and more, not to mention everything that might possibly be required for collecting specimens and making drawings.
This expedition succeeded in opening a whaling route and in bringing back collections and information about the people, animals and botany of the Arctic, even if not Jack Frost and the North Pole, as suggested in Cruikshank’s caricature of ‘Landing the Treasures, or Results of the Polar Expedition!!!’ (Fig. 6). They also inaugurated an age of polar exploration and science in which the names of Edward Parry, John and James Clark Ross (who were uncle and nephew), and John Franklin loomed large (Fig. 7). The most successful of the subsequent voyages was led by Parry, who passed through Lancaster Sound, Barrow Strait and Melville Island in 1819–20. Parry and his officers and men on the Hecla and the Griper were the only ones to receive one of the Board of Longitude’s Arctic rewards. On 4 September 1819, ‘At a quarter-past nine P.M., we had the satisfaction of crossing the meridian of 110° west from Greenwich, in the latitude of 74° 44' 20″; by which His Majesty’s ships, under my orders, became entitled to the sum of five thousand pounds’.10
Fig. 6 – ‘Landing the Treasures, or Results of the Polar Expedition!!!’, by George Cruikshank, 1819. This caricature shows the return of the crew of an Arctic voyage, parading their spoils, including newly-found flora and fauna as well as Jack Frost and the North Pole itself. They are being brought to the British Museum at the left of the picture, the curators of which are jumping with excitement
{National Maritime Museum, Greenwich, London}
However, as well as being significant for reaching extremes of geographical location and enduring an icy winter, these expeditions were important for their emphasis on scientific activity and rhetoric. The combination of heroic endeavour and scientific dedication is perfectly illustrated by a portrait of Commander James Clark Ross (Fig. 8), painted after his return from the Arctic expedition of 1829–33, in which he had succeeded in locating the north magnetic pole. It was exhibited in 1834 at the Society of British Artists as a portrait of the ‘Discoverer of the North Pole’. He is painted with Romantic looks – he was, according to John Franklin’s wife, ‘the handsomest man in the Navy’ – a sword and gleaming uniform against a black sky and icy background. He wears a bearskin, suggesting man’s taming of nature and triumph over the Arctic. Just as prominent are the Pole Star and a dip circle, used to measure magnetic inclination.
Fig. 7 – ‘Discoveries of Capts Ross, Parry & Franklin in the Arctic regions from the year 1818 to 1827’, from John Thomson’s New General Atlas (London, c.1830)
{National Maritime Museum, Greenwich, London}
Charting Africa
While polar expeditions began to fill in some of the blank spaces left on maps, there were many other areas for which charts existed but were considered inadequate. Unsurprisingly, survey voyages often focused on areas that were particularly dangerous or complex to navigate, as well as those which were strategically useful in military or trade contexts.
Somewhat different circumstances led to the charting of African coasts. In 1807, the British Parliament passed an Act designed to end the nation’s participation in the slave trade, and enforcing the ban became one of the duties of the Royal Navy. The Act stated that offending ships would be seized and fines enforced. It also offered prize money to those who successfully captured such ships. Individual incentives did not convince the Navy to commit much manpower to the policing of illegal trade and one of the problems facing such missions was a lack of good information about some of the key coastlines. The eastern coast of Africa was, though, to become of increasing concern once Britain took control of Mozambique in 1810 and began to strengthen its control of Indian Ocean traffic.
Fig. 8 – Commander James Clark Ross, by John R. Wildman, 1834
{National Maritime Museum, Greenwich, London}
The task of charting this coast fell to Captain William Fitzwilliam Owen (1774–1857), who already had considerable surveying experience and had learned some of his theory from Matthew Flinders, with whom he had been held prisoner on Mauritius between 1808 and 1810. After successful surveys of Indian Ocean islands and of the North American Great Lakes, Owen was appointed in 1821 to produce charts of Africa’s east coast between the boundary of Cape Colony in present-day South Africa and Cape Guardafui in present-day Somalia. Between 1822 and 1825, Owen’s squadron, formed of the sloop Leven and the brig Barracouta, surveyed around 20,000 miles of coast, which was later represented in almost 300 charts. It had been an arduous business, particularly because of the risk of fever: some seventy per cent of his officers died from disease.
