The plot of Rose to rob and abandon his countrymen when in the heart of the wilderness, and to throw himself into the hands of savages, may appear strange and improbable to those unacquainted with the singular and anomalous characters that are to be found about the borders.  This fellow, it appears, was one of those desperadoes of the frontiers, outlawed by their crimes, who combine the vices of civilized and savage life, and are ten times more barbarous than the Indians with whom they consort.  Rose had formerly belonged to one of the gangs of pirates who infested the islands of the Mississippi, plundering boats as they went up and down the river, and who sometimes shifted the scene of their robberies to the shore, waylaying travellers as they returned by land from New Orleans with the proceeds of their downward voyage, plundering them of their money and effects, and often perpetrating the most atrocious murders.

These hordes of villains being broken up and dispersed, Rose had betaken himself to the wilderness, and associated himself with the Crows, whose predatory habits were congenial with his own, had married a woman of the tribe, and, in short, had identified himself with those vagrant savages.

Such was the worthy guide and interpreter, Edward Rose.  We give his story, however, not as it was known to Mr. Hunt and his companions at the time, but as it has been subsequently ascertained.  Enough was known of the fellow and his dark and perfidious character to put Mr. Hunt upon his guard:  still, as there was no knowing how far his plans might have succeeded, and as any rash act might blow the mere smouldering sparks of treason into a sudden blaze, it was thought advisable by those with whom Mr. Hunt consulted, to conceal all knowledge or suspicion of the meditated treachery, but to keep up a vigilant watch upon the movements of Rose, and a strict guard upon the horses at night.

CHAPTER XXV.

Substitute for Fuel on the Prairies.—­Fossil Trees.—­ Fierceness of the Buffaloes When in Heat.—­Three Hunters Missing.—­Signal Fires and Smokes.—­Uneasiness Concerning the Lost Men.—­A Plan to Forestall a Rogue.—­New Arrangement With Rose.—­Return of the Wanderers.

The plains over which the travellers were journeying continued to be destitute of trees or even shrubs; insomuch that they had to use the dung of the buffalo for fuel, as the Arabs of the desert use that of the camel.  This substitute for fuel is universal among the Indians of these upper prairies, and is said to make a fire equal to that of turf.  If a few chips are added, it throws out a cheerful and kindly blaze.

These plains, however, had not always been equally destitute of wood, as was evident from the trunks of the trees which the travellers repeatedly met with, some still standing, others lying about in broken fragments, but all in a fossil state, having flourished in times long past.  In these singular remains, the original grain of the wood was still so distinct that they could be ascertained to be the ruins of oak trees.  Several pieces of the fossil wood were selected by the men to serve as whetstones.