FRANKLIN COUNTY. 609 



First comes an eleven-inch course, some portions of which are blue in 

 color, though the prevailing color is drab. It is raised in larger blocks 

 than any other course in the quarry. Two hundred square feet are easily 

 obtained in a single, block. It is known in the quarry, on this account, 

 as the "big stone." For platforms and other like uses, it is especially val- 

 uable. 



The " big stone" is followed by a seven-inch course, which sometimes 

 yields cutting stone, but not regularly. This is followed by an eight-inch 

 course, quite blue in color, that is, on the whole, durability, size, color, 

 freedom from flint being considered, the most valuable course of the 

 quarry. It is covered by a six-inch course that serves a good purpose as 

 a curb-stone. This is followed in turn by the lower and upper " hackle- 

 tooth''' courses, the former a six-inch course, and the latter an eight-inch 

 course. These beds get their name from a sort of suture-like interlocking 

 of their apposed faces. They are quite persistent throughout the district 

 in which quarries are wrought, and serve as guides to the identification 

 ot' the several sections. The lower course is most valued for cutting, 

 chiefly because of the absence of flint from its substance. 



Next in order comes a nineteen-inch course that cannot be raised in 

 blocks large enough to make it a cutting stone. It goes in with the sec- 

 tion that lies above it, for all heavy work for which the quarries have to 

 provide. The section which we have now reached is called the " rough 

 rock." It is put down in the scale as eight feet in thickness, but it is 

 oftener four and one-half feet than eight feet. The rough rock is covered 

 by one of the most persistent layers of the quarries. It is called by the 

 quarrymen the " sheep-skin" course. It is four to eight inches in thick- 

 ness ; is raised in good sized blocks, and is largely wrought as a cutting 

 stone. The steps of the State House are, to a large extent, derived from 

 this layer. It is crowded with fossils, and these are brought out very 

 distinctly by the wear of the stone. A well-known univalve shell, the 

 Euomphalus De Oewi, Billings, belongs in this horizon, and is very often seen 

 on the slabs that belong to this course. Cyathophylloid corals also crowd 

 the surface frequently. 



Another series of building stones — in courses eight inches thick or 

 less, making an aggregate of two and one-half feet — overlies the sheep- 

 SKin course, and this in turn covered by what is called the "smooth rock," 

 which includes about four feet in thickness. There are two flint courses 

 in this interval that can be followed through the wljole belt of quarries. 

 They are easily separated from the rock in which they are bedded. The 

 latter breaks very easily, and yields the best lime of the formation. It 

 averages over ninety per cent, of carbonate of lime, and frequently rises 

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