Fig. 9 – Marine chronometer, by George Margetts, c.1790, used on the African surveys
{National Maritime Museum, Greenwich, London}
Fig. 10 – ‘West Coast of Africa, Sheet VII, ... surveyed by Captain W. F. W. Owen, Commander E. Belcher, and Lieutenant W. Arlett’, 1836
{National Maritime Museum, Greenwich, London}
Fig. 11 – Advertisement for Price’s candles, c.1850
{Lambeth Archives Department}
In 1825, on their return from the East Africa survey, Owen’s ships also carried out extensive surveys of the west coast of Africa (Fig. 10). They used a mixed bag of techniques on both surveys, with astronomical instruments, chronometers (Fig. 9) and, frequently, rockets all being used to fix positions and correct earlier data. Owen made much of the care and precautions taken to obtain the desired accuracy. He noted, for example, that good measurement of longitude ‘would depend on the uniformity of the rates of our chronometers’ and so ‘we made a resolution never to fire any of the great guns from the deck on which they were kept, if it could be avoided, nor indeed from either ship any at all, unless in cases where the public service absolutely demanded it’.11
Specialist astronomers and a botanist were on the voyage, but Owen complained that ‘Although we had a great many young officers, yet in astronomical science most of them were mere novices’. He therefore spent some time while they were stationed in Mozambique to rate the chronometers, enforcing ‘a continued course of observations, both by day and night ... principally with a view to acquire the use of the different instruments’.12 He felt his patience and caution here were fully justified, particularly in having a sceptical approach to the trustworthiness of the timekeepers.
Without considering the great improvements which have taken place in this instrument, and its supposed perfection, Captain Owen felt that, to place implicit confidence in it, might probably be fatal to the correctness and utility of our work: and the result proved the justice of this supposition, for, not one of our nine chronometers kept its rate without fluctuation, produced either by change of weather, climate, or position.13
While ‘some of this variation was very trifling’, it was ‘in all sufficient to produce much error, unless corrected by a great deal of care and attention’.14
The experience gained in the use of chronometers on this voyage was shared in an ‘Essay on Chronometers’ by Owen’s nephew, Richard. They both worried that, Setting out full instructions for their use, placement, rating and care, Richard Owen hoped to remedy the lack of this knowledge within the Navy, for, he said, the ‘consequence of their falling into the hands of persons ill instructed to their use, has in many cases proved fatal’.16
Fig. 12 – The Beagle in the Beagle Channel, Tierra del Fuego, by Conrad Martens, c.1834
{National Maritime Museum, Greenwich, London}
like many other new inventions, too much is perhaps expected from them, without paying that care and attention necessary to detect and guard against their wanderings, and those imperfections to which, as productions of human art, they must ever be liable.15
The work in East Africa had revealed to William Owen the ongoing extent of the slave trade. Strongly religious, he saw the eradication of ‘this hell-born traffic in slaves’ as a Christian duty.17 In an action undertaken on his own initiative and later disowned by the British government, Owen took the town
of Mombasa, then under siege by the Sultan of Oman, and, in exchange for a promise to abolish slavery, claimed to place it under British protection. On a later voyage, he also attempted to establish a colony for free slaves on the island of Fernando Po (now known as Bioko) but was thwarted by the fever endemic there.
