PHYSICAL HISTORY OF NEW HAMPSHIRE. 513 



of the finest exposures of it lies in the towns of New Hampton and 

 Meredith. At Lake Village it is the most common stone used for under- 

 pinning. Along the Boston, Concord & Montreal Railroad, from Ashland 

 to Lake Village, ledges of it are frequent ; also, along the Northern Rail- 

 road, between West Andover and East Canaan. The rock is grayish, 

 rarely dark brown, with rectangular spots thickly scattered over it vary- 

 ing in size from one fourth of one to two or three inches long, and a 

 fourth part as wide. These crystals of feldspar are sometimes arranged 

 in lines, their longer axes being parallel one to another, or they may be 

 thrown together indiscriminately. This difference in arrangement indi- 

 cates, perhaps, the degree of intensity with which heat has acted upon 

 the rock. The first are akin to strata of gneiss ; the second is a granite, 

 resulting from the aqueo-igneous fusion of the first. The fusion must 

 have been protracted and the material very plastic, in order to permit 

 the development of such large and abundant crystals. 



It is probable that some of these islands were united at this first time 

 of elevation, though they are now separated by other material of later 

 origin, formed partly from the degradation of the former, and deposited 

 upon it. There has been much crowding of the older rocks in subsequent 

 periods, so as to compress what may have been a large island at first into 

 an insignificant patch. It would not be surprising if this archipelago 

 originally covered as much area as the two states of New Hampshire 

 and Vermont combined. Our representation must therefore fall some- 

 what below actual truth. The widest stretch of the imagination can 

 mark out a possible arrangement of these primeval areas, but it would 

 not satisfy the mind so well as the delineation of their present limits. 

 With this explanation presented, the reader may conceive the separation 

 of these areas over a greater range of longitude than is permissible 

 within the present state limits. There would not be much variation in 

 the length, as the crowding in later times came from the east or west. 



This archipelago must have been considerably isolated from every 

 other existing territory in this ancient period, since we must go a long 

 way in any direction to find the same formation. It is entirely unknown 

 in Vermont, but crops out in the Adirondacks, and north of the St. Law- 

 rence, in Canada. Very little is known of the rocks in western Maine, 

 so that it cannot positively be said to be wanting there, though I have 

 VOL. i. 67 



