Robert Mushet





Robert (Forester) Mushet (1811-1891), born in the Forest of Dean,

Gloucestershire, of a Scots father (David, 1772-1847) himself a noted

contributor to the metallurgy of iron and steel, is, like the American

William Kelly, considered by many to have been a victim of Bessemer's

astuteness--or villainy. Because of Robert Mushet's preference for the

quiet of Coleford, many important facts about his career are lacking;

but even if his physical life was that of a recluse, his frequent and

verbose contributions to the correspondence columns of the technical

press made him well-known to the iron trade. It is from these letters

that he must be judged.



In view of his propensity to intervene pontifically in every discussion

concerning the manufacture of iron and steel, it is somewhat surprising

that he refrained from comment on Bessemer's British Association

address of August 1856 for more than fourteen months. The debate was

opened over the signature of his brother David who shared the family

facility with the pen.[22] Recognizing Bessemer's invention as a

"congruous appendage to [the] now highly developed powers of the blast

furnace" which he describes as "too convenient, too powerful and too

capable of further development to be superseded by any retrograde

process," David Mushet greeted Bessemer's discovery as "one of the

greatest operations ever devised in metallurgy."[23] A month later,

however, David Mushet had so modified his opinion of Bessemer as to

come to the conclusion that the latter "must indeed be classed with the

most unfortunate inventors." He gave as his reason for this turnabout

his discovery that Joseph Martien had demonstrated his process of

"purifying" metal successfully and had indeed been granted a

provisional patent a month before Bessemer. The sharp practice of

Martien's patent lawyer, Mushet claimed, had deprived him of an

opportunity of proving priority of invention against Bessemer. Mushet

was convinced that Martien's was the first in the field.[24]



[22] See Mining Journal, 1857, vol. 27, pp. 839 and 855. David

Mushet withdrew from the discussion after 1858 and his relapse

into obscurity is only broken by an appeal for funds for the

family of Henry Cort. A biographer of the Mushets is of the

opinion that Robert Mushet wrote these letters and obtained

David's signature to them (Fred M. Osborn, The story of the

Mushets, London, 1952, p. 44, footnote). The similarity in the

style of the two brothers is extraordinary enough to support this

idea. If this is so, Robert Mushet who disagreed with himself as

"Sideros" was also in controversy with himself writing as

"David."



[23] Mining Journal, 1856, vol. 26, p. 567.



[24] Ibid., pp. 631 and 647. The case of Martien will be

discussed below (p. 36). David Mushet had overlooked Bessemer's

patent of January 10, 1855.



Robert Mushet's campaign on behalf of his own claims to have made the

Bessemer process effective was introduced in October 1857, two years

after the beginning of Bessemer's experiment and after one year of

silence on Bessemer's part. Writing as "Sideros"[25] he gave credit to

Martien for "the great discovery that pig-iron can, whilst in the fluid

state, be purified ... by forcing currents of air under it ...," though

Martien had failed to observe the use of temperature by the "deflation

of the iron itself"; and for discovering that--



when the carbon has been all, or nearly all, dissipated, the

temperature increases to an almost inconceivable extent, so that

the mass, when containing only as much carbon as is requisite to

constitute with it cast steel ... still retains a perfect degree of

fluidity.



[25] Mining Journal, 1857, vol. 27, p. 723. Robert Mushet was a

constant correspondent of the Mining Journal from 1848. The

adoption of a pseudonym, peculiar apparently to 1857-1858 (see

Dictionary of national biography, vol. 39, p. 429), enabled him

to carry on two debates at a time and also to sing his own

praises.



This, says "Sideros," was no new observation; "it had been before the

metallurgical world, both practical and scientific, for centuries," but

Bessemer was the first to show that this generation of heat could be

attained by blowing cold air through the melted iron. Mushet goes on to

show, however, that the steel thus produced by Bessemer was not

commercially valuable because the sulphur and phosphorous remained, and

the dispersion of oxide of iron through the mass "imported to it the

inveterate hot-short quality which no subsequent operation could

expel." "Sideros" concludes that Bessemer's discovery was "at least for

a time" now shelved and arrested in its progress; and it had been left

"to an individual of the name of Mushet" to show that if "fluid

metallic manganese" were combined with the fluid Bessemer iron, the

portion of manganese thus alloyed would unite with the oxygen of the

oxide and pass off as slag, removing the hot-short quality of the iron.

Robert Mushet had demonstrated his product to "Sideros" and had

patented his discovery, though "not one print, literary or scientific,

had condescended to notice it."



"Sideros" viewed Mushet's discovery as a "spark amongst dry faggots

that will one day light up a blaze which will astonish the world when

the unfortunate inventor can no longer reap the fruits of his life-long

toil and unflinching perseverance." In an ensuing letter he[26] summed

up the situation as he saw it:



Nothing that Mr. Mushet can hereafter invent can entitle him to the

merit of Mr. Bessemer's great discovery ... and ... nothing that Mr.

Bessemer may hereafter patent can deprive Mr. Robert Mushet of having

been the first to remove the obstacles to the success of Mr. Bessemer's

process.



