84 ECONOMIC GEOLOGY. 



thickness. Massive garnet and crystals of hornblende occur in connec- 

 tion with the enclosing beds. Dr. Jackson describes a mixture of lime- 

 stone and granular quartz on the same farm 120 feet in thickness. Anal- 

 ysis shows it to be quartz mixed with silicate and carbonate of lime. It 

 consists of silica, 80.40; lime, 14.72; magnesia, 1.12; oxide of iron, 0.88; 

 carbonic acid, 2.88=: 100. It was recommended for the manufacture of 

 glass. On Holt's hill is a bed of limestone one foot thick, in company 

 with iron pyrites. The limestone crops out conspicuously in East Lyme 

 where the road branches to Dorchester and Canaan. The region of these 

 limestone beds in Orford and Lyme is now very sparsely inhabited, inso- 

 much that the road at the west base of Smart mountain is almost impass- 

 able. 



Littleton. Lime has been burnt in the Helderberg limestones of Lit- 

 tleton in at least two places. One is about three miles to the north of 

 the village on Burnham's hill. Two extensive openings occur here, show- 

 ing a breadth of stone from 10 to 60 feet thick. The other locality is on 

 Parker brook, about a mile west from the depot. Both these kilns were 

 in action some thirty years since, and produced an excellent quality of 

 lime. It was brown after burning, but slacked white. The amount of the 

 stone is abundant, as has been mentioned in the discussion of the Hel- 

 derberg formation. The stone near Parker river is unusually white. 

 Another mass of stone, seemingly 40 feet wide and of better quality than 

 the last, occurs on Fitch hill, a mile south-west from the brook locality. 

 This rock forms a knob in a pasture beyond the best fossil outcrop. Still 

 another opening occurs back of J. K. Corey's house, in the south part of 

 the town, near the Ammonoosuc river. By examining the geological 

 map, one will see that the Helderberg group extends southerly upon 

 both flanks of Blueberry hill; and good outcrops of limestone may be 

 looked for in almost any part of the blue-colored areas. That for a mile 

 along the river in North Lisbon is largely composed of a white lime- 

 stone, but it is not free from silica and rock, and would not answer so 

 well for the manufacture of quicklime. 



It is our belief that nearly all the beds mentioned are capable of 

 furnishing a good quality of lime. It is equally strong with that fur- 

 nished from Maine, but usually makes a brown mortar like that from 

 Weathcrsficld, Vt., which, by the way, is exactly the same material as 



