Go back to article: James Short and John Harrison: personal genius and public knowledge

Discovering Harrison’s watch

We can now consider the challenge facing the ‘Commissioners for the Discovery of Mr Harrison’s Watch’. How were they to effect this ‘discovery’, which meant literally the uncovering of the watch and the revealing of its secrets? How could anyone else come to ‘know’ what Harrison seemed to know, so as to make use of that knowledge? Merely looking inside would not be sufficient. Harrison would have to take the watch apart, demonstrate how it worked, be subject to detailed questioning by experts, instruct others in the successful manufacture of similar watches and, worst of all, as he saw it, collaborate with what were called ‘experimental exhibitions’ – a term he said left him completely baffled. There were many links here to the culture of public experiment in the eighteenth century and it is not irrelevant that mathematicians had involved themselves with making optical mirrors. They had experience of the difficulties of adequately capturing and codifying such acquired skill: we have noted that Newton himself had written, 'This Art of polishing will be better learnt by repeated Practice than by my description'.

The troubled and complex story of ‘discovering’ Harrison’s watch has been told elsewhere, but here we might consider Short’s situation through his time on the Commission. We have noted biographical links between Harrison and Short but here they were linked also through questions about the character of mechanical knowledge, the methodology of its communication and the possibilities for recording or codifying it in a set of rules or principles. This was precisely the burden of the ‘Commissioners for the Discovery of Mr Harrison’s Watch’ and James Short, who was one of their number, was involved on his own behalf with exactly these issues, though not under such public scrutiny as Harrison. At times his position between the trade, where manufacturing techniques were commercial assets, and the mathematical polishers, whose credit instead came from effective publication and recognition, was an uncomfortable one. How could Short make such superior telescopes, command such high prices, do so well in business? As a note added to the second (posthumous) edition of the Lectures on Natural and Experimental Philosophy of George Adams Junior put it: ‘From a principle unknown to a liberal philosopher, Mr. Short would not disclose the particular progresses by which he figured his metals; and at the time of his death they were supposed to die with him’ (Adams, 1799, 2, p 534).

There was a belief that Short had some secret method, formula or principle, either in the composition of his metal or in his technique for polishing, but no such secret was ever discovered, though it was looked for after his death. Gerard Turner has concluded that there was none: ‘It is very doubtful whether Short had any secret, other than his skill, dexterity and patience’ (Turner, 1969). MacLaurin had given just as simple an account as early as 1734: ‘He executes every part himself, and takes vast pains to make the instruments as perfect as possible’ (Smith, 1738, 2, pp 80–81).

In 1777 the physician John Mudge sought to publish the methods that were understood to be Short’s in a substantial paper in the Philosophical Transactions and such was the importance attached to this that he too was awarded the Copley Medal. In fact there was little in Mudge’s paper that was new and he was even doubtful whether such codification of mechanical skill was possible at all, admitting that his account could be only a partial one:

...I will describe it in the best manner I can; though many little circumstances which will be unavoidably omitted (and which at the same time are frequently essential to the success of a mechanic process) can only be supplied by actual experience. (Bennett, 2012, p 106)

Mudge’s attempts were taken up by the clergyman John Edwards, as the gentlemen mechanics continued their mirror-making to the end of the century, mired in attempts to express their acquired skills in words. Edwards agrees that: ‘a little Experience in these Matters will better suffice than a Volume written upon the Subject’ (Bennett, 2012, p 109). Most famously, William Herschel spent most of a lifetime acquiring this experience (still beginning by reading Smith’s Opticks) and made extensive and sustained efforts to prepare a treatise on polishing but never managed to complete it for publication. As a result, he too became suspected of keeping his methods secret and, like Short and Harrison, was criticised for this, though his manuscript record shows that he struggled and failed to achieve a secure codification that could have communicated his skills.

What has all this to do with Harrison? The familiar story sets the ambition, methodology and intellectual culture of eighteenth-century astronomy in opposition to the ethos and values  of mechanical horology. As this is being challenged and revised more generally, the present study shows that the conundrum that faced the Board of Longitude – how to reconcile a clear case of individual genius with the need for a universal practice – was not unknown to the community of astronomers. It might be expected for some of the most influential members of the Board to have looked for a solution to the longitude problem in some natural principle – a discovery or an application from the natural world – or in a codification that could capture and communicate a mechanical technique.  Yet in the contemporary development of the telescope they were more directly involved with the difficulty, perhaps the impossibility, of achieving any such codification. There the mathematicians themselves struggled to communicate the manual skills they had gained through their work with mirrors, while mechanics such as Dollond made less than convincing claims to a theoretical grounding for their mechanical practice.

Just as a longitude solution might have to depend uncomfortably on the particularity of mechanical genius, knowledge of some of the most elusive bodies in the heavens – such as nebulae and close double stars – depended on the seemingly arbitrary, manual talent and tactile sensitivity gained from many hours spent not studying optics but grinding and polishing mirrors. Members of the Board of Longitude, such as Robert Smith and James Bradley, had direct experience of such problems, while James Short had to negotiate his own path through the conundrum. He supplied the tools for revealing the heavenly bodies but the methods he used were largely unknown and had a contemporary reputation, almost certainly exaggerated, for secret particularity. In addition, Short’s empathy with Harrison surely derived some of its warmth from an intellectual culture that valued unschooled, unregulated, unspoilt, individual ‘genius’.

Component DOI: http://dx.doi.org/10.15180/140209/006