328 



STRATIGRAPHICAL GEOLOGY. 



schists, including calcareous limestone, a drusy rock, and diabase, dip 



85° N. 80° W. At A. P. Hubbard's, exactly upon the section line, the 



i dip is 85° S. 30° E. The soft clay slate is thin-bedded, 



tc jointed but not contorted. The same position continues 



I two thirds of the way to the house of J. Shute. The 



J, last third of the way the slate resumes the dip of N. 30° 



^" W., and disturbances are common. The cleavage planes 



§ can also be distinguished from the strata in a few ledges. 



-^ The quartzite is a rough-looking rock, somewhat like 



^ buhrstone, dipping even as low as 35° N. 30° W. The 



i; i band of chlorite schist dips 75°-8o° N. W., and corre- 



1^^^ spends to a similar rock in the next section holding the 



^. c same position. Last of all is the gneiss, dipping at a 



^: s moderate angle in the same direction, and probably un- 



I 5 derlying unconformably the whole series described. This 



^ I section is four hundred and twenty rods long. The slate 



a,' -^ 



.-< I is estimated to be 1490 feet in thickness. 



'? The slate is continuous from Fig. 37 to Fig. 38, grad- 



I ually narrowing, and disappearing before reaching the 



I section in Fig. 39. That which appears on the latter oc- 



^~ cupies a slightly different line. Fig. 



'i 38 crosses the best locality of buhr- 



;! stone, from E. P. Miner's, on a tribu- 



i tary of Parker brook, and an eighth 



"^- of a mile north of the Littleton cem- 

 etery. It is one hundred and sixty rods long. The 

 western edge of the gneiss appears at Miner's. The 

 chloritic layer is mostly concealed by drift. The buhr- 

 stone crops out on the hillside: it is quartz, massive 

 and brecciated, sometimes jaspery and opaline, with a multitude of seams 

 covered by quartz crystals. About forty feet in thickness of it are ex- 

 posed. Following up the hill, we find next the slates, the limestone 

 being concealed by drift. It appears in a place only a few rods to the 

 south of the section. The slate is bent everywhere, and shows a ten- 

 dency to contain drusy quartz. Two measured dips are 70° N. 70° W., 

 and 85° N. 80*^ W, Other strikes are more easterly. The section, if 



