the Lead Mines of Missouri, ^-c. 65 



only granite between the Alleghanies and the Rocky moun- 

 tains, we are lead to ask — is it a portion of the nucleus of 

 our globe, covered on every side, for many hundred miles, 

 with secondary rocks, and here heaving its head through the 

 superincumbent strata, and standing alone ? 



But, what are we to conclude of the lime stone ? Al- 

 though Mr. Schoolcraft states that the granite is every 

 where surrounded by secondary hme stone, he remarks in 

 several places that the country is based on primitive lime 

 stone : as at page 92, " the whole mineral country is bot- 

 tomed on primitive lime stone"— at the sam-e time he 

 adds, that " secondary hme stone is met with, but that it is 

 far less common than in Ohio, Indiana," h.c. At page 108, 

 speaking of the hme stone, which, he says, is the rock inva- 

 riably met with in digging, and generally at the depth of 

 fifteen or twenty feet, he remarks, that there are many va- 

 rieties of it, the texture varying from very hard and com- 

 pact, to soft and friable — the latter crumbling between the 

 lingers, and being called rotten lime stone : lime stone, he 

 says, is invariably the basis on which the mineral soil at 

 Mine a Burton, and the numerous mines in its vicinity re- 

 poses. He speaks of it as " passing into transition and sec- 

 ondary lime stone, in various places on the banks of the 

 Mississippi, between Cape Girardeau and St. Louis, and as 

 becoming a variety of marble near Herculaneum." He does 

 not inform us whether this primitive lime stone is crystal- 

 line in its structure, or translucent, if not crystalline. He 

 generally speaks of it as compact, and if he uses the word 

 compact, in the sense to which Mr. Werner's descriptive 

 language limits it, we must remark that compact lime stone 

 is rarely if ever primitive — the structure of this latter being 

 almost always crystalline, and if ever compact it will gene- 

 rally be translucent also, at least on the edges, but if com- 

 pact and a secondary lime stone, it will in most instances be 

 perfectly opake. The compact translucent lime stone is gen- 

 erally of the transition, and not of the primitive class. 



The term marhle, sometimes introduced by Mr. School- 

 craft, is not distinctive — perhaps it was not intended to be 

 so ; for the marbles, it is well known, are derived from all 

 the divisions of . lime stone, primitive, transition and secon- 

 dary. Nor is the absence of " shells, (p. 108) animalcula, 

 or other traces of animal life" conclusive ; their presence 

 Vol. m No. 1. 9 



