Returning to the junction of the two rivers, he followed down the united stream, and soon found himself involved in the same difficulties that had beset Kennedy. The river broke up into countless channels, running through barren, fissured plains. Toiling on over these, with an occasional interlude of sand hills, Gregory at last reached that portion of Cooper's Creek visited by Sturt. This he now followed down to where Strzelecki's Creek left the main stream and carried off some of the surplus flood water to the south. Gregory followed on the many channels trending west, but finally lost them amongst sand hills and flooded plains. He turned back and once more struck Strzelecki's Creek, which he thought he traced to Lake Torrens. This lake he crossed on a firm sandy space, through which he could distinguish no connecting channel, thus helping to rob Lake Torrens of some more of its terrors. He soon arrived in the settled districts, having safely accomplished a most successful journey. The main discovery that was the most valuable outcome of this trip was, of course, the confirmation of the supposed identity of the Barcoo and Cooper's Creek; as Gregory was otherwise on the tracks of former explorers, no fresh discoveries could well be expected on the course he followed. Thus, after many fruitless efforts and disappointments, the second great inland river system was evolved. We now meet with an old friend in the field, in the person of J. M'Dowall Stuart, formerly draughtsman for Captain Sturt, and one of the party who bought experience of heat, thirst, and desolation, during their long imprisonment in the depôt glen. On the 14th May, 1858, Stuart left Oratunga for an excursion to the north-west of Swinden's country, west of Lake Torrens. He was delayed some time before he finally got away from Octaina, on the 10th June. Passing Mr. Babbage, he arrived at the Elizabeth on the 18th, but was disappointed in the expectations he had formed. Soon afterwards he found a large hole of permanent water, which he called Andamoka, and on the 23rd June caught sight of one of the arms of Lake Torrens. From here he followed a creek (Yarraout) to the north-west, in search of the country called Wingillpin that the blacks had told him of. This he was unable to find, and came to the somewhat strange conclusion that Wingillpin and Cooper's Creek were one and the same, although so widely separated, as he well knew. He also seems to have entertained broad notions of the extent of Cooper's Creek, as in one part of his journal at this period he remarks:-- "My only hope now of cutting Cooper's Creek is on the other side of the range. The plain we crossed to-day resembles those of the Cooper, also the grasses. If it is not there it must run to the north-west, and form the Glenelg of Captain Grey."