A Voyage to Terra Australis Volume II Part 7

Towards Double Mount and Shoal-water Bay, the country consisted of gently-rising hills and extensive plains, well covered with wood and apparently fertile. The stream at the head of Broad Sound could not be traced from hence more than three or four miles above the tent; but it may possibly run up much further to the south-eastward, though too small to be distinguished in the wood, or to be navigable for boats. To the south and westward there was a ridge of high land, which appeared to be a prolongation of the same whence the upper branches of Port Bowen and Shoal-water Bay take their rise, and by which the low land and small arms on the west side of Broad Sound are bounded. A similar ridge ran behind Port Curtis and Keppel Bay, and it is not improbable that the two are connected, and of the same substance; for at Port Curtis the basis stone of the country was a granite, and this small hill was the same. It has been more than once observed, that granite is amongst the substances which exert an influence upon the magnetic needle; and it is to the attraction of the ridge of mountains to the south and westward, that I attribute the great variation found in the bearings at this station.

We returned to the tent at sunset; and there pa.s.sed a disagreeable night amongst musketoes, sand flies, and ants. At four in the morning [THURSDAY 16 SEPTEMBER 1802] the ebb had made, and we embarked in the boat; but the depth of water was so little that we could not proceed, and were obliged to re-land and wait for the following tide; not without apprehension of being left till the next springs came on. At two in the afternoon the flood came up rapidly, and in half an hour it was high water; we set off immediately, and after some trouble from the shoals, reached the brig at five o'clock. Mr. Murray got under way at three the next morning [FRIDAY 17 SEPTEMBER 1802] to beat down to Upper Head, the wind being from the northward; but the Lady Nelson getting aground, I went off with Mr. Brown in my boat, and reached the ship at seven o'clock, and in the evening, the brig arrived.

Lieutenant Fowler had gone through the most essential duties, and the ship was nearly ready for sea; but on landing at the tents I found that the time keepers had been let down, and the business of finding new rates for them was to be recommenced. This accident would require a week to be repaired; and being unwilling to remain so long inactive, I determined to leave Mr. Flinders at Upper Head, and take the ship over to the inner end of Thirsty Sound, where it appeared there was something to correct in captain Cook's chart.

SAt.u.r.dAY 18 SEPTEMBER 1802

The Lady Nelson had lost two sheets of copper, and the trunks of the sliding keels required some reparation; I therefore desired lieutenant Murray to lay his vessel on sh.o.r.e and get these matters arranged, to cut wood for himself, and be ready to sail in a week for Torres' Strait; and his stock of water was completed out of the Investigator.

SUNDAY 19 SEPTEMBER 1802

On the 19th in the morning we unmoored the ship, and a little before low tide stretched over towards Thirsty Sound; but the numerous shoals to be encountered, and which cannot be concisely described otherwise than in a chart, caused much delay; and it was near noon of the day following [MONDAY 20 SEPTEMBER 1802] before we anch.o.r.ed at the south end of Long Island, in 3 fathoms, and about one mile from the low mangrove sh.o.r.e. At the south end of the island was a small hill, bearing S. 55 E. one mile and a half from the ship, where I landed with a party of the gentlemen; it forms the west point of the inner entrance to Thirsty Sound, as some low red cliffs, one mile and a half distant, do the east point; but a shoal, dry at low water, lies in the middle, and the channels on each side are not calculated for a ship. The small hill was found to be on a detached islet one mile long, the greater part of which is mud covered with mangroves; the hill is partly excavated by an arched way running through it, and the stone is of a mixed red and white colour, and of an ochry consistence. From the highest top, I set:

Upper Head, bearing S. 28 22' W.

Double Mount. S. 53 20 E.

Pine Mount, S. 61 5 E.

These bearings place the inner end of Thirsty Sound in lat.i.tude 22 16'; and curtail the distance of thirty miles from Pier Head in captain Cook's chart, to twelve miles and a half.

