According to arrangements made with Captain King and Mr. Dunlop, the King's astronomer at the Parramatta observatory, I halted the party this day in order to make hourly observations of the barometer, thermometer, the sky, etc. This plan had been strongly recommended by Sir John Herschel; and for our present purposes it was most desirable in order that we might ascertain how far the fluctuations of the atmosphere in two places so distant as Parramatta and Byrne's creek corresponded in these simultaneous observations. During our last journey some discrepancies in the heights determined by the barometer on the Darling led to a suspicion that the fluctuations at such great distances, in situations so dissimilar, might vary considerably; and this was now to be ascertained. THE PARTY IMPEDED BY ROCKS. March 22. We continued our journey along the left bank of the creek, but with considerable difficulty and delay occasioned by the projection of the rocky escarpment of the above-mentioned extremities of Mount Marga; so that we had to break away masses of rock and move the carts one by one, all hands assisting. We at length gained a pleasant tract of land on which the grass was green and luxuriant in consequence of some partial rain; and on this place I encamped with the intention of next day ascending Marga. In the creek we found ponds, deep and clear like canals; their borders being reedy and their margins green. In these ponds the natives speared several fishes which had however a muddy flavour. Among them was one, apparently the eel-fish, caught during my first expedition in the Namoi and upper Darling.* This circumstance was rather in favour of the supposition that the streams unite; but still the fish seemed somewhat different. (*Footnote. Plotosus tandanus see Volume 1.) SNAKES. On this day's journey we saw several large snakes; one, large and black, was shot while swimming in a pond in the creek; the others were of that kind named, from the beautifully variegated skin, the carpet snake. The natives considered the latter very fierce and dangerous, saying it never ran away but always faced or pursued them. It had in fact the flat broad head and narrow neck which in general characterise the most venomous snakes, also large fangs hooked inwards, which the natives particularly pointed out. It had also, near the tail, two articulations with something like a toe and joint on each, such as I had not observed before in any other kind of snake. A smaller one of the same kind attacked one of the party, and also a native, but the former shook it from his clothes, it then fixed its teeth in the skin of the native who detached it with difficulty; but as no blood came from the bite he seemed to care little about it. The native name of this place was Cuenbla. VIEW FROM MARGA. March 23.