We continued to steer south-eastward, round all these islands, having a fresh gale at west-south-west with squally weather; and at noon our situation was in

Latitude observed, 39 deg. 35' Longitude by time keepers, 146 30 Rodondo bore N. 15 W. Sir R. Curtis' Island, the peak, dist. 7 miles, N. 46 E. (The Devil's Tower being nearly on with the north side.) Two pointed rocks, N. 57 deg. and 62 E.

Wilson's Promontory was no longer visible; but from the best bearings I had been able to obtain in such blowing weather, its south-eastern extremity lies in latitude 39 deg. 111/2' south, and longitude 146 deg. 24' east.

Not seeing any more islands to the southward from the masthead, we bore away east soon after noon to make Kent's Groups; and before three o'clock they both came in sight, as did an island to the northward, which seems to have been one of the small cluster discovered by Mr. John Black, and named Hogan's Group. The longitude by time keepers at this time was 146 deg. 58' east, and the following bearings were taken:

Sir R. Curtis' Island, the peak, N. 71 deg. W. Hogan's highest Island, from the mast head, N. 5 E. Kent's large Group, south end of the eastern I. N. 70 E. Small Group, dist. 6 or 7 miles, hiding the north-west end of the large group, N. 52 deg. to 45 E.

In steering past the south sides of the two groups at the distance of four to six miles, I was enabled to correct their positions; and also that of the pyramid, which was set at S. 41/2 deg. E. ten miles at four o'clock. When these lands had been laid down in the Francis and Norfolk in 1798, it was without the assistance of a time keeper, and therefore liable to considerable errors in longitude.

At five in the evening I thought myself fortunate to get a sight of Furneaux's great island through the haze; and also of a small, craggy isle which had been before fixed relatively to the inner Sister. To obtain the positions of these places by our timekeepers was to me an important object; since they were connected with the former survey of Furneaux's Islands and the north-eastern part of Van Diemen's Land. The bearings taken at five were,

Furneaux's great I., hills on the west part, S. 48 deg. E. Small craggy isle, S. 69 E. Kent's large Group, extremes, N. 7 deg. to 47 W. Small Group, the largest isle, N. 77 W. A small rock, not seen before, N. 88 E.

The hills upon Furneaux's great island, which I believe, but could not certainly ascertain to have been upon the westernmost point, will therefore lie very nearly S. 48 deg. E., from the bluff south-west end of Kent's large Group, instead of S. 38 deg. E., as before marked. This places the great island 10' of longitude further east from the group, than was given by my run in the Francis during the night of Feb. 8, 1798.

We passed to the northward of the small new rock at the distance of three miles, and I judged it to lie four, or four-and-half leagues from the eastern side of Kent's large Group. No kind of danger was observed between them, but it was then nearly dark; and the wind being fresh and favourable, and not having more than ten days provisions in the ship, I felt it necessary to leave this and some other parts of Bass' Strait to a future examination; and we steered onward, east-north-east for Port Jackson.

WEDNESDAY 5 MAY 1802

At daylight of the 5th the course was altered more northward; and at noon, land was seen from the mast head to the north-north-west, probably some of the hills at the back of the Long Beach, and distant not less than twenty leagues: our latitude was 38 deg. 32' south and longitude 149 deg. 35' east. The wind had then moderated and having shifted to north-west we kept close up to make Cape Howe. At four, hove to and sounded, but no bottom could be had with 90 fathoms; the land extended in patches from west-north-west distant twenty-five or more leagues to near the Ram Head at north; and consequently the hills at the back of the Long Beach must be of considerable elevation, superior to any other land near the sea in the southern, or perhaps any part of New South Wales.

THURSDAY 6 MAY 1802

On the wind shifting to the east side of north, next day, I tacked to get in with the land; being desirous of running near to as much of the coast, and correcting its longitude in our way to Port Jackson, as could be done without loss of time; but at noon the wind veered back, and our north-eastern course was resumed. The land could not then be further distant than nine or ten leagues; but no part of it was in sight, nor from the dullness of the weather could any observation be taken.

[EAST COAST. PORT JACKSON.]

FRIDAY 7 MAY 1802

After a squally night the wind fixed at west-by-north; and at daybreak of the 7th the land was visible from west to north-west, and our course was parallel to it (Atlas Plate VIII). At noon, the latitude was 36 deg. 24' south, and longitude 151 deg. 16' east; Mount Dromedary was in sight bearing N. 85 deg. W., and by the difference of longitude, was distant fifty-two miles: I estimate its highest south part to lie in 36 deg. 19' south, and 150 deg. 11' east. The wind returned to the north-west in the afternoon, and we lost sight of the land; but becoming fairer afterwards, and the southern current not having much strength, by four next day [SATURDAY 8 MAY 1802] the heads of Port Jackson were in sight. At dusk the flag-staff upon the South Head bore west-south-west, and our distance from the shore was seven or eight miles.

I tried to beat up for the port in the night, being sufficiently well acquainted to have run up in the dark, had the wind permitted; but we were still to leeward in the morning [SUNDAY 9 MAY 1802], and Mr. Westall made a good sketch of the entrance (Atlas Plate XVIII. View 1). At one o'clock, we gained the heads, a pilot came on board, and soon after three the Investigator was anchored in Sydney Cove.

There was not a single individual on board who was not upon deck working the ship into harbour; and it may be averred that the officers and crew were, generally speaking, in better health than on the day we sailed from Spithead, and not in less good spirits. I have said nothing of the regulations observed after we made Cape Leeuwin; they were little different from those adopted in the commencement of the voyage, and of which a strict attention to cleanliness and a free circulation of air in the messing and sleeping-places formed the most essential parts. Several of the inhabitants of Port Jackson expressed themselves never to have been so strongly reminded of England as by the fresh colour of many amongst the Investigator's ship's company.

So soon as the anchor was dropped, I went on shore to wait upon his Excellency Philip Gidley King, Esq., governor of New South Wales, and senior naval officer upon the station; to whom I communicated a general account of our discoveries and examinations upon the South Coast, and delivered the orders from the Admiralty and Secretary of State. These orders directed the governor to place the brig Lady Nelson under my command, and not to employ the Investigator on other service than that which was the object of the voyage; and His Excellency was pleased to assure me that every assistance in the power of the colony to render should be given to forward a service so interesting to his government, and to himself. The Lady Nelson was then lying in Sydney Cove; but her commander, lieutenant Grant, had requested permission to return to England, and had sailed six months before.

Besides the Lady Nelson, there were in the port His Majesty's armed vessel Porpoise, the Speedy, south-whaler, and the Margaret privateer; also the French national ship Le Naturaliste, commanded by captain Hamelin, to whom I communicated captain Baudin's intention of coming to Port Jackson so soon as the bad weather should set in. Le Geographe's boat had been picked up in Bass' Strait by Mr. Campbell of the brig Harrington, and the officers and crew were at this time on board Le Naturaliste.

