But whether they were to have any more travelling or not was becoming more and more a matter of bare probability. The herbage of the valley had become reduced to mere dust, and the water had diminished so ominously as to make it apparent that, unless rain fell within a month, the party would certainly find their graves in the Rocky Glen, as one of them had already done. But the future had better things in store, and did not longer withhold them. In one of those sudden changes so characteristic of the Australian climate the sky assumed its curtain of clouds and burst in a storm of rain, which deluged the valley. The roar of the rushing water, Sturt avers, was the sweetest music that ever fell upon his ear. That welcome thunderstorm was the key which opened the door of the prison and gave liberty to the captives.
This happy release was followed by a period of successful travelling—not, indeed, void of difficulty, but yet without much of stirring incident. Another <lep6t was formed, which is well known under the name of the Park. Having enjoyed a short breathing time here, the expedition again proceeded eastward, and touched on the northern extremity of Lake Torrens. A survey of this part having been made, in accordance with special instructions, they returned to the Park Depôt, which was reached just twelve months after Sturt had left Adelaide. As time was thus rapidly passing away, he now resolved to put forth all his strength in a bold effort to reach the summit of his ambition and place his foot on the
