To him the two escaped desperadoes came with a complaint against the Yumas, but the captain was posted and he put the men in irons to be transported to California for trial.

The Yumas now established a ferry by using an old army-waggon box which they made water-tight, as the Craig Ferry had suffered the fate of its owners.

Hobbs employed the Yumas to take his party over, the horses swimming, and the arrangement seems to have worked very well.
According to Hobbs, the first steamboat came up the river while he was there, frightening the Yumas so that they ran for their lives, exclaiming the devil was coming, blowing fire and smoke out of his nose, and kicking back with his feet in the water.

It was the stern-wheel steamboat Yuma, and this is the only mention of it I can find.

It had supplies for the troops, but what became of it afterward I do not know.
This was evidently before the coming of the Uncle Sam, usually credited with being the first steamboat on the Colorado, which did not arrive till a year after the reconnaissance of the river mouth by Lieutenant Derby of the Topographical Engineers, for the War Department, seeking a route for the water transportation of supplies to Fort Yuma, now ordered to be a permanent military establishment.