3GO BEDS OF OTHER ROCKS. 



figure represent the lines of cleavage, which generally coincide with the planes of sti-ati- 

 fication. The position of the layers of quart/ is indicated by the ten spaces in the figure. 

 These layers vary from one half of an inch to five inches in thickness. Were it not for 

 these layers it would be impossible to distinguish the marks of stratification from the 

 superinduced planes of cleavage. The strata makes a graceful inverted fold, dipping 39 

 east. This sketch was taken by Mr. Hager from the south end of the quarry. About 

 eighty rods north of Barrett & Barnes' quarry, there is a similar curvature of slate and 

 quartz layers ; but the layers of quartz are thinner and fewer. 



In Allen's north quarry in Fairhaven, the quartz layer is 6 feet thick. E. Hitchcock, jr. 

 says that in all the quarries of roofing slate in this vicinity, numerous beds of granular 

 and crystalline quartz, and also beds of limestone are found. 



" From Highgate Falls to West Berkshire there are successive ranges of slate inter- 

 stratified with quartz. This slate is of a light greenish hue, and appears somewhat chlo- 

 ritic." Z. Thompson. 



The beds of limestone associated with the clay slate are numerous and of varied forms. 

 The largest belt is often two miles wide, and will be described under Eolian limestone. 



Other large beds of limestone may be traced over many miles along the line of strike. 

 In the southern terrain, the limestone is generally a bluish-brown compact rock containing 

 considerable silica ; and fetid when roughly fractured. When it is completely filled with 

 white anastomosing veins of calcite or white quartz, it presents a beautiful appearance, 

 and constitutes the rock called sparry limestone. It is often the same as the sparry 

 limestone of the Taconic system, when it is quite thick. That term as used by Emmons 

 is more extensive than we use it, for he includes under it all masses of limestone 

 bounded on both sides by Taconic slate. By consulting the details of the first seven 

 general sections a large number of beds of limestone will be found noticed. 



Among the slate quarries in Rutland County the limestone occurs in numerous thin 

 beds of several inches in thickness. It has nearly the same color as the slate, and must 

 occasion some trouble to quarrymen in many localities. 



The notes of E. Hitchcock, jr., give the following section of the West Castleton Rail- 

 road and Slate Company: Upon the top of the quarry there is 



Taconic slate, 30 to 40 feet thick ; and following it are 

 ^ Sparry limestone, . 6 feet ; 



Green slate, . . .6 feet ; 

 Purple slate, . . 45 feet ; 



Green slate, . . .6 feet ; 



Total, 118 feet. 



William Hughes' quarry in Castleton, is overlaid by sparry limestone, often concretion- 

 ary, and often interstratified with a decomposing slate. 



Sometimes the beds of limestone, in the Georgia slate, are brecciated. There is one 

 of this kind in Fairhaven (No. ~, in the Cabinet); the fragments of which the breccia 

 is composed are of a blue color, somewhat resembling the common variety of Trenton 

 limestone. There are no fossils present to decide whether the fragments were derived 

 from the Trenton or Eolian limestones. 



