61 



the depth of three or four feet^ is found a 

 white testaceous marble, somewhat granulated. 

 It is filled with shells of the snail kind, more or 

 less entire, which give it the appearance of shell 

 work. The quarry is several miles in extent, 

 and generally about two feet in thickness, but 

 varying according to the number of strata, which 

 are from five to eight, frequently interrupted by 

 very thin layers of sand. These strata increase 

 in hardness in proportion to their depth ; the 

 upper consists wholly of a coarse brittle stone, 

 which is only proper for lime; but the marble 

 of the others is very compact^, requires but little 

 labour to dig, and after a short exposure to the 

 air, obtains a degree of solidity and firmness 

 sufficient to resist the injuries of the weather. 



Spar, a substance common to all metallic 

 mines, and which often serves as a guide to the 

 miners to determine the character of the ore, 

 abounds in Chili, where all the known species have 

 been discovered, excepting the crystal of Iceland. 

 Of these species the varieties arc infiiiite, and 

 many of them, if examined attentively, miht 

 be found to be real and distinct species. Co- 

 loured spar, known by the nanics of false ems- 

 raid, topaz, and sapphire, is one of the speci"? 

 most frequently met with. But tb.e mf^st cu- 

 rious of all the Chilian spars is one of an hex- 

 ai>;o.!al forr.!, and perfectly tianspircnt; it is 

 found in the gold mine of Quiilata, and is 



