy surrounding the publication of Samuel Smiles book The Life of George Stephenson in 1857, John Wesley Hackworth and the descendants of other locomotive pioneers debated and defended their forebears reputation in the press. 

The controversy surround the steam Blast (Blast pipe) invention raised its head again after the jubilee is 1875. John Wesley Hackworth's reply to the Times was not published and he reconfigured it as a tract which he sent out or made available in 1876. The tract is on this site in various relevant places but I've typed it out to make it easier to read - the typeface is very small and to make it easier to copy and paste from for the purpose of quotes. The typed text is below the graphic version..



WHO INVENTED THE STEAM BLAST?

To the Editor of the “Northern Echo”

By John Wesley Hackworth 1876

Sir – In answer to the letters of Miss Gurney and Mr Smiles on the above subject, which appeared in the Times 27th ult. And 1st inst., I beg to say that 16 years before Sir Goldsworthy Gurney professed to have discovered the “steam jet” or “blast,” William Nicolson patented, illustrated, described it in his specification No 2990, and dated 22nd November 1806. This invention he applied to most of the purposes enumerated by Miss Gurney; but it now almost entirely superseded by more economical and modern inventions. While Nicholson’s specifications and Gurney’s pamphlet of 1859 prove that they represent one and the same thing, they are equally conclusive as to the locomotive steam-blast being essentially different. For example, we are informed – “The steam must be high pressure, the steam draught cannot be produced by exhaust steam” Now, as the exhaust steam is the agency employed to produce the locomotive blast - the intermittent sound of which (only emitted when the engine is in motion) is familiar to the ear of everyone, where as the steam jet or ‘blower’ has a continuous sound, caused by steam issuing direct from a boiler when at rest, as well as when in motion – it follows that they are unquestionably two distinct things. It is equally certain that Miss Gurney is in error in her supposition that “Timothy Hackworth conveyed her father’s plan to the north of England” as will be clearly seen in the following facts, which will likewise correct Mr Smiles’s statements. George Stephenson, in his first locomotive at Killingworth in 1814, adopted Blenkinsop’s exhaust, ejecting the steam vertically into the air from an inverted T pipe ; and in his subsequent engines, Stephenson resorted to the plan used by Timothy Hackworth in the Wylam locomotives four or five years before, the method being to carry the exhaust pipes just within the circumference of the chimney, and allow the steam to escape upwards. This became the established mode and the engines did tolerably well in conveying coals at three to five miles an hour on short lines of four and five miles, when due attention was paid to having plentiful supply of steam and water in the boiler with which to commence the journey ; but even with strict observance of these conditions, the engines not infrequently came to a halt and had so to remain till steam was generated to complete the distance. Matters were in this state when the Stockton and Darlington Railway approached completion, and as the distance intended to be worked by horses or locomotives was 20 miles, it was predicted by competent judges that it would be impractical by the latter power, and such it proved to be, for after 18 months’ trial of the locomotives the directors determined to abandon them, as horses were found to do the work at less cost. Letters which I hold from George and Robert Stephenson to my father show their disappointment at this decision. At this juncture Timothy Hackworth proposed to make an engine to answer the purpose. This proposition was considered, and the directors resolved, as a last experiment, that Hackworth should be allowed to carry out his plan. This engine, the “Royal George,” was started in 1827.We can not stop here to enumerate the novelties in its construction ; suffice to say it had his invention “the blast pipe” for the first time, and as used at the present day, only that the contraction is doubled. The result of the working of this engine may be asserted from data adduced from an experiment witnessed by Robert Stephenson, Joseph Lock, my father and myself, which Robert Stephenson had inserted in Rastrick and Walker’s report, which was laid before the directors of the Liverpool and Manchester Railway in March, 1829, to show what a locomotive could accomplish.   

Report p.17 “Hackworth’s engine took 48 ¾ at 112.10 miles an hour, on a level, and the steam was blowing off when the experiment concluded” … “I state the preceding as it has been given to us. Hackworth’s engine is undoubtably the most powerful that has yet been made, as the amount of tons that have been conveyed, compared with the other engines, prove.

In 1828, George Stephenson being wishful to produce an equally powerful engine built the Lancashire Witch, which, besides having the Wylam mode of exhaust, was provided with two bellows – an arrangement he was sanguine would effect the desired result. After the trial – he wrote the following to his friend, Timothy Hackworth –

Liverpool July 25th 1828. We have tried the new locomotive engine at Bolton ; we have also tried the blast to it for burning coke, and I believe it will answer. There are two bellows worked by eccentrics underneath the tender.”