Charts proved helpful in other approaches to countering the slave trade, including the use of steam vessels for river patrols. They also helped the growth of alternative trades that were being encouraged by presenting them as more lucrative, as well as safer and less objectionable ethically, than the slave trade. Palm oil was a West African product promoted in this way; it was used in Britain from the 1800s, first to make soap and then, replacing tallow, to make candles after a new process was developed in the 1820s. An 1840s advertisement from the company that pioneered this product, Price’s Patent Candle Company, based in Lambeth and Battersea, played out the drama for its potential customers (Fig. 11). Buying the new cleaner candles, and thus promoting the palm oil trade, was presented as a direct challenge to slavers.
Fig. 13 – The south-eastern part of Tierra del Fuego, surveyed by Captain Robert FitzRoy and the officers of HMS Beagle, 1830–34
{National Maritime Museum, Greenwich, London}
The voyages of the Beagle
Another area in which dedicated survey vessels were active was around Cape Horn, where the weather was dangerous and the coast rugged and complex. The most famous of all nineteenth-century survey vessels, HMS Beagle (Fig. 12), under Commander Pringle Stokes, headed there in 1826 with HMS Adventure, commanded by Captain Philip Parker King. In the difficult waters of Tierra del Fuego, Stokes committed suicide and Robert FitzRoy, the mathematically gifted naval cadet who was now a veteran of South American waters, took command of the Beagle.
The instructions issued to Captain King ordered him to survey the coasts of Patagonia and Tierra del Fuego (Fig. 13), and also
to avail yourself of every opportunity of collecting and preserving Specimens of such objects of Natural History as may be new, rare, or interesting; and you are to instruct Captain Stokes, and all the other Officers, to use their best diligence in increasing the Collections in each ship: the whole of which must be understood to belong to the Public.18
Fig. 14 – Portrait Cove, Beagle Channel, by Conrad Martens, c.1834
{National Maritime Museum, Greenwich, London}
Fig. 15 – Parallel rule given to John Lort Stokes by Robert FitzRoy, made by Nathaniel Worthington, c.1836. The engraved date, 1833, perhaps commemorates an important moment on their voyage, possibly Stokes’s 21st birthday (detail)
{National Maritime Museum, Greenwich, London}
The Beagle is best remembered today for its second voyage, on which the young Charles Darwin (1809–82) travelled as a geologist and naturalist. He and the artist Augustus Earle were taken on board by FitzRoy as private individuals, although the Navy paid for their food. Earle was later replaced by Conrad Martens, whose watercolours recorded the landscapes and people encountered (Fig. 14). While surveying took precedence, this, like other voyages, provided the opportunity for a whole range of information gathering and scientific work.
Hydrographic surveying was FitzRoy’s specialism and he led the work, as well as commanding and training the officers that shared the load. Those focusing on the survey were excused the usual duties of a naval vessel. One of the most talented was the young midshipman John Lort Stokes (1812–85), who became Assistant Surveyor and was, it seems, particularly close to FitzRoy. Possibly to mark retrospectively his twenty-first birthday and, the year after, ten years in the Navy, FitzRoy gave Stokes two high-quality parallel rules (Fig. 15) and a sextant (see Fig. 17), inscribed ‘Presented to J. Lort Stokes by Captn. R. FitzRoy’. Stokes received his technical education at sea, although he was able to introduce FitzRoy to a novel form of notation, which was said to be ‘very convenient and assists the memory more than any other’.19
Stokes was to serve on all three of the Beagle’s survey voyages, in 1826–30, 1831–36 and 1837–43, taking in the dangerous though strategically important areas of Cape Horn and Western Australia (Fig. 16). As he later wrote, over those eighteen years ‘my old friend’, the Beagle, had ‘extensively contributed to our geographical knowledge’. Stokes explicitly compared this record with that of a previous Beagle (1806) ‘that reaped golden opinions from her success in prize-making’ during the war.20 It was perhaps a plea that those serving on such scientific voyages should receive similar recognition to those involved in successful action. Stokes became lieutenant in 1837 but, even though he took command of the Beagle in 1841 during its third voyage, when Commander John Clements Wickham was invalided home, he was not promoted to captain until 1846.
