Another result was the establishing a line of telegraph from Adelaide to Port Darwin.

This might therefore be considered the eastern boundary of the unknown districts, and moreover was the point of departure for the South Australian expeditions in a westerly direction.

It was also the limit I desired to reach, and, reaching it, I should achieve the object I had so much at heart.

Of the South Australian expeditions, only one was successful in getting to the western colony, and that one, led by Colonel Warburton, involved much suffering and was comparatively barren of practical results.

Besides, as we afterwards knew, the route selected by him was so far to the north as not to interfere with my project.
The following letter to me expresses the official estimate of the result of Colonel Warburton's expedition:-- Surveyor-General's Office, Perth, March 27th, 1874.
The gist of the information I have from Colonel Warburton may be summed up in a few words.