The horses were constantly bogged in the deep mud, and losing condition rapidly. John McKinlay eventually decided that he must kill all of them and use their hides to construct a punt to sail downstream to meet up with the Government Schooner Beatrice. The Beatrice had been assigned to carry supplies for the expedition to the mouth of the Liverpool River further to the east, supplies which McKinlay would never receive as he came nowhere near the mouth of that river, but was on the East Alligator River under the cliffs of Arnhem Land. Using saplings for the framework and the green hides of the horses and the canvas of one of the tents, the expedition embarked on the river, to sail down the East Alligator River and eventually around the coast to Escape Cliffs.

John McKinlay had been commissioned in 1866 by the South Australian government to explore the Northern Territory and in particular to look for a site for the main settlement which at that time was at Escape Cliffs in Adam Bay and was unsuitable for long term occupation. He left Escape Cliffs in January 1866, not fully realising the impact the arrival of the wet season would have on the country. He was equipped with 45 horses, a number of sheep for meat on the hoof and with 14 men including Francis Thring from John McDouall Stuart's expedition of 1862 and Robert Edmunds as surveyor. The country was already flooded and the country along the course of the Adelaide River and east of it was a wilderness of morass and tortuous hills. The horses were dying, worn out by the conditions and the mud from which they were continually being wrenched. Edmunds and McKinlay were also constantly in disagreement.