Page:Encyclopædia Britannica, Ninth Edition, v. 17.djvu/415

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NEW HAMPSHIRE
391

chestnut, mountain laurel or Kalmia, grape, and cran berry. A few characteristic animals of the Canadian district are the rose-breasted grosbeak, Canada jay, spruce partridge, crossbill, snowbird, caribou, and Canada lynx ; the absence of reptiles is marked. A few of the trees are spruces, balsam fir, canoe birch, and bush maples. This district, comprising the northernmost county, reaches the height of 40QO feet, or the upper limit of trees. The Hud son district is a region of dwarfed spruces extending above the Canadian upper limit to the 5000 feet line, and limited to the White Mountains. None of the larger animals which flourish about Hudson s Bay could be expected in such limited and mountainous peaks, so that the proof of the presence of this fauna is afforded by the plentiful distribu tion of the butterfly known as Brenthis montinus and the grasshopper Pezotettix glacialis. Owing to the small areas occupied by the Hudson and Labrador floras in the White Mountains, botanists have not yet succeeded in separating the plants peculiar to each. Fifty-three species are referred to them, called the sub-alpine and alpine districts, embracing such genera as Arenaria, Geum, Solidago y Potentilla, Nabalus, Cassi<ype t Rhododendron^ Salix, Saxifraga, Diapensia, Carex, Poa, &c. The Labrador fauna is specially characterized by the abundant presence above the 5000 feet line of the butterfly Oeneis semidea. The presence of these faunal islands in the midst of the Canadian district is accounted for by the greater coldness of the climate in the glacial period. The whole country was then overspread by the peculiar animals and plants of the Arctic regions. As the climate moderated these organisms migrated both northwards and upwards into the higher districts, where they found the conditions favourable to their existence. Those which ascended the mountainous regions soon became separated from their congeners by the warmer temperature of the lowlands, and are now securely imprisoned in these mountain fastnesses.

New Hampshire was originally nearly covered by a dense forest. In 1876 it was estimated that more than one-fourth of the territory was still covered by trees, not of the original growth, but occupying land that had not been cleared. The trees valued for lumber, growing naturally in the forest, are the white, red, and pitch pines, spruces, hemlock, larch, red and sugar maple, beech, birch, red and white oak, chestnut, elm, hickory, poplar, cherry, &c. The pines have been described by the early settlers as commonly exceeding the height of 200 feet. One that was cut upon the Dartmouth College grounds measured 270 feet in length.

Geology. The topography has a less intimate connexion with the geology. The rocks are nearly all crystalline, and show very few peculiarities of sculpturing except the eruptive massive granites. These are more or less conical, like volcanic accumulations of modern times. Examples may be seen in Mount Chocorua, Mount Pequawket, and Mount Moat. At the base is a coarse porphyritic gneiss, not less than 5000 feet thick. This shows itself principally along the Connecticut- Merrimack watershed south of the White Mountains. Next comes a protogene gneiss, saccharoidal and easily crumbling, having the same thickness, and developed most extensively in Cheshire county. A third gneissic group, 18,000 feet thick, was first separated from the other series in the Lake Winnipiseogee basin, and it is the principal component of the several ridges supposed to be repetitions of the Green Mountains. These three groups may be referred to the Laurentian system. Fourth there succeeds an imperfect gneiss, deficient in felspar, 10,000 feet thick, but developed in the highest of the White Mountains, and hence receiving the name of " Montalban." Fifth comes the first of the schistose aggregates, occupying the synclinal positions between the gneisses. As it corresponds closely in strati- graphical and lithological features with that large series first sepa rated from the Laurentian by Sir W. E. Logan upon Lake Huron, the name of Huronian is adopted for its development in New Eng land. The largest terrane borders the Green Mountains through Vermont and Massachusetts. A second commences in the Con necticut basin near Bellows Falls, enlarging very much in the extreme- northern part of New Hampshire. These rocks are 12,000 feet thick. Other terranes of related rocks are to be found in Merrimack, Hillsborough, and Rockingham counties. Veins of copper and gold are wrought in the Huronian. Sixth there follows a succession of schists and slates 11,000 feet thick, whose relations are not well established. Seventh is a series of clay slates, aurifer ous, and 3000 feet thick, referred to the Cambrian. Eighth follows a group of mica schists and limestones, known as the Coos group, and the calciferous mica schist, perhaps 7000 or 8000 feet thick. These are claimed as Silurian by some. Ninth, and last, are fossili- ferous beds of undetermined thickness, as much as 1000 feet, in which occur well-defined Pcntamcrus and Halysites. These show the rock to belong to the Niagara group of the Upper Silurian. The principal localities are at Littleton and Lisbon, at the west base of the White Mountains. The most natural association of these groups is (1) Laurentian, (2) the Montalban, and (3) Huronian, all of which are Eozoic, with an aggregate thickness of 40,000 feet. Next would follow the Huronian and indeterminate groups, reaching 23,000 feet, all believed to antedate Palaeozoic time. Thirdly there remains the supposed Palaeozoic series, 12,000 feet.


Distribution of the rocks over a large part of New England on a scale of about 100 miles to the inch. For convenience they are grouped thus:—(1) granite; (2) Laurentian of New York, and porphyritic gneiss of New England; (3) the later gneissesBethlehem, Lake, and Montalban; (4) Huronian, &c.; (5) Cambrian and Silurian; (6) Carboniferous; (7) Triassic; (8) Quaternary.


Few parts of the country display better evidences of the existence of an ice age than New Hampshire. No extensive rock exposures can be found that do not exhibit marks of scarification. Even Mount Washington has been striated, and boulders weighing 90 lb occur there, which have been brought at least a dozen miles and left 3000 feet higher than their source. The prevailing direction of the striae and transportation of fragments was to the south-east. Local glaciers existed in the decline of the period, leaving well- marked moraines. It was in New Hampshire that the nature of the eskers or kames was first understood in America. A very noted one follows the course of the Connecticut river, from Lyme, N.H., to Windsor, Vt, , a distance of 30 miles. The terraces along the Con necticut, the Merrimack, and other rivers are well shown. Careful measurements indicate that they all slope equally with the descent of the river, and resulted from accumulations of detritus pushed forward when the streams were fed by the waters of the melting ice sheet and stood 200 feet or more higher than at present.

Minerals occurring in sufficiently large quantities to be the object of mining are gold, silver, copper, zinc, lead, arsenic, tin, iron, bis muth, manganese, and molybdenum. Articles used for building purposes occurring largely are granite, coloured porphyries for ornamentation, slate, clays for brick, limestone, and soapstone or steatite. Other useful minerals either obtained directly from the rock or capable of special manufacture are quartz and felspar for glass, mica, plumbago, precious stones, whetstones, copperas, alum, pyrites, titanium, polishing powder, moulding sand, and ochres for paints. There are forty extensive quarries of granite in the State. The stone is very fine grained, of a light grey colour, and is used

largely for obelisks in cemetries. The mineral beryl is very