On the North and East side of the outcrop the ground suddenly drops, forming what appears from the distance as a line of sheer cliffs.  Down this steep slope, which is covered with scrub, we discovered a passage, and, at the foot, found ourselves in an open spinifex plain with a sand-ridge on either hand.  We were steering N.E. by N., and in consequence had now and again to cross a ridge, since they ran due North-East.  After three miles low outcrops of limestone appeared at intervals, the scrub in the trough of the ridges became more open with an undergrowth of coarse grass, buck-bush or “Roly-Poly” (SALSOLA Kali) and low acacia.  Hugging the ridge on our left, we followed along this belt for another one and a half miles; when, close to the foot of a sandhill, our guide, secured to my belt by a rope round his waist, stopped and excitedly pointed out what seemed on first sight to be three rock-holes, in a small, bare patch of limestone not more than thirty feet across.  Twenty yards to the right or left and we would never have seen it; and to this spot King Billy had brought us full speed, only stopping once to examine some rocks at the foot of one ridge, as if to make sure that we were in the right valley.  On further investigation the three holes turned out to be entrances, of which two were large enough for a man to pass through, leading perpendicularly to a cave beneath.  With the help of a rope Charlie and I descended twenty-five feet to the floor of the chamber, which we found to be covered with sand to a depth of two feet.  In the sand we dug holes but did not succeed in getting even moisture.  Plunged as we were so suddenly into darkness, our eyes could distinguish no passage leading from the chamber, and it seemed as if we had been tricked again.  Further exploration by the light of candles revealed two passages, one leading west and upwards, the other east and downwards.  Charlie chose the latter; before long I came to the end of mine, having failed to find anything but bats, bones of birds and dingoes, and old native camp-fires.  Following Charlie, I found him crawling on hands and knees down a steep slope—­progress was slow, as the floor was rough and the ceiling jagged; presently the passage dropped again, and at the end, below us, we could see our candles reflected, and knew that at last we had water!  Who, except those who have had similar experiences, can picture one’s feelings of relief!  “Thank God! thank God!” is all one can reiterate in one’s mind over and over again.  The visible supply of water was small, and we had grave doubts as to any soakage existing!  Not wasting valuable time in discussion, we crawled back with all speed to the cave, shouted up the joyful news, and called for buckets and billies to bale with.  The King was now allowed to descend, but not unguarded, as we must first ascertain the value of our supply.  We could understand now why he had insisted on carrying with him from our last camp a burning branch (a “fire-stick");