GEOLOGY OF THE MERRIMACK DISTRICT. 543 



New Boston and Lyndeborough on the Hooksett range, in the absence 

 of continuity in the rock, and its recurrence five miles distant on a differ- 

 ent line of exposure. It appears next on the south side of the Souhegan 

 river in Milford, back of the school-house situated upon a triangular 

 area produced by the intersection of roads. The course from the last 

 locality of the quartz vein in Amherst to this new exposure is S. 65° W. 

 The quartz dips 75° N. 70° W. It is more gray than usual, almost 

 passing into gneiss, and very abundantly traversed by reticulating veins 

 of milky-white quartz. It occupies a hill, and may be followed as a ridge 

 for about two miles. At B. Gray's, just within the town of Wilton, the 

 quartz dips 80° N. Tj° W. Other exposures occur in the south-east 

 corner of Wilton. The last ledge of this range that has been found is 

 situated near I. A. Brown's, in the north-east corner of Mason, with the 

 strike N. 15° E., and dip N. 75° W. The country along the proper 

 place for the continuation of the quartz, and all the adjacent towns, have 

 been carefully explored in search of further exposures; but, like the other 

 range, this seems to come to an abrupt termination, and the proper 

 explanation of its behavior remains to be satisfactorily set forth. It 

 may be stated, however, that two parallel ranges of similar quartz occur 

 in Royalston, Mass., the northern about two miles south of a Baptist 

 church, and the southern close by the village of Pine Dale. One of 

 them comes within the limits of our general map, where it is designated. 

 It is twenty-one miles from the last exposure in Temple, and the direc- 

 tion is S. 62° W., almost in the proper place for the extension of the 

 Hooksett range. Both older and newer formations intervene, and I am 

 disposed to think the Royalston ranges belong to another fold, and con- 

 sequently a parallel line of exposure, 



A few words about the relations of these ranges to each other. At 

 their beginning in Hooksett they are four and one tenth miles apart. 

 They gradually diverge till we reach the breaks in New Boston and 

 Amherst, where they are seven and a half miles apart, directly op- 

 posite each other, the extreme ends being eight and two tenths miles 

 distant. The next appearances in Lyndeborough and Wilton are four 

 and three tenths miles apart, and their south-western termini in Temple 

 and Mason are seven and two tenths miles apart. At Royalston the 

 exposures are four and a half miles distant from each other. Before 