MAY 1802

The duties required to fit the ship for prosecuting the voyage with success being various and extensive, Cattle Point, on the east side of Sydney Cove, was assigned to us by the governor for carrying on some of our employments, whilst others were in progress on board the ship and in the dockyard. On the morning after our arrival we warped to a convenient situation near the point, and sent on shore the tents, the sailmakers and sails, and the cooper with all the empty casks. Next day the observatory was set up, and the time-keepers and other astronomical instruments placed there under the care of lieutenant Flinders, who, with Mr. Franklin, his assistant, was to make the necessary observations and superintend the various duties carrying on at the same place; and a small detachment of marines was landed for the protection of the tents.

I had found the barricade of the quarter deck to stand so high, as to be not only an obstacle to beating to windward, but a great inconvenience to surveying the coast; for when the wind was on the side next to the land, there were no means of taking bearings over it but by standing on the top of the binnacle; or otherwise by removing the compass to different places, which I had found could not be done without materially changing the variation. These inconveniences being stated to the governor, his permission was obtained to reduce it so low as that it might be overlooked in all cases; and an order was given that four convict carpenters, and such other assistance from the dockyard should be furnished as was necessary.

To supply the place of the cutter we had lost at the entrance of Spencer's Gulf, I contracted for a boat to be built after the model of that in which Mr Bass made his long and adventurous expedition to the strait. It was twenty-eight feet seven inches in length over all, rather flat floored, head and stern alike, a keel somewhat curved, and the cut-water and stern post nearly upright; it was fitted to row eight oars when requisite, but intended for six in common cases. The timbers were cut from the largest kind of banksia, which had been found more durable than mangrove; and the planking was of cedar. This boat was constructed under the superintendance of Mr. Thomas Moore, master builder to the colony; and proved, like her prototype, to be excellent in a sea, as well as for rowing and sailing in smooth water. The cost at Port Jackson was no more than L30.; but this was owing to some of the materials being supplied from the public magazines.

Whilst these branches of our refitment were going on, a thorough examination was made and survey taken of all the ship's stores; as well for the purpose of sending away those unserviceable and replacing them with others so far as they could be obtained, as with a view to enable the warrant officers to pass their accounts and obtain their pay up to this time; a precaution which the nature of our voyage rendered more peculiarly necessary. After the surveys were ended, the seamen were employed in stripping and re-rigging the masts, and preparing the hold to receive a fresh stock of provisions and water; the naturalist and his assistants, as also the two painters, made excursions into the interior of the country; and my time was mostly occupied in constructing the fair charts of our discoveries and examinations upon the south coast, for the purpose of their being transmitted to the secretary of the Admiralty.

JUNE 1802

On the 4th of June, the ship was dressed with colours, a royal salute fired, and I went with the principal officers of the Investigator to pay my respects to His Excellency the governor and captain-general, in honour of HIS MAJESTY'S birth day. On this occasion, a splendid dinner was given to the colony; and the number of ladies and civil, military, and naval officers was not less than forty, who met to celebrate the birth of their beloved sovereign in this distant part of the earth.

On the 6th, the Speedy, south-whaler, sailed for England. By Mr. Quested, the commander, I transmitted to the Admiralty an account of my proceedings upon the south coast of Terra Australis; but the charts being unfinished, were obliged to be deferred to a future opportunity. To the Astronomer Royal I sent Arnold's time keepers, No. 82 and 176, which had stopped; together with a statement of the principal astronomical observations hitherto made, and an account of Earnshaw's two time keepers, No. 543 and 520, which continued to perform well.

Captain Baudin arrived in Le Geographe on the 20th, and a boat was sent from the Investigator to assist in towing the ship up to the cove. It was grievous to see the miserable condition to which both officers and crew were reduced by scurvy; there being not more out of one hundred and seventy, according to the commander's account, than twelve men capable of doing their duty. The sick were received into the colonial hospital; and both French ships furnished with everything in the power of the colony to supply. Before their arrival, the necessity of augmenting the number of cattle in the country had prevented the governor from allowing us any fresh meat; but some oxen belonging to government were now killed for the distressed strangers; and by returning an equal quantity of salt meat, which was exceedingly scarce at this time, I obtained a quarter of beef for my people. The distress of the French navigators had indeed been great; but every means were used by the governor and the principal inhabitants of the colony, to make them forget both their sufferings and the war which existed between the two nations.*

[* These liberal proceedings, which do so much honour to governor King and the colonists, are handsomely acknowledged by M. Peron in his account of the French voyage.]

JULY 1802

His Excellency, Governor King, had done me the honour to visit the Investigator, and to accept of a dinner on board; on which occasion he had been received with the marks of respect due to his rank of captain-general; and shortly afterward, the Captains Baudin and Hamelin, with Monsieur Peron and some other French officers, as also Colonel Paterson, the lieutenant-governor, did me the same favour; when they were received under a salute of eleven guns. The intelligence of peace, which had just been received, contributed to enliven the party, and rendered our meeting more particularly agreeable. I showed to Captain Baudin one of my charts of the south coast, containing the part first explored by him, and distinctly marked as his discovery. He made no objection to the justice of the limits therein pointed out; but found his portion to be smaller than he had supposed, not having before been aware of the extent of the discoveries previously made by Captain Grant. After examining the chart, he said, apparently as a reason for not producing any of his own, that his charts were not constructed on board the ship; but that he transmitted to Paris all his bearings and observations, with a regular series of views of the land, and from them the charts were to be made at a future time. This mode appeared to me extraordinary, and not to be worthy of imitation; conceiving that a rough chart, at least, should be made whilst the land is in sight, when any error in bearing or observation can be corrected; a plan which was adopted in the commencement, and followed throughout the course of my voyage.

Amongst our employments was that of fitting up a green house on the quarter deck, and sawing plank to make boxes for the reception of such plants as might be found by the naturalist, and thought worthy of being transported to His Majesty's botanic garden at Kew. This green house had been received at Sheerness, and stowed away in pieces; but I saw that when filled with boxes of earth, the upper works of the ship, naturally very weak, would be incapable of supporting the weight; and that in bad weather, we should be obliged to throw it over board for the safety of the ship. I therefore proposed its reduction to two-thirds of the size; and Mr. Brown being of opinion it would then contain all the plants likely to be collected in any one absence from Port Jackson, it was reduced accordingly; and the feet lowered down close to the deck. This arrangement required an alteration in the tiller, and a short one, with two arms, was fitted to the after part of the rudder head; with which expedient, and leading the main braces forward, the green house was not likely to cause much inconvenience to the working of the ship. The plants already collected on the South Coast had been landed on our arrival, in good order; and deposited in the governor's garden until such time as, the objects of the voyage being completed, we should be ready to sail for England.

The ship had never made more than three inches of water in an hour, after leaving the Cape of Good Hope; so that much caulking was not required, either within or out board. What was found necessary, was finished by the middle of July, at the same time with the barricading of the quarter deck; and the masts being then new rigged, and holds nearly completed with water and provisions, the sails were bent and the ship was painted. On the 21st, the last bag of bread and turn of water were received, the new whale boat was brought off, and we dropped down the harbour; being then ready for going to sea next morning.

