Being soon to leave this little civilized world for a campaign in the Indian country, I take this opportunity to bequeath a few words before the moment of departure. Having sometime since obtained permission from the Secretary of War to accompany the regiment of the United States dragoons in their summer campaign, I _reported_ myself at this place two months ago, where I have been waiting ever since for their organization.—After the many difficulties which they have had to encounter, they have at length all assembled—the grassy plains are resounding with the trampling hoofs of the prancing war-horse—and already the hills are echoing back the notes of the spirit-stirring trumpets, which are sounding for the onset. The _natives_ are again “to be astonished,” and I shall probably again be a witness to the scene. But whether the approach of eight hundred mounted dragoons amongst the Camanchees and Pawnees, will afford me a better subject for a picture of a _gaping_ and _astounded multitude_, than did the first approach of our steam-boat amongst the Mandans, &c., is a question yet to be solved. I am strongly inclined to think that the scene will not be less wild and spirited, and I ardently wish it; for I have become so much Indian of late, that my pencil has lost all appetite for subjects that savour of tameness. I should delight in seeing these red knights of the lance astonished, for it is then that they shew their brightest hues—and I care not how badly we frighten them, provided we hurt them not, nor frighten them out of _sketching distance_. You will agree with me, that I am going farther to get _sitters_, than any of my fellow-artists ever did; but I take an indescribable pleasure in roaming through Nature’s trackless wilds, and selecting my models, where I am free and unshackled by the killing restraints of society; where a painter must modestly sit and breathe away in agony the edge and soul of his inspiration, waiting for the sluggish _calls_ of the civil. Though the toil, the privations, and expense of travelling to these remote parts of the world to get subjects for my pencil, place almost insurmountable, and sometimes _painful_ obstacles before me, yet I am encouraged by the continual conviction that I am practising in the _true School of the Arts_; and that, though I should get as poor as Lazarus, I should deem myself rich in models and studies for the future occupation of my life. Of this much I am certain—that amongst these sons of the forest, where are continually repeated the feats and gambols equal to the Grecian Games, I have learned more of the essential parts of my art in the three last years, than I could have learned in New York in a life-time.