On these voyages, Stokes naturally became familiar with a whole array of instruments, several of which would have been unknown to officers a century before (Fig. 17). On her second voyage, the Beagle carried no less than twenty-two chronometers, underlining the huge difference between specialist voyages for hydrographic surveying and most other naval activities. These did not all belong to the Navy, nor were they all simply for ascertaining the ship’s longitude – some were intended to be carried in small boats on survey activity and some were taken to be experimented on or tested themselves (Fig. 18).
* * *
FINDING A SHIP’S POSITION AT SEA
To find latitude
1. Measure the Sun’s meridian altitude, its maximum height above the horizon around local noon. (1), (2)
2. Use the tables to calculate the Sun’s true altitude, from which the latitude is derived. (3)
To find longitude
1. Find local time
Measure the altitude of the Sun or a star, timed with a watch.(1), (2), (4)
Use the tables in the Nautical Almanac to calculate local time and convert it to local mean time. (5), (6)
2. Find Greenwich time
a) By lunar distance (7), (8), (9)
As near simultaneously as possible, measure:
• the angular distance of the Moon from the Sun or a star
• the altitude of the Moon above the horizon
• the altitude of the Sun or star above the horizon
All observations are timed with a watch. (4)
Use the Nautical Almanac to convert the measured lunar distance to the true lunar distance, calculating its value as if viewed from the Earth’s centre. (10), (11)
Look up the true lunar distance in the Nautical Almanac to find the equivalent time at Greenwich. (12)
b) By chronometer (13)
Take the time from the timekeeper and correct for its rate, the amount it gains or loses each day.
3. Calculate the ship’s longitude
Work out the difference between local (ship) time and Greenwich time. (11)
Convert the time difference into an angle, one hour of time difference being equivalent to 15° of longitude.
If Greenwich time is greater than local time, the longitude is west of Greenwich. If Greenwich time is less than local time, the longitude is east of Greenwich.
(1) Octant, 1860
(2) Sketch from the log of the Owen Glendower, by John Lawrence King, 1846–47
(3) Tables Requisite, 1802
(4) Pocket chronometer, 1778
(5) Nautical Almanac, 1828
(6) Calculations, 1828
(7) Using lunar distance
{CollinsBartholomew Ltd 2014}
(8) Sketch from the log of the Owen Glendower, by John Lawrence King, 1846–47
(9) Sextant, c.1840
(10) Nautical Almanac, 1804
(11) Calculations, 1804
(12) Nautical Almanac, 1804
(13) Marine chronometer
* * *
Nevertheless, with so many to hand, the establishment of longitudes by chronometer was now seen as reliable enough for fixing positions on land. When discussing the difference in longitude between Rio de Janeiro and Montevideo with Francis Beaufort (1774–1857),
Hydrographer to the Navy, FitzRoy noted with pleasure that not only did his results agree closely with those of Captain King on the earlier voyage, but also that observations and calculations made by the Astronomers Royal at the Cape Observatory ‘confirm the Beagle’s Chronometers’.21 On his Australian survey, FitzRoy was instructed to check his chronometers at Parramatta Observatory, near Sydney, and then use them to determine the longitudes of various Pacific islands. This way, Beaufort said, ‘all those intervening islands will become standard points to which future casual voyagers will be able to refer their discoveries or correct their chronometers’. FitzRoy felt confident that he had created ‘a connected chain of meridian distances around the globe, the first that has ever been completed, or even attempted, by means of chronometers alone’.22
The timekeepers were, as always, used in tandem with other instruments and methods. The importance of the Nautical Almanac was clear when FitzRoy thanked Beaufort for sending him copies of the next year’s volume: ‘I was in dire alarm, thinking they would not arrive in time’. He added, too, that ‘My new Sextant (with an extra glass) answers extremely well, and is a general favourite. I can take back observation sights for time when the Sun is only 22° high, and agree exactly with sights taken at the opposite horizon by other observers’.23
Finding Longitude Page 17