In consequence of the directions given by His Majesty's principal Secretary of State for the Colonies, the Lady Nelson, a brig of sixty tons, commanded by Acting-Lieutenant John Murray, was placed under my orders, as a tender to the Investigator. This vessel was fitted with three sliding keels; and built after the plan of that ingenious officer commissioner (now vice-admiral) Schanck. When the sliding keels were up, the Lady Nelson drew no more than six feet water; and was therefore peculiarly adapted for going up rivers, or other shallow places which it might be dangerous, or impossible for the ship to enter. Mr Murray's crew was mostly composed of convicts; and having no officer in whom he could place entire confidence, I lent to him Mr Denis Lacy, one of my young gentlemen acquainted with the management of a time keeper, to act as his chief mate.

The price of fresh meat at Port Jackson was so exorbitant, that it was impossible to think of purchasing it on the public account. I obtained one quarter of beef for the ship's company, in exchange for salt meat, and the governor furnished us with some baskets of vegetables from his garden; and in lieu of the daily pound of biscuit, each man received a pound and a quarter of soft bread, without any expense to government. But with these exceptions, I was obliged to leave the refreshment of the people to their own individual exertions; assisting them with the payment due for savings of bread since leaving the Cape of Good Hope, and the different artificers with the money earned by their extra services in refitting the ship. Fish are usually plentiful at Port Jackson in the summer, but not in the winter time; and our duties were too numerous and indispensable to admit of sending people away with the seine, when there was little prospect of success; a few were, however, occasionally bought alongside, from boats which fished along the coast.

In purchasing a sea stock for the cabin, I paid L3 a head for sheep, weighing from thirty to forty pounds when dressed. Pigs were bought at 9d. per pound, weighed alive, geese at 10s. each, and fowls at 3s.; and Indian corn for the stock cost 5s. a bushel.

To complete the ship's provisions, I entered into a contract for 30,000 pounds of biscuit, 8000 pounds of flour, and 156 bushels of kiln-dried wheat; but in the meantime, the ship Coromandel brought out the greater part of the twelvemonths' provisions, for which I had applied on sailing from Spithead; and the contractor was prevailed upon to annul that part of the agreement relating to flour and wheat. The biscuit cost 33s. per hundred pounds; and considering that the colony was at short allowance, and that the French ships were to be supplied, it was a favourable price. From two American vessels which arrived, I purchased 1483 gallons of rum at 6s. 6d. per gallon; which, with what remained of our former stock was a proportion for twelve months. In other respects our provisions were completed from the quantity sent out from England; and the remaining part was lodged in the public stores, in charge of the commissary, until our return.

In addition to the melancholy loss of eight officers and men, at the entrance of Spencer's Gulf, and the previous deficiency of four in the complement, I found it necessary to discharge the man who had been bitten by a seal at Kangaroo Island, as also a marine, who was invalided; so that fourteen men were required to complete my small ship's company. Mr John Aken, chief mate of the ship Hercules, was engaged to fill the situation of master, and five men, mostly seamen, were entered, but finding it impossible to fill up the complement with free people, I applied to the governor for his permission to enter such convicts as should present themselves, and could bring respectable recommendations. This request, as every other I had occasion to make to His Excellency, was complied with; and when the requisite number was selected, he gave me an official document, containing clauses relative to these men, well calculated to ensure their good conduct. As this document may be thought curious by many readers, it is here inserted; premising, that the men therein mentioned, with the exception of two, were convicts for life.

By His Excellency Philip Gidley King, Esq., captain-general and governor in chief, in and over His Majesty's territory of New South Wales and its dependencies, etc., etc., etc.

"Whereas Captain Matthew Flinders, commander of His Majesty's ship Investigator, has requested permission to receive on board that ship the undermentioned convicts as seamen, to make up the number he is deficient. I do hereby grant Thomas Toney, Thomas Martin, Joseph Marlow, Thomas Shirley, Joseph Tuzo, Richard Stephenson, Thomas Smith, Francis Smith, and Charles Brown permission to ship themselves on board His Majesty's ship Investigator, and on the return of that ship to this port, according to Captain Flinders' recommendation of them, severally and individually, they will receive conditional emancipations or absolute pardons, as that officer may request.

"And in the interim I do, by virtue of the power and authority in me vested, grant a provisional-conditional emancipation to the said Thomas Toney, etc.; for the purpose of their being enabled to serve on board His Majesty's said ship Investigator, whilst in the neighbourhood of this territory; which conditional emancipation will be of no effect, in case any of those named herein do individually conduct themselves so ill, as to put it out of captain Flinders' power to recommend them for a conditional or absolute pardon on his return to this port.

"Given under my hand and seal at government house Sydney, in New South Wales, this 15th day of July, in the year of our Lord 1802. (Signed) Philip Gidley King, (L. S.)"

Several of these men were seamen, and all were able and healthy; so that I considered them a great acquisition to our strength. With respect to themselves, the situation to which they were admitted was most desirable; since they had thereby a prospect of returning to their country, and that society from which they had been banished; and judging from the number of candidates for the vacancies, such was the light in which a reception on board the Investigator was considered in the colony. When the master was entered, one of the men, being over the complement, was sent to the Lady Nelson, with a reserve of the privilege above granted.

I had before experienced much advantage from the presence of a native of Port Jackson, in bringing about a friendly intercourse with the inhabitants of other parts of the coast; and on representing this to the governor, he authorised me to receive two on board. Bongaree, the worthy and brave fellow who had sailed with me in the Norfolk, now volunteered again; the other was Nanbaree, a good-natured lad, of whom Colonel Collins has made mention in his Account of New South Wales.

My instructions directed me to consult with Governor King upon the best means of proceeding in the execution of the voyage; they also pointed out my return to the south coast, as the first step after refitting the ship at Port Jackson; but His Excellency was of opinion, as well as myself, that it would be unsafe to do this in the middle of the winter season; and that to remain six months in port waiting for the fine weather would be a sad waste of time; I had, besides, left very little of importance to be examined upon the south coast, a circumstance which the instructions had not contemplated. Upon all these considerations, it was decided to proceed to the northward—examine Torres' Strait and the east side of the Gulf of Carpentaria before the north-west monsoon should set in—proceed as I might be able during its continuance—and afterwards explore the north and north-west coasts; returning to Port Jackson when, and by such route as might be found most advisable, and conducive to the general purposes of the voyage.

It was probable that the north-west monsoon would not set in before the beginning of November; I therefore intended to examine such parts of the east coast of New South Wales in my way to the northward, as had been passed by Captain Cook in the night, and were not seen in my expedition with the Norfolk sloop in 1799. The openings of Keppel and Shoal-water Bays, and the still larger of Broad Sound, I was also anxious to explore; in the hope of finding a river falling into some one of them, capable of admitting the Lady Nelson into the interior of the country. These desirable objects I expected to accomplish before the approach of the monsoon would call me into the Gulf of Carpentaria.