[26] Ibid., p. 823. Mushet's distinction between an inventor

and a patentee is indicative of the disdain of a son of David

Mushet for an amateur (see also p. 886).



Bessemer still did not intervene in the newspaper discussion; nor had

he had any serious supporters, at least in the early stage.[27]



[27] One William Green had commented extensively on David

Mushet's early praise of the Bessemer process and on his sudden

reversal in favor of Martien soon after Bessemer's British

Association address (Mechanics' Magazine, 1856, vol. 65, p. 373

ff.). Green wrote from Caledonian Road, and the proximity to

Baxter House, Bessemer's London headquarters, suggests the

possibility that Green was writing for Bessemer.



Publication in the Mining Journal of a list of Mushet's patents,[28]

evidently in response to Sideros' complaint, now presented Bessemer

with notice of Robert Mushet's activity, even if he had not already

observed his claims as they were presented to the Patent Office.

Mushet, said the Mining Journal--



appears to intend to carry on his researches from the point where

Mr. J. G. Martien left off and is proceeding on the Bessemer plan

of patenting each idea as it occurs to his imaginative brain. He

proposes to make both iron and steel but does not appear to have

quite decided as to the course of action ... to accomplish his

object, and therefore claims various processes, some of which are

never likely to realize the inventor's expectations, although

decidedly novel, whilst others are but slight modification of

inventions which have already been tried and failed.



[28] Mining Journal, 1857, vol. 27, p. 764.



The contemporary attitude is reflected in another comment by the

Mining Journal:[29]



Although the application of chemical knowledge to the manufacture

of malleable iron cannot fail to produce beneficial results, the

quality of the metal depends more upon the mechanical than the

chemical processes.... Without wishing in any way to discourage the

iron chemists, we have no hesitation in giving this as our opinion

which we shall maintain until the contrary be actually proved. With

regard to steel, there may be a large field for chemical research

... however, we believe that unless the iron be of a nature adapted

for the manufacture of steel by ordinary processes, the purely

chemical inventions will only give a metal of a very uniform

quality.



[29] Ibid., p. 764.



Another correspondent, William Green, was of the opinion that Mushet's

"new compounds and alloys," promised well as an auxiliary to the

Bessemer process but that "the evil which it was intended to remove was

more visionary than real." Bessemer's chief difficulty was the

phosphorus, not the oxide of iron "as Mr. Mushet assumes." This,

Bessemer no doubt would deal with in due course, but meanwhile he did

well "to concentrate his energies upon the steel operations," after

which he would have time to tackle "the difficulties which have so far

retarded the iron operations."[30]



[30] Ibid., p. 791.



Mushet[31] claims to have taken out his patent of September 22, 1856,

covering the famous "triple compound," after he--



had fully ascertained, upon the ordinary scale of manufacture that

air-purified cast-iron, when treated as set forth in my

specifications, would afford tough malleable iron ... I found,

however, that the remelting of the coke pig-iron, in contact with

coke fuel, hardened the iron too much, and it became evident that

an air-furnace was more proper for my purpose ... [the

difficulties] arose, not from any defect in my process, but were

owing to the small quantity of the metal operated upon and the

imperfect arrangement of the purifying vessel, which ought to be so

constituted that it may be turned upon an axis, the blast taken

off, the alloy added and the steel poured out through a spout ...

Such a purifying vessel Mr. Bessemer has delineated in one of his

patents.



[31] Ibid., p. 770 (italics supplied).



Mushet also claimed to have designed his own "purifying and mixing"

furnace, of 20-ton capacity, which he had submitted to the Ebbw Vale

Iron Works "many months ago," without comment from them. There is an

intriguing reference to the painful subject of two patents not

proceeded with, and not discussed "in the avaricious hope that the

parties connected with the patents will make me honorable amends ...

these patents were suppressed without my knowledge or consent." Lest

his qualifications should be questioned, Mushet concludes:



I do not profess to be an iron chemist, but I have undoubtedly made

more experiments upon the subject of iron and steel than any man

now living and I am thereby enabled to say that all I know is but

little in comparison with what has yet to be discovered.



So began Mushet's claim to have solved Bessemer's problem, a claim

which was to fill the correspondence columns of the engineering

journals for the next ten years. Interpretation of this correspondence

is made difficult by our ignorance of the facts concerning the control

of Mushet's patents. These have to be pieced together from his

scattered references to the subject.



His experiments were conducted, at least nearly up to the close of the

year 1856, with the cooperation of Thomas Brown of the Ebbw Vale Iron

Works.[32] The price of this assistance was apparently half interest in

Mushet's patents, though for reasons which Mushet does not explain the

deed prepared to effect the transfer was never executed.[33] Mushet

continued, however, to regard the patents as "wholly my own, though at

the same time, I am bound in honor to take no unfair advantage of the

non-execution of that deed." A possible explanation of this situation

may be found in Ebbw Vale's activities in connection with Martien and

Bessemer, as well as with an Austrian inventor, Uchatius.



[32] Ibid., p. 770.



[33] Ibid., p. 823.





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