ALTITUDES. 



257 



the several county maps. Exceptions to this rule may occur. Our inten- 

 tion is to have the names conform to those adopted upon our geological 

 map. The most important deviations from the usage of the county 

 maps have been explained in Chapter IX. 



The results of the numerous railroad and special surveys here ex- 

 hibited, together make up a complete network of interlocking series of 

 accurately determined altitudes throughout the entire state. With this 

 as a basis of reference, it is believed that the barometrical measurements 

 of the altitudes of villages and of general sections will be found of the 

 highest value, in an inquiry into the geology, climate, and physical char- 

 acter of New Hampshire. 



TABLES OF ALTITUDES. 



I. Portsmouth to White River Junction. 



Heights along the Concord & Portsmouth Railroad. Levelled by 

 Frank and H. D. Woodbridge, in 1870, for the geological survey. Alti- 

 tudes are given above mean tide in Great bay ; distances are given from 

 Portsmouth. 



Newmarket Junction, 



Littlefield's Crossing 



Epping, 



Raymond 



Candia 



Manchester, centre of depot, 



Top of dam at Manchester, 



Amoskeag base line 



Surveys used in the Construction of the Road. From 



Piscasset river (water level) , S. Newmarket, 72 ; track. 

 Lamprey river (water level) , . 

 Same at Raymond, .... 

 Outlet of Jones pond (water level) , 

 Road at Patten's shingle mill, Candia, 

 Level of ground " " " 



Brook east of Candia depot (water level) 

 Cass's Crossing, Candia, 



Summit at Kinnecum's swamp, abandoned route. 

 Turnpike at Rowe's Corner, " " 



VOL. L 35 