The French ships were in no forwardness for sailing; and it was understood that Captain Baudin intended sending back Le Naturaliste to France, by the way of Bass' Strait, so soon as the season should be favourable. He had purchased a small vessel of between thirty and forty tons at Sydney, to serve him as a tender; and he told me that we should probably meet in the Gulf of Carpentaria in December or January. I understood that he meant to return to the south coast, and after completing its examination, to proceed northward, and enter the Gulf with the north-west monsoon; but it appeared to me very probable, that the western winds on the south coast would detain him too long to admit of reaching the Gulf of Carpentaria at the time specified, or at any time before the south-east monsoon would set in against him.

Before leaving Sydney Cove, I placed in the hands of governor King two copies of my chart of the south coast of Terra Australis, in six sheets; with three other sheets of particular parts, on a large scale. One copy I requested him to send with my letters to the secretary of the Admiralty, by the first good opportunity that offered; the other was to remain in his hands until my return, or until he should hear of the loss of the Investigator, when it was also to be sent to the Admiralty.

During our stay of twelve weeks at Port Jackson, there were not many days favourable to our pursuits at the observatory, the weather being dull and rainy for the greater part of the time; by watching all opportunities however, a sufficient number of observations were obtained to show the rates of the time keepers, and to answer the purposes of geography and navigation.

The Latitude of Cattle Point, from thirty meridian altitudes in an artificial horizon, of which fourteen were taken by Mr. Crosley and seven by me in 1795, and nine by lieutenant Flinders at this time, is 33 deg. 51' 45.6" S.

Longitude from forty-four sets of distances of the sun and moon, of which the individual results are given in Table VI of the Appendix to this volume, 151 deg. 11' 49" E.*

[* In 1795 and 1796 I took sixty sets of distances upon Cattle Point, an equal number on each side, which gave the longitude 151 deg. 17' 12"; but these observations not having been calculated with great nicety, nor corrected for the errors of the lunar and solar tables, the result is not considered to be of equal authority with that given above. The present admiral D'ESPINOSA, when an officer in the voyage of Malaspina, observed an eclipse of the sun at Port Jackson, and occultations of the first and second satellites of Jupiter, from which he deduces the longitude of the town of Sydney to be 151 deg. 12' 45" east of Greenwich; not differing more than a minute of longitude from the above forty-four sets of corrected lunar observations.]

This position of Cattle Point, being reduced to the entrance of Port Jackson, will be for the Flag staff on the south head, latitude 33 deg. 511/2' south, longitude 151 deg. 161/2 east.

Ramsden's universal theodolite was set up at the observatory, and intended to be used as a transit instrument; but from the unfavourable state of the weather and my numerous occupations, it was not adjusted to the meridian; and the rates of the time keepers were therefore deduced from equal altitudes, taken with a sextant and artificial horizon in the usual way. Their errors from mean Greenwich time, at noon there July 18, and the mean rates of going in the last fifteen days, which were selected as the best, were as under:

Earnshaw's No. 543, slow Oh 16' 39.72" and losing 8.63" per day. Earnshaw's No. 520, slow 1 18 53.00 and losing 19.52 per day.

The longitude of Cattle Point, given by the time keepers with the Kangaroo-Island rates on May 10th, the first day of observation after our arrival, was by

No. 543 151 deg. 31' 21" east No. 520 151 26 49 east.

The mean is 17' 16" more than deduced from the lunar observations; and when rates are used equally accelerating from those at Kangaroo Island, to what were found on first arriving at Port Jackson, the longitude by the time keepers would still be 14' 57.4" to the east; so that they appear to have gone less regularly during this passage than before. In fixing the longitudes of places between the two stations, the time keepers with their accelerated rates have been used; and the error of 14' 57.4" has been corrected by quantities proportionate to the times of observation, between April 6 at Kangaroo Island, and May 9 at Port Jackson.

The mean dip of the south end of the needle at Cattle Point was 62 deg. 52'

Variation of the compass, observed by lieutenant Flinders on Garden Island in the following year, 8 deg. 51' east.

No remarks were made at this time upon the tide; but it is known to be high water in Port Jackson about eight hours and a quarter after the moon's passage over and under the meridian; and the usual rise to be between four and six or seven feet. When high water takes place between three or four in the afternoon and one or two in the morning, it rises from six to eighteen inches higher than the preceding flood; and the following ebb descends a few inches lower than that which preceded the high tide.

The range of the thermometer on board the ship, was from 51 deg. to 69 deg.; and nearly the same on shore. The mercury in the barometer stood from 29.60 to 30.36 inches; but it was remarkable that it stood lowest in the fine weather, when the wind came from the westward off the land, and was highest in the rainy, squally weather, with the wind from the sea. According to the information communicated by colonel W. Paterson, F. R. S., commander of the troops at Port Jackson, this relation between the mercury and the weather was general here in the winter season, when the eastern winds bring rain with them; and I had frequent occasion to remark upon the South Coast, that sea winds raised the mercury in the barometer, whilst those from the land, even with fine weather, caused it to descend.

CHAPTER XI

Of the winds and currents on the south coast of Terra Australis, and in Bass' Strait. Usual progress of the gales. Proper seasons for sailing eastward, and for going westward: best places of shelter in each case, with some instructions for the Strait.

[SOUTH COAST. WINDS AND CURRENTS]

Before entering upon the second part of the voyage, it seems proper to give an account of the winds and currents which prevailed upon the South Coast; and to add thereto such other general information as may be useful in rendering the navigation more safe and expeditious, both along the coast and through Bass' Strait.

The rate and direction of the currents here described, are deduced from the daily positions of the ship by astronomical observation, compared with those given by a log kept in the common way, but with somewhat more than common attention. In the observations, however, there may be some errors, and a log cannot be depended upon nearer than to five miles in the distance, and half a point in the course for the twenty-four hours; and consequently this account of the currents must be taken as subject to the sum, or to the difference of the errors in the observations and log; though it is probable they may have been diminished by taking the medium of several days, which has always been done where it was possible.

Besides the difficulty there is in obtaining the exact rate and direction of a current, it is known that a continuance of the wind in any particular quarter may so far change its rate of moving, and even its direction, that at another time it may be found materially different in both. Of the probability of these changes the commander of a ship must form his own judgment, from the winds he may have previously experienced; and he will consider what is here said upon both winds and currents, as calculated and intended to give him a general notion, and no more, of what may usually be expected upon the South Coast.

(Atlas Plate I.)

Several days before making Cape Leeuwin, I experienced a current setting to the northward, at the rate of twenty-seven miles per day; but at the mean distance of forty leagues, west-south-west from the cape, the current ran north-east, twenty-two miles; and when the ship got in with the South Coast, I found it setting N. 70 deg. E., at the average rate of twenty-seven miles per day: this was in the month of December. On approaching Cape Leeuwin in May, from the north-westward, the current for five days was ten miles to the east; but at forty leagues from the cape, it ran N. 35 deg. E. fifteen miles; and from the meridian of the cape to past King George's Sound, the current set east, twenty-seven miles per day, nearly as it had before done in December. Captain Vancouver and admiral D'Entrecasteaux do not speak very explicitly as to the currents; but it may be gathered from both, that they also experienced a set to the eastward along this part of the South Coast.

