80 Exptditwn to the 



single rock or tree, large enough to be seen at the distance 

 of a mile. 



At noon, we halted near the base of a hill of this descrip- 

 tion. It is of greenstone, and the sand-rock on which it rests 

 is disclosed at the bottom of a ravine, which commences 

 near the foot of the hill. This latter rock is of a slaty struc- 

 ture, and embraces narrow beds of bituminous clay slate, 

 which contains pieces of charcoal or the carbonized remains 

 of vegetables, in every possible respect resembling the char- 

 coal produced by the process of combustion in the open air. 

 In the ravines, and over the surface of the soil, we observed 

 masses of a light, porous, reddish-brown substance, greatly 

 resembling that so often seen floating down the Missouri, by 

 some considered a product of pseudo-volcanic fires, said to 

 exist on the upper branches of that river.* We also saw 

 some porphyritic masses with a basis of greenstone, contain- 

 ing crystals of feldspar. 



In the afternoon, several magpies, shore-larks, and cow- 

 buntings were seen. One of the cow-buntings followed us 

 five or six miles, alighting on the ground near the foremost 

 of our line, and within a few paces of the horses' feet, where 

 he stood gazing at the horses until all had passed him, when 

 he again flew forward to the front, repeating the same move- 

 ments many times in succession. 



We had now arrived near that part of the country where, 

 according to the information of the Kaskaia, we expected to 

 find the remarkable saline spring, from which, we were told, 

 the Indians often procured large masses of salt. The Kas- 

 kaia had, by the aid of a map traced in the sand, given us a 

 minute account of the situation of the spring, and of the sur- 

 rounding country, stating that the salt existed in masses at the 

 bottom of a basin-like cavity, which contained about four 

 and a half feet of reddish water. Thus far we had not found 

 a single feature of the country to correspond, in the slightest 



* See Bradburj's travels, p. 161. second edition. 



