They reported having had an encounter with the natives on the 16th, and having been followed by a number of armed natives for a long way. Finally they had been compelled to fire on them, but had not killed any. They were glad to hear of the spring found, and, continuing on, reached it about half-past 6 o'clock. The spring is Fort Mueller of Mr. Giles, where he was camped for a long while, and his most westerly permanent water. By observation Fort Mueller is in latitude 26 degrees 11 minutes 30 seconds South, and longitude by lunar observation 128 degrees East, the variation being about 1 degree 25 minutes East by azimuths. 18th. Rested at spring. Marked a tree sixty yards south of camp F 74, being 74th camp from Geraldton. Also erected a pile of stones on peak, thirty chains West-South-West of camp, with a pole in centre, on which is marked: J. FORREST, AUGUST 17, '74. Took four sets of lunars, which place spring in longitude 128 degrees East of Greenwich. 19th. Steering East-South-East along Mr. Gosse's track for about thirty-five miles, over most miserable sandy hills and plains of spinifex, with the exception of a few miles at first, along a grassy flat. Two rock holes passed were quite dry. Camped without water on a grassy flat not far from the ranges; hope to find water early to-morrow, as our horses are too poor to go long without it. Was obliged to abandon police-horse Brick to-day, as he was completely done up. Nothing but downright poverty is the cause of his giving in; and the same in the case of Fame and Little Padbury, which we abandoned over a month ago. They were poor when they left, and have only had very dry grass ever since. It is a wonder to me they all do not give in, as many are mere skeletons. Poor old Brick held up as long as he could, but was forced to give in, and we had to leave him to his solitary fate; he will probably go back to the spring (Fort Mueller). Barometer 28.30; latitude 26 degrees 22 minutes 30 seconds South. 20th. Got a very early start, and continued on. At one mile found a sandy soak in a gully, and by digging it out got sufficient water for all our horses. Still proceeding onwards, following a gully for two miles, came to Mr. Gosse's depot Number 13, at Skirmish Hill. A bullock had been killed here, and the flesh jerked. Found a large white gum-tree marked GOS. 13 at camp. All the water was gone. I, however, camped, and took our horses to a place a mile west, where, by digging in the sand, we got enough for them. Went with Pierre to the summit of Skirmish Hill, and took angles. To the south, nothing but sand-hills and spinifex; to the North-East the Tomkinson Ranges showed up and looked very remarkable and promising. Marked a tree F 76, being 76th camp from Geraldton. Camp is in latitude 26 degrees 23 minutes 28 seconds, longitude about 128 degrees 32 minutes East. TOMKINSON RANGES.