of January, 1845, he found the
Mackenzie River, and thence crossed on to and named the Isaacs, a
tributary of the Fitzroy coming from the north. This river they followed
up till they crossed the watershed on to the head waters of the Suttor
River. They followed this stream down until it brought them to the
Burdekin, Leichhardt's most important discovery.

Up the valley of this river they travelled, until they reached the head,
where, at the Valley of Lagoons, they crossed the watershed on to the
waters of the Gulf of Carpentaria. Here, for some unknown reason,
Leichhardt went far too much to the north, which necessitated a long
detour around the south-eastern corner of the Gulf. It was while they
were retracing a southern course along the eastern shore of the Gulf that
the naturalist Gilbert met his fate. Up to this time they had been so
little troubled with the natives that they had ceased almost to think of
a possible hostile encounter with them. This fancied immunity was broken
in a most tragic manner on the night of the 28th of June, 1845. It was a
calm, quiet evening, and the party were peacefully encamped beside a
chain of shallow lagoons. The doctor was thinking out his plans for the
next few days, Gilbert was planting a few lilies he had gathered, as was
his nightly habit when any flowers were available. Roper and the others
were grouped around the fire warding off the attacks of the mosquitoes.
Suddenly about seven o'clock a shower of spears was thrown among the
unarmed men, and Gilbert was almost instantly killed, Roper and Calvert
being seriously wounded. The whites rushed for their guns, but
unfortunately not one weapon was ready capped, and it was some time
before any of them could be discharged, when a volley caused the blacks
to scamper off. It is most astonishing that the whole of the members of
the party were not cut down in one dreadful massacre.

The body of the murdered naturalist was buried at the fatal camp, but the
grave was left unmarked, and a large fire built and consumed above it to
hide all traces of it from the natives. The river where this sad mishap
occurred now bears the name of Gilbert.

From the scene of this tragedy, which ordinary precautions would have
avoided, the party proceeded around the southern shore of the Gulf,
keeping a short distance above tidal waters; but their progress was slow
and painful on account of the two wounded men. Most of Leichhardt's names
are still retained