The winds seem to blow pretty generally from the westward at Cape Leeuwin. In the summer time, they vary from north-west in the night, to south-west in the latter part of the day, though not regularly; and in the winter season this variation does not seem to take place. A long swell of the sea, called ground swell to distinguish it from the lesser, variable one of the surface, appears to come at all times from the south-westward, which indicates that the strongest and most durable winds blow from that quarter; and this was partly confirmed by our experience, for whenever it blew hard, the wind was at, or near to south-west.

It is from the superior strength and apparent prevalence of this wind, that the currents in the neighbourhood of Cape Leeuwin may be explained. The sea being driven in from the south-west, and meeting with the cape, will necessarily be divided by it, and form two currents, which will follow the directions of the land; one branch will run northward, along the west coast of Terra Australis, and the other eastward along the South Coast: our present business is to follow the latter current.

If a line be drawn from the south-western extremity of New Holland, to King's Island in Bass' Strait, it will show where the current may be expected to run strongest; though it will not be equally strong at those parts of the line which are distant from the land, as at those in its immediate vicinity. In drawing another line, from the north-eastern isles of the Archipelago of the Recherche to Cape Northumberland, we shall have what will commonly be the northern boundary of the current; for within this line the water does not seem to run in any constant direction, but is moved according as the wind may happen to blow. This was found by admiral D'Entrecasteaux; and is conformable to my experience, as I shall now explain.

It has been said, that the eastwardly current was found in May and December to run twenty-seven miles per day, from Cape Leeuwin past King George's Sound. From thence to a little beyond the Archipelago of the Recherche, keeping in with the shore, I found it to set north-east thirteen miles; and at a distance from the coast, it ran north-east-by-east sixteen miles per day, the wind being more from the south than from the northward in both cases.

In coasting from the Archipelago, all round the Great Bight and as far south-eastward as to Cape Northumberland, I had no determinate current; it generally followed the impulsion given to it by the winds, and was inconsiderable. From the middle of January to the middle of April, the winds were most prevalent from south-south-east to east-north-east; coming more from the land at night, and from the sea in the day time. They seldom had any strength; whereas the winds which occasionally blew from the westward were fresh, and sometimes became gales, veering in that case, invariably to the south-west.

On reaching Cape Northumberland I again found the eastwardly current; and from thence into Bass' Strait it ran N. 80 deg. E., at the rate of twelve miles a day, the wind blowing strong from the south-westward in the latter part of the time.

In a subsequent run across the Great Bight in May, from the Archipelago nearly direct for Bass' Strait, the current set upon the average, N. 39 deg. E. fourteen miles a day; appearing to be much influenced in its northern direction by the winds blowing strong from the southward. Mr. Dalrymple, in reasoning from the analogy of southern Africa, expected that the winds upon this coast would be found to blow from the northward, or off the shore, in the winter time, and this might possibly be the case if close in with the land; but at a distance from it, as just observed, the winds were from the southward.

Such an accumulation of water forcing itself through Bass' Strait, would naturally lead to the expectation of finding a strong current there, setting to the east; but on the contrary, the set in common cases was found to be rather in the opposite direction, the current appearing to be predominated by the tides, whose superior strength forced it below the surface. The flood comes from the eastward; and after making high water at Furneaux's Isles, passes on to Hunter's and King's Islands, where it meets another flood from the southward; and the high water then made seems to be nearly at the time that it is low water at Furneaux's Isles. Another flood is then coming from the east, and so on; whence a ship going eastward through the Strait, will have more tide meeting than setting after her, and be commonly astern of her reckoning. This applies more especially to the middle of the strait, and is what I there found with winds blowing across it; but the bight on the north side, between Cape Otway and Wilson's Promontory, seems to be an exception, and in fact, it lies out of the direct set of the tides. In running from Port Phillip to the Promontory I was set S. 73 deg. E., thirty-five miles in the day; but it then blew a gale from the west and south-westward.

Although the eastwardly current be not commonly found at the surface in Bass' Strait, it is not lost. Navigators find it running with considerable strength, when passing the strait two or three degrees to the east of Furneaux's Islands; and it was this current so found, which led admiral Hunter to the first opinion of the existence of an opening between New South Wales and Van Diemen's Land.

Every thing in Bass' Strait bespeaks the strongest winds to come from the south-west; and there is reason to believe that during nine months of the year, it generally blows from some point in the western quarter. In January, February, and March, eastern winds with fine weather seem to be not uncommon; but there is no dependence to be had on them at any other season. At the eastern side of the strait and of Van Diemen's Land, it is not unusual to meet a north-east or north wind, though it seldom blows strong. The gales usually come from between south-west and south-east, and most frequently from the latter direction; which renders it hazardous to approach the coast between Cape Howe and Wilson's Promontory.

Thus, speaking generally of the south coast of Terra Australis, it may be considered that during the six or eight winter months, the winds blow almost constantly from some western point; and that gales of wind at south-west are frequent. The progress of the gales is usually this: the barometer falls to 291/2 inches, or lower, and the wind rises from the north-westward with thick weather, and commonly with rain; it veers gradually to the west, increasing in strength, and the weather begins to clear up so soon as it has got to the southward of that point; at south-west the gale blows hardest, and the barometer rises; and by the time the wind gets to south or south-south-east, it becomes moderate, the weather is fine, and the barometer above 30 inches. Sometimes the wind may return back to west, or something northward, with a fall in the mercury, and diminish in strength, or die away; but the gale is not over, although a cessation of a day or two may take place. In some cases, the wind flies round suddenly from north-west to south-west; and the rainy, thick weather then continues a longer time.

Such is the usual course of the gales along the South Coast and in Bass' Strait; but on the east side of the strait the winds partake of the nature of those on the East Coast, where the gale often blows hardest between south and south-east. and is accompanied with thick weather, and frequently with heavy rain.

In the four or five summer months, the south-east and east winds appear to be most prevalent all round the Great Bight; but even there, the western winds sometimes blow at that time, and usually with considerable strength. Thus I had a strong south-west wind in the middle of February, near the Investigator's Group, and a gale from the same quarter in March, at the entrance of Spencer's Gulph; which last was felt still more severely in Bass' Strait by captain Baudin. At the two extremities of the coast, that is, in the strait and near King George's Sound, the winds blow sometimes from the west and sometimes from the eastward, in the summer; but the strongest winds are from the south-west.

