Instrument Breakage and Repair
Science in the British Empire was mainly practiced in the field. Fragile instruments had to be transported across rough seas and land, and then perform reliably in remote locations. Breakage and loss was a constant problem, and the challenges of maintenance and repair ever-present.
Instrument users were quick to point out their tools’ fragility when their work went awry, and to highlight their ingenuity when field repairs proved successful.
A broken sextant
The sextant was an essential navigational instrument, so large ships carried several as insurance against failure. As the example in Image 1 demonstrates, the telescope tube, horizon glass, and movable shades were particularly vulnerable to breakage.
When novice astronomer William Gooch joined the Vancouver Expedition in 1791, he must have cursed his luck when both his sextants were damaged beyond use only a month into his voyage. As he recorded in his journal:
“We arrived [in Rio] on the 27th Oct … I found the Micrometer screw on the Troughtons Sextant immoveable & about 10 days before I found one Corner of the Brass frame of the Dollond Sextant eaten thro with Rust & the Horizon Glass loose.”(1)
But in an extraordinary stroke of luck, Gooch soon found a man with suitable skills to repair both:
“Luckily one of Ramsdens Principal workmen was on board the Pitt as a convict he was brought on board the Daedalus & repaired both in my presence.”(1)
Remarkably, Gooch had discovered in Rio harbour a convict bound for Australia who had apprenticed under the preeminent London instrument-maker Jesse Ramsden—and the prisoner was willing to carry out the essential fixes!
Image 1: Sextant with broken telescope lens, on stand, by John Troughton, c. 1790 (Wh.1295).
Mountain trials
Survey work in the remote frontiers of colonial India proved particularly challenging for instrument users.
Taking accurate altitudes in the high Himalayas require surveyors to mountaineer whilst carrying fragile thermometers and barometers, the great majority of which did not survive the journey.
As the surveyor Alexander Gerard recorded in his journal on a particularly treacherous Himalayan expedition:
“[We] tent at Dangal, a small flat so called, on the left bank of the Ganges … On our return the barometer was deranged at this place.
'It is to be remarked, that on going up we did not fill the Barometers, fearing they might be broken, and the mercury spilt, of which we had very little; our store of it having been diminished by those various accidents to which every thing that can be lost, or broken, in these rough regions is subject.”(2)
Even instruments designed for the rugged survey work, like the ‘mountain barometer’ shown in Image 2, often broke in transit, leaving one surveyor to lament that “whoever wishes to get them from Europe, should order three times as many as he may want.”(3)
Image 2: Mountain barometer, by Troughton & Simms, London, c. 1840 (Wh.2883).
Boiling point
Critics of the mercury barometer argued that it was easier to measure atmospheric pressure (and hence altitude) from the boiling point of water using a device like the example shown in Image 3, a hypsometer, marketed in the 19th Century as ‘Wollaston’s thermometric barometer’.
Detractors, however, condemned Wollaston’s design as “of no use; you cannot take them out of their case without breaking,”(4) and advised merely using a good thermometer in a basin of water.
British explorer Richard Francis Burton was left measuring altitude from basic “bath thermometers” after a disastrous trek across East Africa in 1857:
“All along our way we were saddened by the sight of clean-picked skeletons, and here and there the swollen corpses of porters who had perished in this place by starvation. …
'When we arrived at Rufuta I found that nearly all our instruments had been spoilt or broken, the barometer had come to grief, no aneroid had been sent from Bombay, and we had chiefly to get on with two bath thermometers.”(5)
References
1.Quoted in: Richard Dunn, ‘Heaving a Little Ballast: Seaborne Astronomy in the Late-Eighteenth Century’, in: Marcus Granato & Marta C. Lourenço (eds.), Scientific Instruments in the History of Science: Studies in Transfer, Use and Preservation (Museu de Astronomia e Ciências Afins, 2014), 79–100, on p.86.
2.Cpt. J. A. Hodgson, ‘Journal of a Survey to the Heads of the Rivers, Ganges and Jumna’, Asiatick Researches, Vol. 14 (1822), 60–152, on pp.72-73.
3.L., ‘Mountain Barometers’, letter to the Editor of the Calcutta Journal of Politics and General Literature, 30 Jan. 1823, p.415.
4.Captain J. A. Hodgson, in an 1827 letter, as quoted in: R. H. Phillimore, Historical Records of the Survey of India, Vol. 3 (Dehra Dun: Survey of India, 1954), on p.222.
5.Extract from the private journal of Burton, as quoted in: Isabel Burton, The Life of Captain Sir Richard F. Burton, Vol. 1 (London: Chapman & Hall, 1893), on p.284.
Joshua Nall
Joshua Nall, ‘Instrument Breakage and Repair’, Explore Whipple Collections, Whipple Museum of the History of Science, University of Cambridge, 2020.