Rocky Mountains, 417 



Specimens of the substance called chalk by the inhabitants, 

 were collected at several places between cape Girardeau and 

 Saint Louis; also on the north side of the Missouri, on the 

 road from St. Louis to Franklin. Some of these, which were 

 brought to New York, have been examined by my brother, 

 Dr. J. James, and others, and were found to consist princi- 

 pally of alumina, none of them occasioning the slightest ef- 

 fervescence with acids. 



This substance, whatever it is to be considered, is distri- 

 buted extensively throughout the country lying around the 

 confluence of the Missouri and Mississippi. Some speci- 

 mens have been sent from Illinois to the Lyceum of Natural 

 History at Troy, where they are spoken of as a " lithogra- 

 phic carbonate of lime;" but whether any experiments have 

 been made to ascertain their real character, we have not 

 been informed. We have not, from our own observation, 

 found occasion to confirm the statement, that nodules of flint 

 are found imbedded in this substance, but we have common- 

 ly found it accompanied by the flint rock, already described, 

 which has in many respects a manifest resemblance to the 

 flints occurring in chalk formations. We have sought in 

 vain for the remains of echini and other animals, so com- 

 mon in chalk beds. 



It must remain for those who shall hereafter investigate 

 the geology of the Ozark mountains, to assign the place, and 

 more satisfactorily to ascertain the character of this peculiar 

 formation. It may possibly be found to occupy a position 

 analogous to that of the chalk formations of England and 

 France, its magnitude and extensive distribution entitle it to 

 consideration as a distinct stratum. '* 



We now return to the limited formations below the car- 

 boniferous limestones. These occur principally in the south- 

 ern section of the Ozark mountains. 



V. — Inclined Sandstone. 



This is first in order, below the coal series, but seems so 



fire with steel; the fracture is conchoidal, and the edges are translucent. 

 The veins of flint dip to the southeast. — Ihid. 



Imbedded in the chalk of Cape Girardeau, are occasionally found no- 

 dules of flint, which are enveloped by a hard crust of calcareous carbonate, 

 arranged in concentric layers. Its colour is grayish black; breaks with a 

 perfectly conchoidal fracture; is transparent on the edges, and readily 

 gives fire with the steel. 



SchoolcrafVs yiew of the Lead JUines, p. 180. 



We have yet no satisfactory information of the existence of chalk, IrB- 

 yondthe limits of Europe — Conybeare and JPhillipps, p- 67, part l. 

 VOL. II. 53 