It will hence appear, that the summer is alone the proper time for a ship to come upon, and still more so for exploring the south coast of Terra Australis; whether she proceed along it from west to east, as I did in the Investigator, or from east to west, as captain Baudin, seems to be almost a matter of indifference. From Cape Leeuwin to the end of the Archipelago of the Recherche, and from Cape Northumberland to Bass' Strait, it is perhaps most advantageous to proceed eastward, on account of the current; but in the intermediate and more considerable part of the coast, a western route is certainly preferable. It has also this general advantage, that the winds which are fair for running along the coast are those that blow moderately, and are accompanied with fine weather, most proper for making a survey; whereas those favourable to the opposite route frequently blow strong, and render it dangerous to keep in with the land. As to making a survey of the South Coast in the winter season, which had been judged from theoretical analogy to be the most proper time, it appears to be not only a dangerous experiment, but also one from which very little accuracy of investigation could be expected; and with as much ardour as most men for such pursuits, I should very unwillingly undertake the task.

[SOUTH COAST. SAILING DIRECTIONS.]

These observations upon the danger of sailing along the South Coast in the winter season, are not meant to apply to the commander of a ship desirous of going eastward through Bass' Strait, and of seeing no more of the land than is necessary to assure his situation. The strait may be passed without more than very common danger, at any time of the year, provided that the navigator be certain of his latitude before approaching the longitude of 1431/2 deg.; he should not, however, enter the strait in the night, unless he have previously seen the land, or be certain both of latitude and longitude. The parallel of 39 deg., or 39 deg. 20', according as the wind may incline, is the best for taking a ship between King's Island and Cape Otway; and a sight of either, or preferably of both, will point out his position on the chart. The sole danger to be apprehended here, is the Harbinger's Reefs, two patches lying nearly two leagues out from the north end of King's Island; but are so far separated from it, and from each other, as to leave practicable passages between them, where the shoalest water found by the Cumberland schooner was 9 fathoms.

(Atlas Plate VI.)

When the position of the ship at the entrance of the strait is ascertained, a course should be shaped for Curtis' Island, which will be visible ten or eleven leagues from the deck in fine weather; and as the distance is between forty and fifty leagues, and nothing lies in the way, a part of it may be run in the night, with a good look-out. I would afterwards pass on the south side of Kent's Groups, at not a greater distance from the largest than two leagues; and then steer east-north-east by compass, if nearly before the wind, or on either side of that course as the wind may incline; but taking care not to approach the northern Long Beach.

In case of meeting with a continuance of foul winds, the most convenient places in the strait for anchorage, when going eastward, are these:

1st. Under the north-west end of King's Island, near the New Year's Isles. Of this anchorage I know only, besides what is given in the chart, that the brig Harrington there rode out a gale from south-west, the heavy sea being broken off by the New Year's Isles; and the shelter from eastern winds must certainly be much more complete.

2nd. Port Phillip; anchoring just within the entrance, on the south side. When a fair wind comes, a ship can get out of the port by means of the strong tides.

3rd. Hunter's Isles, between Three-hummock and Barren Islands; taking care not to anchor too close to the weather shore, lest the wind change suddenly.

4th. The bight between Wilson's Promontory and Cape Liptrap, in case of necessity; but I would not recommend this place, it being very dangerous should the wind shift to south-west.

5th. Kent's large Group for brigs and lesser vessels; in one of the small sandy coves under the eastern island.

6th. Furneaux's Isles, between Clarke's and Preservation Islands. If the ship be not able to weather Clarke's Island, and pass out to the south-eastward when the fair wind comes, she may run through Armstrong's Channel, with a boat ahead and a good look-out.

This is all that it seems necessary to say for the information of a commander desirous of going eastward through Bass' Strait; and with the chart in the Atlas, (Plate VI.), it is all that a man of moderate experience and judgment will desire. I have not mentioned the entrance to the strait between King's Island and Hunter's Isles, thinking it not to be recommendable; both on account of Reid's Rocks, which lie in the passage, and whose position is not well ascertained, and also because I am not satisfied that Hunter's Isles are placed in the chart at their true distance from King's Island: the difference of longitude is from an approximation only; but the error, if any, cannot exceed eight or ten miles, and is in excess. However, with daylight and a good look-out, the strait may be safely entered by this pass, at any time that a ship can carry sail upon a wind. I entered this way in the Investigator, during the night; but what a ship on discovery may do is not to be given as an example to others, whose sole objects are expedition and safety. The outlet by the pass called Banks' Strait, between Furneaux's Islands and Cape Portland, is perfectly safe; but is out of the way for a ship bound to Port Jackson.

It has been observed that the winds are commonly favourable for making a passage to the westward, through Bass' Strait and along the South Coast, in the months of January, February, and March. I have no personal experience of such a passage, further than through the strait, though it has lately been made several times; but to those who may be desirous of doing the same, and are strangers to these parts, the following observations may be acceptable.

The first remark is, that the three months when this passage is most easy to be made, are precisely those in which it is unsafe, if not impracticable to go through Torres' Strait; and the second, that it will generally be of no avail for a ship to be in Bass' Strait before the middle of December, and if it be the middle of January it will be preferable.

Ships coming from Port Jackson, or anywhere from the north-eastward, may take a departure from Cape Howe in 37 deg. 301/2' south and 150 deg. 5' east; but from thence, they should not steer a course more westward than south-south-west by compass, until in latitude 39 deg. 30'; on account of the danger to be apprehended from south-east winds upon the Long Beach. Having reached 39 deg. 30' they should steer a true west course, or west-by-south by compass, leaving the Sisters, the craggy islet, and a rock, on the larbord hand. The eastern island of Kent's large Group, which lies in 39 deg. 30' south, 147 deg. 19' east, and may be seen ten, or perhaps twelve leagues from the deck in fine weather, will come in sight ahead; and in passing three or four miles on the south side, the small western group will be seen, and is to be passed in the same way; as are Curtis' peaked Isles, which will then be in sight. From Curtis' Isles to the north end of King's Island, the course is nearly true west, and distance about forty-two leagues, with nothing in the way; but it is better to steer five or six leagues to the north of King's Island, if the winds permit. Should they hang to the westward of north, the course may be safely directed for Three-hummock Island; passing afterwards to the north or south of King's Island, as the winds may be most favourable.

In the case of foul winds, which, if the weather be thick or rainy, may be expected to fix at south-west and blow strong, there are many places where a ship may anchor, to wait a change; but the following appear to be the most convenient.

1st. Hamilton's Road, at the east end of Preservation Island.

2nd. On the south side of the largest Swan Isle, for small vessels, or under Isle Waterhouse.

3rd. Port Dalrymple.

4th. Various places amongst Hunter's Isles.

5th. Sea-elephant Bay, on the east side of King's Island, where there is fresh water; or under the north-east end of that island, if the wind be from south-west.

6th. Western Port, under Phillip Island; anchoring so soon as the ship is sheltered. A fair wind for going onward through the strait, will take a ship out of this port.

7th. Port Phillip.

(Atlas Plate I.)

