STEATITE. 



537 



Fio. 282. 





Section in Qoodrich's Quarry. 



situated in Grafton. The latter is northeast (N. 50 E.) from the former. Very much might be said 

 respecting the position of the different kinds of rock in these quarries, but we must limit ourselves to the 

 description of a small portion of them in detail. At the east end of G-oodrich's quarry we find the following 

 layers exposed to view in the excavation : On top is gneiss dipping 26 northerly, thickness not given. 

 Next is a bed of disintegrated talcose schist, one and a half feet thick. Next is a bed of very much con- 

 torted talcose masses, four feet thick. Next is a bed of steatite, three feet thick, followed by four feet 

 thickness of a very tough hornblende rock, ringing like iron when struck with a hammer. Below this is a 



bed of steatite, four feet thick. At this point 

 the bottom of the quarry is reached. Adjoining 

 this vertical section, upon the east wall of the 

 quarry, the position of the different rocks is given 

 in Fig. 282. The steatite occurs in lenticular 

 masses, as A, A, A, and C. B represents horn- 

 blende rock and talcose aggregates, which occupy 

 the greater part of the section. D represents 

 gneiss overlying the magnesian rocks. At the 

 right hand of the figure a large amount of debris is represented. Thus the steatite and associated rocks at 

 this quarry are seen to be interstratified with one another, and forming irregular beds, the persistence of 

 which cannot be depended upon. Generally in other localities the steatite or the hornblendic rock occur 

 in one or more large beds by themselves. The steatite is all of excellent quality, and is highly prized by 

 workers in soapstone. Upon an old opening, some twelve rods distant from Goodrich's quarry, to the south- 

 west, we saw a good illustration of the manner in which a bed of steatite or associ- 

 ated rock may thin out, giving place to some other rock. It is represented in Fig. 

 283. A is a bed of steatite, ten feet wide, inclosed in gneiss, C, 0. Associated 

 with the steatite is a narrow bed of hornblende rock, B, not more than a foot wide 

 at the surface. As the bed is quarried, the bed B rapidly increases in size, and at a 

 depth of fifteen feet has occupied most of the space at first monopolized by the stea- 

 tite. If the examination could be carried deeper into the earth, the steatite might 

 be replaced entirely by the hornblende rock, or the steatite may expand again at the 

 expense of the hornblende rock. We present this case as nothing peculiar to Good- 

 rich's quarry, but as a sample of what may occur in every bed of steatite or serpen- 

 tine. What we have called hornblende rock here is really a homogeneous compound intermediate between 

 serpentine and hornblende rock. As the lenticular masses of steatite and serpentine are so common, it is 

 no wonder that it is a question with many how these beds were originally derived : whether from aqueous 

 or igneous, or aqueo-igneous forces, or could they have been pockets in the rock which were filled up by 

 chemical deposition ? 



Smith's quarry is in general similar to Goodrich's ; but the steatite is more uniformly in one mass. Fig. 



284 represents a section at the north side of 

 Smith's quarry. A, is steatite fifteen feet thick ; 

 B, represents masses of hornblende and talc ten 

 feet thick ; and C represents the overlying gneiss* 

 This quarry will be exhausted sooner than the 

 other. Owing to the peculiar nature of these 



Fio. 283. 



Steatite in Athens. 



Fio. 284. 



Section at Smith's qnany. 



masses of steatite we have found it impossible to sketch these beds of steatite in outline, like those in Marl- 

 boro. There is a curious tendency, in these as in other beds, of the strata to increase their inclination 

 beneath the surface. For example, in Smith's quarry we noticed strata, at the surface dipping twenty 

 degrees, but presently standing at an angle of eighty-five degrees. 

 35 



