Mean lat. 33 deg. 04 min. 02 sec. S.
Comp. long. 146 31 50 E.
Variation 7 23 00 E.
The series of triangles by which the longitude from our situation on the 17th of May has been computed, corresponds precisely with the bearings taken from this station to the principal objects forming their bases, and whose relative situation on the chart had been fixed on the 17th of May; it was extremely satisfactory to find in so extensive a survey that the angles should thus so completely verify our situation.
Our raft was finished and launched by one o'clock; its capability of carrying any burden we had to put upon it fully answered our expectations; but here its utility ended, the violence of the current caused by the high flood or the stream rendered all our labour abortive, as no exertions we were capable of making could enable us to get it across the stream. We had stretched a line across the river by which to tow it over, but the men were not able to withstand the force of the current acting on the body of the raft; they let go their line and were carried about three quarters of a mile down, when they were brought up by some trees and got safe on shore, making the raft fast. The flood had been slowly subsiding all day, giving us hopes that we should still be enabled to fell some trees for a bridge, which was now our only resource, as it was considered most advisable to use our utmost efforts to cross here rather than go farther up the stream.
August 2.—Cloudy weather with heavy rain during the night, which still continues. We commenced felling some trees, which we were in hopes would answer our purpose, our anxiety to cross being very great; as it is probable, from the long continued fine weather we have experienced until lately, that the rainy season in this part of the country may shortly set in, which would extremely embarrass and distress us.
We were again disappointed in our hopes of crossing by means of trees, as the flood which still continued swept them away as soon as felled. I sent Byrne up the stream to endeavour to find a better Place; but he returned in the afternoon without any success: he reported that about three or four miles above the tent a branch joined the stream, that he had travelled up it six or seven miles, but not far enough to say where it quitted the main stream; the low plains were several inches under water from the present rain; and the ground that appeared the driest was the worst to travel on, being a wet, loose, sandy bog. As the flood continued rapidly to subside, we resolved upon again trying the raft to-morrow morning; all hands were accordingly sent to tow her up, which was accomplished by night.
August 3.—A bleak cold morning, with continued small rain. At day-light we set to work with our raft: and after many trials had the satisfaction to find that we should succeed in getting over our baggage. Whilst Mr. Evans superintended this work, I rode up the river with Byrne to see the branch: I found it but an inconsiderable one, being merely a lagoon, except in times of flood like the present, when it appears nearly as large as the parent stream; it forms an island ten or twelve miles long, and from two to four broad. The impossibility of our travelling up this side was demonstrated, as well as the nature of these lower grounds or clear plains, which retain all the water that falls upon them, the little inequalities forming shallow pools. It was much better travelling over them, than on a low ridge of hills a couple of miles from the river on which I returned; the soil of the latter being so loose and boggy as to render it difficult for the horses to proceed.
On my return I found considerable progress had been made in transporting our luggage, and by four o'clock every thing was safely crossed; our little bark was however completely water logged, and at last would scarcely support a single man, though when first launched, three or four might venture in her with safety.
As I think the state of the seasons in New South Wales may serve to explain, at least partially, why there are no running streams in the western parts of it, it may be worth while to make some little inquiry into that subject. It appears to me that it can never rain simultaneously westward of the Blue Mountains and on the coast, for these reasons: first, That the Lachlan and Macquarie Rivers, being the sole channels by which the waters falling on the Blue Mountain range are conveyed westward to the low-lands, are always flooded in times of great rains in those mountains and on the coast; secondly, that the winter, that is to say, the period between March and August, is the time when the rains are most to be expected, and have most generally fallen on the east coast, and which so falling would naturally cause a flood in the streams above mentioned; thirdly, that in the summer season, or from September to February, which is certainly the driest period of the year, the rains fall westward of the Blue Mountains; but falling upon flat sandy land without any watercourses, do not in the smallest degree add to the waters of the Lachlan or Macquarie, which are then consequently in a state nearly if not entirely stagnant. It is at this season, therefore, that these streams are visited by the natives, as they are then enabled to procure the shell and other fish which abound in them. The tracks and impressions made by the feet of the natives were certainly made when the ground was very soft and marshy, whilst their guneahs were merely the branches of trees, and erected in places which we found to be swamps, but which in summer would, in comparison with the plains, be dry ground, the waters from them being drained off into the river.
The Blue Mountain range is by far the highest in New South Wales; the ranges westerly, though high when viewed from the low grounds from which they rise, cannot in any respect be compared with them.
In the summer, the north-east and south-east winds coming from the sea are forced over these mountains, and the vapours with which they are charged are attracted by the lower ranges westerly, and converted into rain. In the winter, the prevailing winds on the coast and inland, as is evident from the trees on the tops of the hills, are from south-west to north-west. In the winter, these westerly winds blowing over a vast extent of country, and coming with great violence on the Blue Mountains, confine those clouds and vapours which would occasion rain, to the vicinity of the coast, and the eastern side of the mountains. A wet summer on the east coast would occasion a flood in the Lachlan at that season; and should the rains then be attended with easterly winds, causing rain on the western side also, the whole low country must be under water for a double reason. This is a circumstance which, I think, could seldom happen, otherwise the consequence to the miserable natives must be dreadful.