After clearing Bass' Strait, I think it most advisable to keep at not more than ten or twenty leagues off the coast, from Cape Otway to Kangaroo Island; as the wind may there be expected more favourable, and the contrary current less strong than in steering a straight course toward Cape Leeuwin. But should the wind rise from the north-westward, with thick weather and a descent more than usually rapid in the marine barometer, a stretch off shore should immediately be made, to prepare for a south-west gale. A look-out must be kept for an island lying to the west-south-west of Cape Northumberland; it was seen by Mr. Turnbull, commander of the Britannia, south whaler, but the weather being thick, its situation was not well ascertained. According to the best information I could procure, this island lies in 381/4 deg. south, and about 1391/2 deg. or 3/4 east longitude.

From Kangaroo Island, a straight course may be made for the southernmost part of the Archipelago of the Recherche; but should the winds come from the westward and not blow a gale, or be light and unsteady, I would steer more northward, nearer to the land, in the hope of having them more favourable. From the Archipelago to Cape Leeuwin it seems best to keep at a distance from the land, unless under the necessity of stopping in that neighbourhood; for the current runs strong near the shore, and with the advantage of an offing of twenty or thirty leagues, a ship may lie clear of the cape with a wind which might otherwise keep her beating for many days.

There appears to be no place of shelter against western gales, between Bass' Strait and Kangaroo Island; but there are then, besides various anchorages under that island, the bays and coves at the entrance of Spencer's Gulph; and further westward, Coffin's Bay, Petrel Bay in the island St. Francis, and Fowler's Bay near the head of the Great Bight. Afterwards come Goose-Island Bay, Thistle's Cove, and the lee of Observatory Island, all in the Archipelago of the Recherche; the cove cannot be entered in a gale, but when once secured in the south-west corner, a ship will be safe; the other two places afford very indifferent shelter from strong winds, and are indeed fit only for a temporary anchorage in moderate weather. Doubtful-Island Bay and King George's Sound afford complete shelter against western gales; but some little time would be lost in getting out of them, if a ship waited until an eastern wind set in. Some account of all these places will be found in the preceding pages of this volume; with the exception of Observatory Island, for which D'Entrecasteaux's voyage may be consulted.

APPENDIX.

Account of the observations by which the Longitudes of places on the south coast of Terra Australis have been settled.

The lunar distances and other observations taken in the Investigator's voyage having been ordered by the Commissioners of the Board of Longitude to be recalculated by a professed astronomer, with every degree of correctness which science has hitherto been able to point out as necessary, this delicate, but laborious task was assigned to Mr. John Crosley, formerly assistant at the Royal Observatory at Greenwich; a gentleman who formed part of the expedition as far as the Cape of Good Hope, but whose ill health had then made it necessary to relinquish the voyage and return to England. The data and results of all the observations will probably be made public, by order of the Commissioners; but in the mean time, for the satisfaction of the geographer, and more especially for that of the seaman, whose life and property may be connected with the accuracy of the charts., the results of the lunar distances observed upon each coast are added in the form of an Appendix to the volume wherein that coast is described. It is by these results that the time keepers have been regulated; and the longitudes used in the construction of the charts are taken from the time keepers.

To appreciate the degree of confidence to which these results may be entitled, it is necessary to know under what circumstances the observations were taken; also the method used in the calculations, and the corrections which have been applied beyond what is usual in the common practice at sea: of these the following is a general statement.

1st. The instruments used in taking the distances, were a nine-inch sextant by Ramsden, and three sextants of eight inches radius by Troughton, the latter being made in 1801, expressly for the voyage. On board the ship, the sextant was necessarily held in the hand, and the distances were sometimes so taken on shore; but in most of the latter cases, it was fixed on a stand admitting of the sextant being turned easily in any direction. The telescopes were of the largest magnifying powers which the motion of the ship, or state of the atmosphere could admit, and each longitude is the result of a set of observations, most generally consisting of six independent sights. They were taken either by lieutenant Flinders or by myself; those by him being designated in the column of Observers by the letter F, the others by C.

2nd. Preparatory to the reduction of the apparent to the true distance, the four following corrections have been applied.

From the sun's semi-diameter, as given in the nautical almanack, 3" have been subtracted. In the almanacks of the years comprehending our observations, the semi-diameter was stated from Mayer's tables, which gave it 3" too great; owing to the imperfection of the telescope with which Mayer observed.

The semi-diameters of the sun and moon being less in the vertical, than in the horizontal direction, on account of the differences in the refraction, they have been reduced proportionally to these differences and to the angles at the points of contact in measuring the distance. This correction is called contraction of the semi-diameter.

Before using the moon's horizontal parallax in the nautical almanack, where it is calculated for the equator, it has been corrected (printed as 'diminished', and corrected in the errata) by a number of seconds depending upon the latitude of the place, and upon this assumed position: that the earth is a regular spheroid, whose polar axis is to the equatorial axis, as 320 to 321. This, and the preceding correction are unnecessary, unless where great exactness may be required.

The refraction of the heavenly bodies given in the tables, being calculated for a mean height of 50 deg. of Fahrenheit's thermometer, and 29.6 inches of the barometer, it has been corrected for the difference between these means and what was the state of the atmosphere at the time of observation.

3rd. In reducing the apparent to the true distance, Mr. Crosley has used the method of Joseph Mendoza de Rios, Esq., F. R. S., given with his Nautical Tables, second edition, 1809; and the tables from which the corrections were taken and the computations made, are those of the same valuable work.

4th. The reduced distance, found as above, has been corrected to the spheroidal figure of the earth, according to the theory explained in the Philosophical Transactions of the Royal Society of 1797; and for doing which, rules are given by Mr. Mendoza with his Nautical Tables of 1801. This calculation is tedious, and the correction, more especially in low latitudes, too small to be necessary in common cases.

5th. In the nautical almanack the distances are given to every three hours, but the irregularities of the moon's motion being such as to cause some inequality in the different parts of this interval, the distance at the hour preceding, and at the hour following the time of observation, was found by interpolation from the two nearest given on each side; and having the distances at Greenwich for each hour, the observed distance can never fall more than half an hour from one of them; and the moon's inequalities do not then produce any sensible error in the corresponding time, as obtained from common proportion. The correction arising from this process is seldom so important as to be necessary in sea observations.

6th. The longitude deduced from a comparison of the true distance at observation with the hourly distances at Greenwich, is contained in the following tables under the head of Longitude from Nautical Almanack. But as it frequently happened, that the observation was not taken exactly in the place which it is intended to fix, this longitude is reduced to that place by the application of the difference shown by the time keepers to have existed between the two situations. In ascertaining this difference, the rates of going allowed to the time keepers are generally those found at the place which is to be fixed; whether applied to observations taken before arriving, or after quitting that place. This, however, could be done only at those stations where rates had been observed; at the intermediate points, where the result of lunar distances is given principally as an object of comparison with the time keepers, the rates allowed in the reduction are those found at the station previously quitted; but then the difference of longitude is corrected by the quantity consequent on the following supposition: that the time keepers altered their rates from those at the previous, to those at the following station, in a ratio augmenting in arithmetic progression. The difference of longitude, thus corrected when necessary, is given under the head of Reduction by time keepers; and the longitudes reduced by it to the place intended to be fixed, are taken to be of equal authority with those resulting from observations made in the place itself.

