The Lighthouse Stevensons - Bella Bathurst [72]
Fresnel’s lenses also unwittingly became the subject of another of Robert’s battles. When he returned to Scotland intending to test the effectiveness of lenses for use in the Northern Lights he discussed his findings with a friend, Dr David Brewster. Brewster, he knew, was interested in optics and prided himself on his knowledge of fashionable new sciences. But instead of being curious about Fresnel’s works, Brewster was incensed. He claimed he had been the inventor of lenses for lighthouses, and produced as evidence a paper written some time previously advocating the use of ‘polyzonal lenses’ as ‘burning instruments’ for use in lights. He demanded that his lenses should be introduced to all the Scottish lights forthwith, and full credit given to him for their invention. Robert ignored Brewster’s blusterings, but recommended to the Commissioners that lenses on the Fresnel model should be tested and then introduced gradually. A prototype was set up at Inchkeith light, and, though partially successful, needed modifications and was removed again for the time being. The Commissioners asked for further tests. Robert, being habitually cautious about major changes in designs and lighting, accepted their suggestions and began the slow process of adapting the lights for his purposes.
The NLB’s prudence did not satisfy Brewster. In 1827, two years after the dispute had begun, he presented a paper to the Royal Society of Edinburgh ‘On the theory and Construction of Polyzonal lenzes and their combination with Mirrors for the purpose of illumination in lighthouses’. In it, he accused the Commissioners of pandering to ‘sordid interests’, and Robert himself of professional malpractice. Robert, furious, wrote to Brewster demanding a copy of the paper, and insisting that the ‘mistakes’ should be removed. Brewster refused. Robert wrote back, complaining that this was not the kind of behaviour expected of Royal Society members, and insisting that ‘I have only again to state that I had no other object than to correct inaccuracies which seem to have crept into it.’ Brewster again refused to let Robert see the paper, so Robert wrote to the RSE, demanding that the paper should be vetted by them and possibly withdrawn until the dispute had been settled. The RSE replied that Brewster’s version should stand. Robert, reduced to impotent pique, announced that he ‘decline[d] having anything further to do with the paper’.
It was soon evident that Brewster was not the kind of amiable opponent that Rennie had once been. He had a bilious temper and an infinite capacity to nurse a grudge. Once provoked, he considered himself engaged in a justified war for lenses over reflectors. In 1833, Robert finally tested the different equipment by setting up a display of French lenses, English lenses and Scots reflectors twelve miles from Edinburgh, which were viewed by the Commissioners from the top of Calton Hill. The Fresnel lenses, it was concluded, gave the strongest, steadiest beams, far superior to even the best of reflectors. Brewster, who appeared on the hill to press his case, wrote immediately to the Commissioners insisting that the results proved Robert’s reactionary intentions and demanding that he, Brewster, should be appointed to the Northern Lighthouse Board to fit and supervise the new lenses. In a subsequent letter, his enthusiasm ran away with him and he declared that lenses should be fitted forthwith in every light in Scotland, that gas should be substituted for oil and, with a final flourish, that all the existing Scottish lighthouses should be ‘dismantled’ and rebuilt to suit the new specifications. The Commissioners, infuriated by Brewster’s demands, delayed the results of their enquiries still further. Brewster, considering that the delays only proved the criminal intentions of the Board, enlisted Westminster in his cause.
Joseph Hume, a radical English MP, had made it