422 Expedition to the 



we are by no means anxious to maintain the position we have 

 assumed. Our examinations have been limited, and we shall 

 rejoice in any opportunity we may have for correcting our 

 errors, and enlarging our acquaintance with this interesting 

 range of country. 



We subjoin from Mr. Jessup's report some account of a 

 few of the most interesting minerals hitherto observed in 

 connexion with the rocks of this district.* 



* Fluate of Lime. — This mineral occurs ia great abundaoce, seventeen 

 miles south of Shawaneetown, Illinois, on Peter's creek, and proceeding 

 about thirteen miles ia a southwest direction, it again appears on and near 

 the surface of th^ ground, at the three forks of the Grand Pierre creek; 

 maintaining the same course, it breaks out in several places for near twen- 

 ty miles. This beautiful and useful species of lime, occurs at Peter's creek 

 almost invariably in a crystallized form; the crystals are universally cubes: 

 at the three forks of the Grand Pierre creek, it occurs in masses of se- 

 veral feet in diameter. Both the crystallized and massive varieties, possess 

 almost all the shades of color that have been observed in the European spe- 

 cimens; VIZ. green, violet, blue, red, yellow, white, black, and rose color- 

 ed. — This mineral varies in transparency, some specimens being perfect- 

 ly limpid, others opaque. Some of the violet, and rose coloured specimens 

 when recently fractured or pulverized, yield a strong bituminous odor, 

 this character (which has never been observed heretofore, as belonging 

 to this species of mineral) is perceptible only in the crystallized speci- 

 mens. 



The vein of fluate of lime is apparently very extensive; very few mi- 

 nerals have been found associated with it, at the above localities. I saw at 

 Peter's creek a few specimens of laminated calcareous spar, and a few of 

 sulphuret of lead. Excavations have been made by several gentlemen 

 who reside in that vicinity, for lead, but no veins or beds of this ore have 

 been found. From examination of the situation of those specimens which 

 I found, and the general appearance of the vein of fluor spar, I do not 

 think that there is a sufficiency of lead ore, to reimburse the expenses 

 that would be necessarily incurred in mining. The accompanying rocks 

 of the vein of spar, are compact limestone, sandstone, and oolite. 



Concreted Carbonate of Lime. Variety Oolite. — This occurs on Peter's 

 creek, seventeen miles south of Shawaneetown is associated with com- 

 pact limestone, and sandstone in the gangue of the fluate of lime. It is 

 composed of globular masses, about the size of English mustard seed, 

 which are united by a calcareous cement; the nuclei of the globules are 

 detached leaving a small cavity in the centre of each; its colour is yellow- 

 ish white; fracture dull. 



Sulphuretted Hydrogen Gas. — This gas is very abundant in the water 

 of many of the springs and wells in Missouri territory. Its origin is proba- 

 bly owing to the decomposition of sulphuret of iron. Six miles west of 

 St. Louis, is a large spring of water, stro*ngly impregnated with this gas; 

 its odor is perceptible to tlie distance of four or five hundred yards from 

 the spring. It is reported that the water has proved beneficial io cases of 

 cutaneous disorders and rheumatic complaints. 



Red Oxide of Iron. — This occurs (though not very abundant,) in the 

 hills near Isle a Loutre, on the Missouri river. Its texture is compact, 