TUESDAY 21 SEPTEMBER 1802

On the 21st, the botanical gentlemen went over in the launch to the east side of Thirsty Sound, the main land having been always found more productive in the objects of their pursuit, than any island however large. I went to examine along the west side of Long Island; but had not proceeded two miles before an opening presented itself amongst the mangroves. It led to the eastward, and then separated into two branches; and in following that which trended north-east I came into Thirsty Sound, and landed five miles above the inner entrance, at an islet in mid-channel, which had been set from Pier Head and is laid down by captain Cook.

No less than five different pieces of land were found to be cut off from the south end of Long Island, by winding channels amongst the mangroves; and I now saw the prospect of a pa.s.sage through the middle, leading out at the bight between the north point and Pier Head. A woody and rather elevated islet obscures the inner end of the opening, and seems to have prevented captain Cook's observing this separation when going up Thirsty Sound in his boat. I found in it a good bottom, with 3 to 5 fathoms water, and room for a ship to swing, or sail through as far as the outer opening to sea; but another island lies in the outlet, the bottom is rocky, and the regular depth at low water is not so much as 3 fathoms on either side.

Having taken a second set of angles, and pa.s.sed out by the new opening, I steered northward along the east side of Long Island; but although the land be high and rather steep, there was seldom so much as 3 fathoms at a mile distance. I landed at the north end of the island, to ascertain better the forms and positions of the North-point Isles; and then, steering southward along the west side, entered a cove where the form of the surrounding land gave a hope of finding fresh water for the ship; but the borders were covered with mangroves, and we could not get sufficiently far up to know whether any part of the stream running through them were fresh. Another set of angles was taken from a hill on the south side of the cove; and the sun being then set, our tent was pitched for the night.

WEDNESDAY 22 SEPTEMBER 1802

Next morning I steered onward along the west side of Long Island, landing occasionally to examine the gullies made by the rains; but at this time they were all dry. As far to the south as Westside Islet, the sh.o.r.e is tolerably high and the water deep; and near to the inner end of the islet, where I landed to take angles, there was no bottom with 10 fathoms; but the sh.o.r.e from thence to the ship was low and covered with mangroves, and even the rocky points cannot be approached within half a mile, except by boats.

Not a single Indian was seen during this excursion round Long Island; nor from the length of the gra.s.s and appearance of their fire places, do I think they had been there for some months.

THURSDAY 23 SEPTEMBER 1802

Next day I made a further examination of the winding channels at the south end of Long Island; and also went to an inlet on the east side of Broad Sound, the entrance of which is so much obstructed by shoals, that it was difficult to find a sufficient depth, even for the boat. I landed with the naturalist at a low, cliffy head on the north side of the entrance; but not without wading a quarter of a mile in the mud. We saw from thence, that this inlet, though presenting the appearance of a respectable river when the tide was in, had no perceptible breadth at five miles within the land, that it was almost wholly dry at low water, and that the sh.o.r.es were covered with mangroves to a great extent; even the cliffy head where we stood, was surrounded with mangroves, and appeared to be insulated at spring tides.

FRIDAY 24 SEPTEMBER 1802

In the morning of the 24th, we got under way to return to Upper Head; and having the same difficulties to encounter amongst the shoals as before, did not reach our former anchorage until next day [SAt.u.r.dAY 25 SEPTEMBER 1802]. On landing at the tents, I found, to my no less surprise than regret, that the time keepers had again been let down; and no more than one day's rates had been since obtained. Twenty-five sets of distances of the sun and moon had been taken to correspond with an equal number on the opposite side; and it appeared that lieutenant Flinders being intent upon these, had forgotten to wind up the time keepers on the 22nd at noon.

This fresh difficulty was very embarra.s.sing. To go away for Torres'

Strait and the Gulph of Carpentaria without good rates, was to cripple the accuracy of all our longitudes; and on the other hand, the expected approach of the contrary monsoon on the North Coast admitted of no longer delay in Broad Sound. On comparing the last day's rates with those of the four days previously obtained, the letting down did not appear to have produced any material alteration; and I therefore determined to combine the whole together, and to sail immediately.

