On the 29th of May they struck the river which was subsequently named the Fortescue. As this river seemed likely to answer their expectations of a passage through the broken range that hemmed them in to the south, they followed it up. A narrow precipitous gorge forced them to leave the river, and, after surmounting a table-land, they steered a course due south to a high range, which, however, they found too rough to surmount. Making back on to a north-east course, they again struck the Fortescue, above the narrow glen which had stopped them. They followed it up once more through good country, occasionally hampered by its course lying between rugged hills; but they finally crossed the range, partly by the aid of the river-bed, and partly through a gap. On the 18th June, they succeeded in completely surmounting the range, and found that to the south the decline was more gradual. The range was named the Hammersley Range. Their horses had suffered considerably, and had lost some of their shoes in the rough hills. From here they kept south meaning to strike the Lyons River, discovered by Frank Gregory during his last trip. On coming to a small tributary which he named the Hardey, he formed a depot camp. Leaving some of the party and the most sore-footed of the horses, he pushed on with three men, Brown, Harding, and Brockman, taking three packhorses and provisions for eight days. 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.