450 J. D. Dana on the Quartzite, Limestone, etc., 
Art. LIV.—On the Quartzite, Iimestone and associated rocks of 
the vicinity of Great Barrington, Berkshire Co., Mass. ; by 
James D. Dana. 
(Continued from page 370.) 
3. Stratification. 
(a.) Monument Mountain, and the Housatonic Valley adjoining 
ut on the west. 
Monument Mountain has a precipice of hard quartzite on Its 
eastern front,* and a wall of the same rock along the sides 
facing southwest and west, while through the interior the rock 
is mica schist and gneiss. 
of these joints have gin a north-and-south direction 
mountain near its southwestern side. 
2 
Mount re and the Taconic range to the southwest, and, nearer 
_ beautiful valley of the Housatonic, with its lakes and villages. i ae 
+ ae ee oe a Oe ee are compass courses. The variation 
_ Barrington region is about 8}° W., which would make N. 10° E, compass cous? 
_ correspond to . 14° E. true course. 2 
