Journals of Australian Explorations

by Augustus Charles Gregory; Francis Thomas Gregory

MAGNETIC ROCKS RENDER THE COMPASS USELESS.

24th September.

As it was very important that I should obtain a round of bearings before proceeding any further, the country having for some days past been too flat to afford many opportunities for triangulation. I to-day started with Messrs. Harding and Brown to ascend the ranges that lie to the west of the river. A scramble of three miles over very rugged rocks brought us to the highest point, which was found to be not more than 500 feet above the sea; our journey, however, turned out to be fruitless, the magnetic attraction of the volcanic rocks of which the hills are composed being so great as to reverse the needle, which varied so much that I could not even make use of the compass to take angles, and I had omitted to bring a sextant. Kangaroos were numerous among these hills, but we did not succeed in shooting any; they appear to be similar to those seen on the plains near the Sherlock. The view we had of the country was very extensive. To the south is a vast gently-undulating plain, only occasionally interrupted by detached granite and sandstone peaks; while narrow green lines of trees intersecting the plain in various directions indicate the watercourses coming from the distant ranges, and wander in wide sandy channels towards the sea; the course of the Strelley being easily distinguished for many miles. To the north the eye could trace the broad sandy bed of the DeGrey, trending towards Breaker Inlet, the position of which was only distinguishable by the margin of deep-blue mangroves that line it, and the whole of the extremity of the delta formed by the alluvial deposits brought down by the river. To the east and west of this is a wide expanse of alluvial flats, covered in most parts with rich, waving grass, the sameness of the scenery being relieved by detached patches of open park-like forest of flooded-gum. Returning to the camp by noon, the remainder of the day was devoted by me to bringing up the arrears of mapping, etc., and by the party generally in providing a supply of fish and ducks, which here were found to be very plentiful.

25th September.

By 7 a.m. we were once more tracing down the DeGrey through the flats seen yesterday. At eight miles the river divided into two channels of nearly equal width, the eastern one being followed to latitude 20 degrees 5 minutes 16 seconds, travelling being very heavy, on account of the numerous rat-holes that completely undermine the banks of the river for more than a quarter of a mile back on either side. For the last few miles the water in the river was decidedly brackish, and at our camp was evidently influenced by the tides; we, however, procured some tolerably good water by sinking a well in a sandbank in the dry portion of the channel, which here was about 300 yards wide. Camp 90.

SUDDEN RISE OF TIDE.

26th September.

This morning we found the water in the well quite salt, in consequence of the tide having risen during the night; and as our horses required water, it was found desirable to fall back upon some of the fresh pools to form a camp, while a day or two could be devoted to the examination of this fertile and interesting tract of country. We accordingly crossed the channel and proceeded westward for nearly three miles, when we came upon the other branch, which proved eventually to join again several miles below, forming an island containing some 8000 or 9000 acres of alluvial flat soil, covered with a quantity of mixed grasses. To this was given the name of Ripon Island. The western channel was found to be over 300 yards wide, and to contain several fine reaches of open water, some fresh and others slightly brackish; they were all teeming with ducks and a great variety of water-fowl. Having selected a suitable spot for a camp, I started with Messrs. Brown and Harding to examine the country towards the inlet. At a little more than two miles we crossed the river between two pools of salt water, subject to the influence of the tides, and proceeded northward over an open grassy flat for two miles further, when the grass gave place to samphire and small mangrove bushes, which gradually thickened to dense mangroves, cut up by deep muddy creeks, which put a stop to proceeding further in that direction. Here we observed several remarkable stacks of dead mangroves, evidently piled together by the natives, but for what purpose we could not ascertain, unless to escape upon from the tide when fishing. Having gained firm ground, we made a detour more to the eastward, and at last succeeded in reaching the bank of the river close to the head of the inlet. The tide being at the ebb, I was able to walk over the mud and sand to the mouth of the river, and obtain bearings to Points Larrey and Poissonier, and observe the character of the entrance, from which I formed the opinion that the breakers seen by Captain Stokes when surveying this portion of the coast, and which deterred him from entering the inlet, were nothing more than the sea-rollers meeting a strong ebb tide setting out of the DeGrey, possibly backed up by freshes from the interior which would, from a river of this size, occasion a considerable commotion where the tide amounts to twenty feet; at any rate, I could not observe any rocks, and there appeared to be a channel with at least five or six feet of water in it at low tide. For the first mile the river has a breadth of from 400 to 800 yards, and would admit with the tide vessels of twelve or fourteen feet draft of water with perfect safety up as far as Ripon Island, where they could lie completely sheltered in all weathers quite close to the shore, which here has steep banks twenty to thirty feet high; they would however, be left aground at low water, as we did not observe any pools in this part of the river. I had only just time to complete my observations when the roaring of the incoming tide warned me that no time was to be lost in returning to the horses, which were nearly a mile higher up the river. Although I ran part of the way, the mud creeks filled up so rapidly, there was some risk of my being cut off from the shore and having to take up a roost on the top of the mangroves until the tide fell; I had time, however, to observe that the head of the tide carried with it thousands of fish of great variety, amongst them a very remarkable one from three to six inches in length, in form resembling a mullet, but with fins like a flying-fish; it is amphibious, landing on the mud and running with the speed of a lizard, and when frightened can jump five or six feet at a bound; I did not, however, succeed in capturing one for a specimen. Swarms of beautiful bright-crimson crabs, about two inches diameter, were to be seen issuing from their holes to welcome the coming flood, on which was borne a great number of sea-fowl, who, it was evident, came in for an abundant feast in the general turmoil. Mounting our horses, that had stood for the last two hours without touching a mouthful of the rank grass around them for want of water, we returned to the camp by a different route, through open grass flats bordering the deep reaches of water that encompass the north-west side of Ripon Island.

SCARCITY OF WATER NEAR THE WEST.

27th September.