7th. But these longitudes, whether reduced to, or observed in, the place to be fixed, still require a correction which is of more importance than any of those before mentioned. The theories of the solar and lunar motions not having reached such a degree of perfection as to accord perfectly with actual observation at Greenwich, the distances calculated from those theories and given in the almanack become subject to some error; and consequently so do the longitudes deduced from them. The quantities of error in the computed places of the sun and moon, have been ascertained at Greenwich as often as those luminaries could be observed; and Mr. Pond, the astronomer royal, having permitted access for this purpose to the table of errors kept in the Observatory, Mr. Crosley has calculated the corresponding effects on the longitude, and proportioned them to the time when our observations were taken. The combined effect of the two errors forms a correction to the longitudes obtained from the sun and moon; but when the moon was observed with a star, then the moon's error alone gives the correction. But it has sometimes happened, that there were many days interval between the observations of the moon at Greenwich, and that the errors preceding and following are so extremely irregular, that no accuracy could be expected in reducing them by proportion; in these unfortunate cases, that part of the error belonging to the moon has been taken absolute, such as it was found on the day nearest to the time of observation; but the sun's error is always from proportion. These corrections, with the interval in the Greenwich observations of the moon, are given under their proper heads.

8th. The longitudes thus computed, reduced to the intended point, and corrected, are placed under each other; and the mean of the whole is taken to be the true longitude of that point, unless in certain cases where it is otherwise expressed. The mean is also given of the longitudes uncorrected for the errors of the sun and moon's places, that the reader may have an opportunity of comparing them; and some sea officers who boast of their having never been out more than 5', or at most 10', may deduce from the column of corrections in the different tables, that their lunar observations could not be entitled to so much confidence as they wish to suppose; since, allowing every degree of perfection to themselves and their instruments, they would probably be 12', and might be more than 30' wrong.

In the nautical almanacks for 1811 and 1815, the distances are computed from the new tables of Burg for the moon, and of Delambre for the sun; and it is to be hoped that the necessity of correcting for errors in the distances at Greenwich will have ceased, or be at least greatly diminished. Should the computed places of the sun and moon be happily found to agree with actual observation, and supposing that our results may be taken as the average of what practised observers with good instruments will usually obtain when circumstances are favourable, then lunar observations taken in 1814 and afterwards, may be entitled to confidence within the following limits:

From one set of distances, consisting of six independent sights, the error in longitude may be 30' on either side; but will probably not exceed 12'.

From six sets on one side of the moon, each set consisting as above, the error may be 20'; but not probably more than 8'.

Twelve sets of distances, of which six on each side of the moon, are not likely to err more than 10' from the truth; and may be expected to come within 5'.

The error in sixty sets, taken during three or four lunations, and one half on each side of the moon, will not, I think, be wrong more than 5'; and will most probably give the longitude exact to 1' or 2', This degree of accuracy is far beyond what the hopes of the first proposers of the lunar method ever extended, and even beyond what astronomers accustomed only to fixed observatories will be disposed to credit at this time; but in thinking it probable that sixty sets of lunar distances will come within 1' or 2' of the truth, when compared with correct tables, I conceive myself borne out by the following facts.

In Port Lincoln, I observed an eclipse of the sun with a refracting telescope of forty-six inches focus, and a power of about two hundred. It was recalculated by Mr. Crosley from Delambre's and Burckhardt's tables, the one made four and the other ten years afterwards. The longitude deduced from the beginning differed only 1' 31.5" from that at the end, and the mean of both only 1' 17" from thirty sets of lunar distances corrected for the errors of the tables.

The Spanish admiral D'Espinosa observed emersions of the first and second satellites of Jupiter in 1793, at Port Jackson, and also an eclipse of the sun which he recalculated by the tables of Burg. He deduces from thence the longitude of Sydney Cove to be 151 deg. 12' 45"; and from forty-four sets of lunar distances by lieutenant Flinders, it would be 151 deg. 11' 49" east.

At Port Louis in the Isle Mauritius, the Abbe de la Caille observed an eclipse of the sun, the transit of mercury over the sun's disk, and various occultations of Jupiter's satellites; M. d'Apres also observed several occultations; and this place should therefore be well determined. Its longitude in the Requisite Tables is 57 deg. 29' 15" east; and from twenty-seven sets of distances taken whilst a prisoner there, I made it, when corrected for the errors of the tables, 57 deg. 29' 57" east.

In appreciating the degrees of accuracy to which a small or larger number of lunar distances may be expected to give the longitude, I suppose the observer to be moderately well practised, his sextant or circle, and time keeper to be good, and his calculations to be carefully made; and it is also supposed, that the distances in the nautical almanack are perfectly correct. As, however, there may still be some errors, notwithstanding the science and the labour employed to obviate them, it cannot be too much recommended to sea officers to preserve all the data of their observations; more especially of such as may be used in fixing the longitudes of places but little, or imperfectly known. The observations may then be recalculated, if requisite; the corrections found to be necessary may be applied; and the observer may have the satisfaction of forwarding the progress of geography and navigation, after having contributed to the safety of the ship, and benefit of the particular service in which he may happen to have been engaged.

Table I. (Reference from Chapter III., "Longitude from thirty-one sets of distances of the sun east and west of the moon, of which the particulars are given in Table I. of the Appendix to this volume") LONGITUDE OF THE OBSERVATORY IN PRINCESS ROYAL HARBOUR, KING GEORGE'S SOUND

Table II. (Reference from Chapter III, "The longitude from sixteen sets of distances of the sun east and west of the moon, of which the individual results are given in Table II. of the Appendix to this volume") LONGITUDE OF THE SOUTH POINT OF LUCKY BAY, ARCHIPELAGO OF THE RECHERCHE

Table III. (Reference from Chapter V., "Longitude of the point, deduced from twenty-two sets of distances (see Table III of the Appendix to this volume)") LONGITUDE OF THE ANCHORAGE IN FOWLER'S BAY

Table IV. (Reference from Chapter VI., "The longitude, from thirty sets of distances of the sun and stars from the moon (see Table IV. of the Appendix to this volume)") LONGITUDE OF THE TENTS, AT THE HEAD OF PORT LINCOLN

Table V. (Reference from Chapter IX., "Point Nepean is in latitude 38 deg. 18' south. The longitude from twelve sets of distances taken by lieutenant Flinders in the port, and six others by me ten days before arriving, the particulars of which are given in Table V. of the Appendix to this volume") LONGITUDE OF POINT NEPEAN AT THE ENTRANCE OF PORT PHILLIP

Table VI. (Reference from Chapter X., "Longitude from forty-four sets of distances of the sun and moon, of which the individual results are given in Table VI of the Appendix to this volume") LONGITUDE OF CATTLE POINT, PORT JACKSON

Table VII. Variations in rate and errors in longitude, made by Earnshaw's time keepers No. 543 and No. 520, between the Cape of Good Hope and Port Jackson.



END OF VOLUME I