It did not answer, and it is obvious at this date, Stephenson knew nothing of the blast pipe, nor did he acquire a knowledge of it October 1829.At a preliminary trial of the Sanspareil, Hackworth gave Stephenson a brisk run on his engine, when the latter made his observations, and at length put the question – “Timothy, what makes the sparks fly out of the chimney?” Mr Hackworth touched the exhaust pipe near the cylinders and said – “It is the end of this little fellow that does the business”

That night men were sent to purloin Hackworth’s invention, and the Rocket was fitted with a similar blast pipe for the race. I think it unfair on the part of Nicholas Wood to have chronicled (p. 290 e., 1831) the fuel destroyed by a disorganised engine working with an internally burst cylinder. However, after the engine was fitted with a new cylinder, Wood, (in table V11., p. 387) shows that, taking the difference of speed into account, she had the advantage of fuel in the economy of fuel over her rival “Rocket” 14 miles per hour consumed 2,41lbs per ton per mile.

Moreover, the short history sent by Mr John Hick, M.P., with the old engine, when he presented it to the South Kensington Museum, shows the Sanspariel to have been a much superior engine to the Rocket. William Gowland, an engine driver whom George Stephenson brought from Killingworth to assist in opening the Stockton and Darlington line in 1825, after having run the Royal George two years, and been the driver of the Sanspariel at Rainhill, gives testimony in a letter to The Engineer, 23rd October, 1857, to the following effect :-

I was driver of the Royal George on the Stockton and Darlington Railway for about two years, it having come out of Shildon works in 1827 - the complete production of Timothy Hackworth. It contained the blast pipe as perfect as any used at the present day…I can solemnly assure you that when the Sanspariel left Shildon it contained the blast pipe not only by accident but by clear design, with a full knowledge of its value, as proved in the case of the Royal George. Of course everybody knew that the Rocket had not the blast pipe when it came to Rainhill. The Sanspariel had.”

Respecting Nicholas Wood (in treatise 1825), noting the slightly increased draught obtained from his colleague, George Stephenson, turning the exhaust steam into the chimney at Killingworth, this was merely recording an old face known at Wylam years before, which Wood and Stephenson were familiar with, though they differed in opinion as to the utility of adopting it, the effect being so slight. The same phenomenon was observed in Trevithick’s engine, and, although noted in Nicholson’s journal, in 1806, there is no mention made of using the exhaust steam to produce a blast in Trevithick’s minutely drawn patent specification (No. 2,599), the omission proving beyond question that he neither knew its value nor apprehended its principal. In further proof, he patented (Fanners, &c., for creating an artificial draft in the chimney,)

The error in the Encyclopaedia Britannica has been corrected in subsequent editions. Referring to the quotations given by Mr Smiles, first, that –

“During the construction of the Rocket a series of experiments was made with blast pipes of different diameters, and their efficiency was tested by the amount of vacuum that was found in the smoke-box.”

Secondly –

The contraction of the orifice in many of our best locomotives is totally unnecessary, and rather disadvantageous, than otherwise, for since the speed of the engines have been increased the velocity of the steam is quite sufficient to produce the needful rarefaction in the chimney without any contraction whatever.”

In the first place, the smokebox had not then been introduced. The Rocket had not one, she merely had a chimney with a right-angle bend to fix to the boiler end, into which the copper tubes were inserted. And secondly, the early engine exhausts at the cylinder faces and blast orifices were in proportion of three or three and half to one. The present practice is six or seven to one. Hence the contraction is doubled. Imagine an engine constructed with the modern blast orifice - say 16 square inches – carried down uniformly to the cylinder faces - that is eight inches to each, we need no philosopher to tell us that such an engine could not run ; yet this is just what the world is asked to believe. It seems incredible that Robert Stephenson should d have so committed himself, but if on the authority of Mr Smiles we receive these statements they are almost as damaging to Stephenson’s reputation as the Suez canal affair. Instead of Robert Stephenson making such detrimental assertions, would it not have been wiser to have honourably accepted my challenge (in the Engineer, August 14th, 1857) and settled this question on evidence before a properly constituted tribunal?

I am, &c., John Wesley Hackworth

January 12th 1876

…………………………………………………………………………………

This letter is published separately, owing to having been excluded from the Times. A copy can be had on application to John W. Hackworth, Darlington, enclosing postage stamp.

Darlington: Bell, Priestgate.


No comments:

Post a Comment