SUNDAY 26 SEPTEMBER 1802

The following day was occupied in completing the holds with wood, taking on board our sh.o.r.e establishment, and preparing for sea; and next morning [MONDAY 27 SEPTEMBER 1802] we steered down Broad Sound, with the Lady Nelson in company, keeping near the western side to avoid the middle shoals. On a sea breeze coming in at north, we tacked towards the North-point Isles; and at sunset, the flood tide having then made, anch.o.r.ed in 8 fathoms, upon a bottom of sand and rock, the north-westernmost isle bearing N. 6 E., two leagues. In the morning we pa.s.sed round the North-point Isles, with a breeze from the south-east; and thus quitted Broad Sound, steering off for the outermost and largest of the Northumberland Islands.

There remains little to be said upon the navigation of Broad Sound, more than what has been related of our courses in it, and what will be found in the chart. The western channel, between the Flat Isles and the main, is not to be recommended; but after steering up the middle of the Sound and pa.s.sing these isles, the western sh.o.r.e should be kept nearest a-bord.

A ship may then reach Upper Head without difficulty, and lie there in perfect safety from all winds, at two-thirds of a mile off; but cannot go higher up the sound without risk of grounding on the banks. From half flood to half ebb, landing is easy at Upper Head, and it is perhaps the sole place on the main possessing that advantage; every where else the sh.o.r.e is very low, fronted with mud banks, and covered, in some places miles deep, with interwoven mangroves, amongst which the tide flows at high water.

The stone of Upper Head, and apparently of all the hills in its neighbourhood, is granitic; whilst that of Long Island and West Hill approach nearer to porphyry. At the inner entrance of Thirsty Sound the points are mostly composed of an earth, which is not heavy, is sometimes red, but more frequently white, or mixed; and of a consistence not harder than ochre.

Long Island, though covered with gra.s.s and wood, is stony and incapable of ordinary cultivation. On the main land, the low parts between the mangroves and the hills seemed to be of a tolerably good soil; and according to the report of some of the gentlemen, who made an excursion at the back of Upper Head, the vallies there produce good gra.s.s and appeared fertile. There seems, indeed, to be a considerable extent of land about Broad Sound and on the peninsula between it and Shoal-water Bay, which, if not calculated to give a rich return to the cultivator of wheat, would support much cattle, and produce maize, sugar, and tobacco; and cotton and coffee would grow upon the more rocky sides of the hills, and probably even upon Long Island. Should it ever be in contemplation to make an establishment in New South Wales within the tropic, in aid of Port Jackson and the colonies to the southward, this neighbourhood would probably be chosen; and the great rise of tide presents advantages which might be some time turned to account in ship building. On the west side of the sound, near the Flat Isles, the rise at spring tides is not less than thirty, and perhaps reaches to thirty-five feet. At Upper Head it is from twenty at the neaps, to thirty or more at the springs; but the bottom rises so much towards the top of the sound, that the tide there never seems to exceed twelve feet. The time of high water is nearly _eleven hours after_ the moon's pa.s.sage over and under the meridian; though the flood runs up near an hour on the west side of the sound, after it is high water by the sh.o.r.e.

The places best calculated for the construction of docks, appear to be at the uppermost or 4th Flat Isles, where the shoals form a natural harbour, and at the entrance of the opening near Upper Head, in which is a small islet of sand and rock, not covered with mangroves nor surrounded with mud flats. The pines of Port Bowen, Shoal-water Bay, and the Northumberland Isles, would furnish the necessary spars and lighter planking; and there is no reason to think that the _eucalyptus_, which grows all over the country, should not be as fit for timbers, etc., as it is found to be further southward. No iron ore was seen in the neighbourhood; but were a colony established and the back ridge of mountains well examined, this and other metallic productions might be found. The attraction which the mountains seemed to have upon the needle, is in favour of this probability; but the iron work might be prepared at Port Jackson where the ore exists, and in whose vicinity there are plenty of coals.

