On the 23rd of June they came on a large western-flowing river, which he called the Ashburton, and which has since proved to be the longest river in Western Australia.  Having crossed this river, and still pursuing a southerly course, he arrived at a sandstone tableland, and on the 23rd had, as Gregory writes, “at last the satisfaction of observing the bold outlines of Mount Augustus.”

He returned to the depot camp on the 29th, and though anxious to follow up the Ashburton to the east, the condition of his horses’ feet and the lack of shoes prevented him.  During the return journey to Nickol Bay, he ascended Mount Samson, and from the summit obtained an extensive view that embraced every prominent peak within seventy miles, including Mount Bruce to the north, and Mount Augustus to the south, the distance between these two elevations being 124 geographical miles.  They crossed the Hammersley Range on to the level plains of the Fortescue by means of a far easier pass than that used on the outward journey, and arrived at the Bay on the 19th of July.

On the 31st of July Gregory started on a new expedition to the east.  On the 9th of August he came to a river which apparently headed from the direction they desired to explore —­ namely the south-east.  Crossing another river, which they named the Shaw, the explorers, still keeping east and south of east, found on the 27th of August, a river of some importance running through a large extent of good pastoral and agricultural land.  This river was named the De Grey, but as their present object was to push to the south-east, they left its promising banks and proceeded into a hilly country where they soon became involved in deep ravines.  After surmounting a rugged tableland, they camped that night at some springs.

The next night, the 29th of August, they came, some time after dark, on to the bank of a wide river lined with the magnificent weeping tea-trees.  As three of the horses were tired out, Gregory determined to follow this river up for a day or two, instead of closing with a range of granite hills, capped with horizontal sandstones, which loomed threateningly in their path.

So for two or three days they continued on the Oakover, as he christened the river, and followed its western branch; a tributary of that led them in amongst the ranges, which were threaded by an easy pass.  On the 2nd of September they got through the ranges and emerged upon open sandy plains of great extent, with nothing visible across the vast expanse but low ridges of red drift-sand.  Here it was Gregory’s lot to experience a test almost equal to one of the grim tramps that had tried Sturt and Eyre.

He camped at a native deserted camp, and the next day failing to find any water ahead, had to return and form a depot.  Here he left five of the party with instructions to remain three days and then fall back upon the Oakover.  He himself, with Brown and Harding, and six horses, went on to find a passage.