40 J. D. Dana— Geology of Vermont and Berkshire. 
portion of the Holian limestone is generally very fine in grain 
even where of the purest white color. In Pittsford and Bran- 
don are found the best of statuary marbles, looking like the 
finest loaf-sugar in texture. South of Pittsford, in Rutland, 
the marble is a little less fine in its grain than it is farther 
north ; in Berkshire, it is mostly much coarser, none answerin 
to statuary marble existing anywhere; and in southern Berk- 
shire and Canaan, Ct., it is still coarser in crystallization, and 
abounds also in many places in tremolite, white pyroxene, an 
mica. Thus the fact of intenser metamorphism to the south- 
ward is as plainly apparent in the limestones as in the schists. 
After this survey of the facts we have to admit that the differ- 
ences are so distributed shee ie tle as to prove unity of 
area and rocks, rather than diversi 
eiss ; and then coarser and harder ener of the latter 
rocks ; "and the crystalline limestone, which is almost free from 
foreign erystallizations in Stockbridge and West Stockbridge, 
contains large crystallizations of white pyroxene or tremolite 
in some places in Lee, Monterey and Tyringham. 
2. Tue STRATIGRAPHICAL RELATIONS. 
In Vermont we have found the following cases of conform 
le su; tion or interstratification, as described in the ens 
of Mr. Wing’s researches, and illustrated in the figures of sec- 
tions accom ng. 
(1.) Th fe ee and schists conformable. 
ies quartzyte and schists conformable. 
The quartzyte and limestone, and also the quartzyte, 
achnte and limestone, conformable. 
The first of these Vermont cases of conformability is illus- 
trated in the sections on pages 338, 340, 344, 346, 347 of the 
last volume of — Journal ; pest soon in the suai a 
the quartzyte ormation, as explained on e411; the thi 
in the sections presented on pages 340 and 412, 
The following facts show that hte Ey similar cases of con- 
formable superposition exist in Berks 
