From this it will be seen, that to the mineralogist, few objects of interest are found. The masses of pumice, and the burnt bluffs in the country of the Poncas, are to be attributed most probably to the burning of coal banks; for it is a well known fact, that such have been known to burn for several years without being extinguished; and why may not the same thing have occurred here. In one place above the Poncas village, the river is bounded on both sides by hills of no great elevation, bare of vegetation, and the earth from the effects of burning, in nearly the whole of this distance, of a dark color, quite hard and heavy, as if containing a portion of iron. Emetites are observed in considerable quantities, from which it is probable that iron ore exists.
Mr. Bradbury has met with but little on the subject of mineralogy; but has been very successful in his botanical researches. He has encountered nearly an hundred undescribed plants, many very beautiful and curious. Within a few days he finds a great number which he calls Mexican. We have now in fact reached that inclined plain over which the rivers of the Provincias Internas, run into the {119} Gulf of Mexico. There are also many alpine plants, by which he conjectures, that we have already attained a much greater height, than any part, of the Eastern section of the valley of the Mississippi. Mr. Bradbury, in company with some Indians and hunters has made an excursion from the river Platte, to the Otto villages on that river, to the mouth of Elkhorn, which he describes as a deep navigable stream, containing nearly as much water as the Thames at London bridge, but this water is swallowed up in the shoals and quicksands of the river, into which it is discharged. He passed for one hundred and fifty miles, through a delightful champaign country, of rich, open, smooth meadows, the borders of the streams fringed with wood: within eight or
