Plrsson and Washington — Geology of Red Hill, N. II . 257 



Art. XXIV". — Contributions to the Geology of New Hamp- 

 shire, No. III. On Red Hill, Moultonboro ; by L. V*. 

 Pirsson, with analyses by H. S. Washington.* 



Introduction. — This article embraces the results of a field 

 and laboratory study of the igneous rocks which compose the 

 mountain in Moultonboro, N. H. known as Red Hill. This 

 eminence is one of the most prominent objects in the lake 

 district of the state and, situated nearly on the shores of both 

 Lake Winnepesaukee and Lake Asquam, its top commands one 

 of the most beautiful panoramic views in New England. For 

 this reason and because it is easily climbed it is frequently 

 visited by tourists and the summer residents of the region. 

 The origin of its name, in spite of several ingenious theories 

 advanced by writers on the region, is involved in mystery; 

 there is nothing red about its rocks or its foliage which espec- 

 ially distinguishes it from the other mountains of the region, 

 and like many another place name it is probably due to some 

 long forgotten trivial circumstance connected with the early 

 settlement of the country. 



Both the mountain and the country surrounding it have 

 been visited several times by the writer for study and the collec- 

 tion of material. On one occasion a week was spent in this 

 work, during which it was encircled and the contact studied 

 at a number of places, its peaks and crest line visited and trav- 

 erses of the mass made in several directions. It was during 

 this visit that I was accompanied by Dr. Washington, who 

 studied the field occurrences with me. 



Historical. — The earliest mention of the geology of Red 

 Hill, which I have been able to discover, was by Prof. O. P. 

 Hubbard, f who speaks of it as a mountain consisting of red- 

 dish syenitic granite whose sides are covered with decomposed 

 fragments of the same rock. He says it is cut by two trap 

 dikes, one in width seven feet, the other twenty-five, whose 

 trend and location are somewhat vaguely given. 



Prof. C. T. Jackson;}; describes the mountain as composed of 

 a beautiful syenite whose feldspar is an ash-gray color when 

 fresh, but weathering to a reddish color. He also mentions 

 a trap dike of a porphyritic texture on the west side and 

 speaks of the well crystallized hornblende in the syenite ; says 

 that bog iron occurs on the mountain in small quantity and 



* In addition to making the analyses, Dr. Washington accompanied me 

 during the greater part of the field-work and has since placed his collected 

 material and sections at my disposal, thus conferring obligations upon me 

 which I am glad to take this opportunity of acknowledging. 



f This Journal (2), xxxiv, p. Ill, 1838. 



% Geology of New Hampshire, 1844, p. 71. 