Fresh water was scarce at this time, none being any where discovered near the sea side, except a small rill at the back of Upper Head, little more than adequate to the supply of the tents; it can however be scarcely doubted, that fresh water for domestic purposes would be found in most parts of the country; and there is a season of the year, most probably the height of summer, when rain falls abundantly, as was demonstrated by the torrent-worn marks down the sides of the hills.

Not a single native was seen, either on the sh.o.r.es of Thirsty, or Broad Sounds, during the whole time of our stay.

There are kangaroos in the woods, but not in numbers. The shoals all over the sound are frequented by flocks of ducks and curlews; and we saw in the upper part, some pelicans, an individual of a large kind of crane, and another of a white bird, in form resembling a curlew. Many turtle were seen in the water about Long Island, and from the bones scattered around the deserted fire places, this animal seemed to form the princ.i.p.al subsistence of the natives; but we had not the address to obtain any.

Hump-backed whales frequent the entrance of the sound, and would present an object of interest to a colony. In fishing, we had little success with hook and line; and the nature of the sh.o.r.es did not admit of hauling the seine.

The climate here, being one degree within the tropic, was warm at this season, which may be considered as the spring and the driest time of the year. On board the ship, the height of the thermometer did not exceed 76, with the warm winds from the northward, but at the tents it averaged at noon somewhat above 90; and the musketoes and sand flies were very troublesome at all places near the mangroves. We did not see any snakes or other venemous reptiles or insects.

The _lat.i.tude_ of Upper Head, from six meridian observations in the artificial horizon, is 22 23' 24" S.

_Longitude_ from fifty sets of distances of the sun and moon, given in Table II of the second Appendix to this Volume, 149 46' 53" E.

The errors of the time keepers from mean Greenwich time, at noon there Sept. 26, and their mean rates of going during seven days, of which four were before and three after they had been let down the second time, were as under:

Earnshaw's No. 543 slow 2h 3' 37.23" and losing 9.62" per day.

Earnshaw's No. 520 slow 3h 29' 15.57" and losing 21.41" per day.

These errors and rates were found by lieutenant Flinders, from equal alt.i.tudes taken with a s.e.xtant on a stand, and using an artificial horizon of quicksilver.

The longitudes given by the time keepers on Sept. 12 a.m. at Upper Head, with the Port-Jackson rates, were these:

No. 543, 149 54' 27" east.

No. 520, 149 53' 47.5" east.

The mean is 7' 14" to the east of the lunars; but on using rates equally accelerated from those at Port Jackson to the above at Upper Head, and commencing the acceleration on Aug. 15, at Keppel Bay, where the time keepers were found to be keeping their former rates, the mean longitude will be 149 48' 56.6", or 2' 3.6" from the lunar observations; which is therefore the presumable sum of their irregularities after August 15, or in 27.7 days.

In fixing the positions of places along the East Coast, I have made use of the time keepers from Port Jackson to Port Curtis, without any correction. From Port Curtis to Broad Sound, the coast and islands are laid down from theodolite bearings taken on sh.o.r.e, combined with the observed lat.i.tudes; and consequently the accuracy in longitude of the first portion depends upon that of Port Jackson and the time keepers, and of the last, upon Upper Head and the survey. These two unconnected longitudes meet at Port Curtis, and the difference between them is there no more than 5".

From observations with the theodolite upon the top of Upper Head, the _variation_ was 8 37' east; but on moving the instrument ten yards to the south-west, it was 45' less. At two other stations on the west side of the sound, it was 8 15', and 8 0'; and on board the ship 7 17' and 7 46', corrected. On the east side of the sound it differed at six stations on sh.o.r.e, from 8 to 6; and on board the ship was 6 44'

corrected. As general results, therefore, but subject to many small deviations, the variation may be taken,

On the west side of Broad Sound at 8 0' E.

On the east side 7 0 At the head of the sound it was, at one station 12, at another 10; the mean, 11 0

The differences between the two sides of the sound, both on sh.o.r.e and on board, are nearly similar to what took place in Shoal-water Bay.