“Depot, near Mount Arden,
July 22nd, 1840.

“Sir,—­I have the honour to acquaint you for the information of His Excellency the Governor, and of the colonists interested in the northern expedition, with the progress made up to the present date.

“I arrived here with my party all well, on the 3rd July instant, and on the 6th I proceeded, accompanied by one of my native boys, on horseback, to reconnoitre Lake Torrens and the country to the north of the depot, leaving the party in camp to rest the horses and enable the overseer to get up, from the head of Spencer’s Gulf, the supplies kindly sent by His Excellency the Governor in the Waterwitch—­her arrival having been signalised the evening previous to my leaving.  I arrived on the shores of Lake Torrens the third day after leaving the depot, and have ascertained that it is a basin of considerable magnitude, extending certainly over a space varying in width from 15 to 20 miles, and with a length of from 40 to 50, from its southern extremity, to the most northerly part of it, visible from a high summit in Flinders range, (about ninety miles north of Mount Arden).  The lake is girded with an outer ridge of sand, covered with salsolaceous plants, and with saline crusts, shewing above the ground at intervals.  Its waters appear to extend over a considerable surface, but they are, seemingly, shallow.  I could not approach the water, from the soft nature of that part of its bed, which is uncovered, and which appeared to reach from three to four miles from the outer bank to the water’s edge.  There can be no doubt, however, of its being very salt, as that portion of its bed which lay exposed to our view was thickly coated with pungent particles of salt.  There were not any trees or shrubs of any kind near the lake where we made it, nor could either grass or fresh water be procured for our horses.  Lake Torrens is bounded on its western side by high lands—­apparently a continuation of the table land to the westward of the head of Spencer’s Gulf.—­I should think that it must receive a considerable drainage from that quarter, as well as the whole of the waters falling from Flinders range to the eastward.

“From the very inhospitable nature of the country, around the lake, I could not examine it so carefully or so extensively as I could have wished.  My time, too, being very limited, made me hurry away to the northward, to search for a place to which I might bring on my party, as the grass in the neighbourhood of the depot was very old, and much less abundant than on either of my former visits there.  It became, therefore, imperative on me to remove the horses as speedily as possible.  Should circumstances permit, I shall, however, endeavour to visit Lake Torrens again, on my return from the northern interior.  After leaving the lake I spent many days in examining the country to the northward of our depot.  Its character seemed to vary but little; barren sandy plains