Captain Cook's Journal During His First Voyage Round the World. James Cook
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But of none of these lands was anything really known. Those who had visited them had merely touched. In no case had they gone round them, or ascertained their limits, and their descriptions, founded on brief experience, were bald and much exaggerated.
Let us turn to what was unknown.
This comprises the whole of the east coast of Australia, or New Holland, and whether it was joined to Tasmania on the south, and New Guinea to the north; the dimensions of New Zealand; New Caledonia and the New Hebrides, with the exception of the fact that the northern island of the latter existed; the Fiji Islands; Sandwich Islands; the Phoenix, Union, Ellice, Gilbert, and Marshall Groups, with innumerable small islands scattered here and there; the Cook Islands, and all the Society Islands except Tahiti. The majority of the Paumotu Group. The coast of North America north of 45 degrees north was unknown, and there was the great, undefined, and imaginary southern Continent to disprove.
Whether other voyages of exploration would have been undertaken one cannot say; but in 1768 the Royal Society put in a word.
A transit of Venus over the sun's disc was to occur in 1769, and astronomers were anxious to take advantage of it, the object of the observation being to ascertain the distance of the earth from the sun, the fundamental base line in all astronomical measurements, and which was very imperfectly known.
The Central Pacific afforded a favourable position, and the Royal Society memorialised the king to send a ship for the purpose. The request was granted, and at first Alexander Dalrymple, who had conducted marine surveys in the East Indies, and was known as a scientific geographer, was selected as observer. As, however, it was found that he also expected to command the ship, the Admiralty positively refused to have anything to do with him, and after some discussion James Cook was selected.
This says volumes for Cook's reputation at the time. To have risen absolutely from the ranks was a great deal, but to be chosen as a master, to command a ship, and undertake a scientific observation of this importance, was a most exceptional occurrence, and speaks well for the judgment of those who had the selection.
It seems that Mr. Stephens, the Secretary to the Admiralty, had much to do with it. How Stephens had become acquainted with Cook history does not relate, but doubtless his personal visits to the Admiralty in connection with the completion of his charts of Newfoundland, from which he returned every winter, had brought him into contact with the Secretary, who had clearly formed a high opinion of him.
Cook, we may be sure, jumped at the chance, and his pride must have been great when he found he was to receive a commission as Lieutenant.
This in itself was a most unusual step. The occasions on which a master had been transferred to the executive line of the Royal Navy were very rare, and many an admiral used his influence in favour of some deserving officer in vain.
This was not without good reason, as the whole training of the Master of those days was unfavourable to success in command of ships or men. The exception was, however, in this case amply justified.
Cook was allowed to choose his vessel, and bearing in mind the dangers of grounding in unknown seas, he pitched upon his old friends, the stoutly-built, full-bottomed colliers of the North Sea trade.
His ship, the Endeavour, was a Whitby built vessel of three hundred and seventy tons, and was known as H.M. Bark Endeavour, there being another vessel, a cutter, of the same name in the Royal Navy. She was brought to the dockyard at Deptford to fit out. Her appearance was, of course, wholly different from that of a vessel built as a man-of-war, and we shall see that this caused trouble at Rio Janeiro, where the combination of merchant build and officers in uniform in an armed ship, aroused suspicions in the mind of the Portuguese Viceroy.
It is nowhere directly stated whether the Endeavour was sheathed with copper or not; but as Cook in the account of his second voyage expresses himself as adverse to this method of protecting ships' bottoms, and the operation is recorded of heeling and boot topping, which was cleaning and greasing the part of the ship just below waterline, it may be concluded that her sheathing was wood.
She proved a most suitable vessel. The log states she was a little crank, but an admirable sea-boat. Her rate of sailing was of course, with her build, slow, but her strength and flat bottom stood her in good stead when she made acquaintance with a coral reef.
She mounted ten small carriage guns and twelve swivels.
Mr. Banks, a scientific botanist, afterwards well known as Sir Joseph Banks, and for a long time President of the Royal Society, a gentleman of private means, volunteered to accompany Cook, and took with him a staff of his own, of artists and others.
He also induced Dr. Solander, a Swedish naturalist, afterwards attached to the British Museum, to accompany him.
Mr. Charles Green, one of the assistants at the Royal Observatory at Greenwich, was sent as astronomer.
This scientific staff added much to the success of the expedition.
Banks and Solander, both men of observation, were able to collect specimens of natural history, and study the manners and customs of the natives with whom they came in contact, which neither the time at Cook's disposal nor his training enabled him to undertake; and though the Journal of the former has never yet been published, and cannot at the present time be traced, many interesting remarks were extracted by Dr. Hawkesworth from it and went far to make his account of the voyage complete.
Mr. Green also demands special notice.
One great question of the day amongst seamen and geographers was the discovering of some ready and sure method of ascertaining the longitude. Half the value of the explorations made up to this time had been lost from this want. The recognised means of finding longitude was by the observation of lunars; that is, accurately measuring the angular distance between the centres of the moon and of the sun, or of the moon and some star.
The motion of the moon is so rapid that this angular distance changes from second to second, and thereby, by previous astronomical calculation, the time at Greenwich at which its distance from any body is a certain number of degrees can be ascertained and recorded.
By well-known calculations the local time at any spot can be obtained, and when this is ascertained, at the precise moment that the angular distance of sun and moon is observed, the difference gives the longitude.
This seems simple enough, but there is a good deal of calculation to go through before the result is reached, and neither the observation nor the calculation is easy, especially with the astronomical tables of those days, and there were very few sailors who were capable of, or patient enough to make them, nor was the result, as a rule, very accurate. For one thing, the motions of the moon, which are extremely complicated, were not enough known to allow her calculated position in the heavens to be very accurate, and a very small error in this position considerably affects the time, and therefore the longitude.
Luckily for Cook, the Nautical Almanac had just been started, and contained tables of the moon which had not previously been available, and which much lightened the calculations.
The great invention of the chronometer, that is, a watch that can be trusted to keep a steady rate for long periods, was at this time completed by Harrison; but very few had been manufactured, and astronomers and sailors were slow to believe in the efficacy of this method of carrying time about with a ship. Thus Cook had no chronometer supplied to him.
Green had accompanied Mr. Maskelyne, afterwards Astronomer Royal, to Barbados in 1763 in H.M.S. Princess Louisa, in order to test Harrison's timekeeper, and also a complicated chair, from which it was supposed observations of Jupiter's satellites could be observed on board ship; and as this trial afforded the final triumph of the new method, one would have thought that on a voyage of circumnavigation he would have made every effort to get one of these watches.
Be this as it may, the Endeavour had no chronometer, and lunars were the mainstay of the expedition.
In these observations Green was indefatigable. Cook, an excellent observer himself frequently took part in them; but it was Green's especial business,