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in New Hampshire appear to be the most lofty, and their height is somewhat more than 6000 feet above the level of the
The most elevated parts, as well as the greatest mass of this range, consist of primitive rocks; but, as it approaches the Hudson river, and where it traverses the State of New Jersey, these rocks decrease in height and breadth. In Pensylvania and Maryland, the prin itive rocks occur sparingly, the highest parts of the range consisting of transition rocks, with some interven, ing valleys of secondary. In Virginia, the primitive rocks ingrease in breadth and in height; and they form the greatest mass, as well as the most elevated points, of the
of mountains in the States of North Carolina and Georgia, where it takes a more westerly direction.
• Besides this great range, there is an extensive district, occupied by primitive rocks on the west side of Lake Champlain, having that Lake, and Lake George for a boundary on the east, joining the prie mitive rocks in Canada to the north and north-west, and following a line from the Thousand Islands in St Lawrence, running nearly parallel to the Mohawk river, until it meets Lake George on the southwest. These primitive rocks run across the Mohawk at the Little Falls, and near Johnstown on the Mohawk, where they are covered by limestone ; they occupy all the mountainous country between Lake Champlain, the St Lawrence, and Lake Ontario.' p. 38.
. From near Kingston on Lake Ontario, to some distance below Quebec, the country is principally primitive; and, from all the information I could collect, that great mass of continent lying to the north of the 46th degree of latitude, for a considerable distance to the west, consists mostly of the same formation : from which it is probable, that on this continent, as well as in Europe and Asia, the Northern regions are principally occupied by the primitive formation.'
Throughout the greatest part of the northern and north-eastern States, the sea washes the primary rocks; but at Long Island there commences an alluvial formation, which, increasing in breadth as at stretches southward, covers a great part of both the Carolinas and Georgia, and almost the whole of the two Floridas and Lower Louisiana. This vast alluvial formation is bounded on the east by the ocean, and by a line commencing at the eastern end of Long Island and passing through Philadelphia, Washington, Richmond in Virginia, Halifax in North Carolina, Columbia in South Carolina, Augusta on the Savannal, and thence to Natchez on the Mississippi. The tide water ends in all the rivers from tlie Mississippi to the Roanoke at the distance of from thirty to one hundred and twenty miles from the western limits of the alluvial formation; from the Roanoke to the Delaware, the tide penetrates through the alluvial, and is stopped by the primitive rocks. In all the northern and east
ern rivers, the tide runs a small distance into the primitive formations. In the Southern States the alluvial formation is elevated considerably above the level of the sea; but as it approaches the north, it rises very little above it.
On the western side of the great range of mountains, there is a long narrow zone of transition rocks, beginning on the eastern side of Lake Champlain, and extending in an undulating line in a south-westerly direction, to a point between the Alabama and Tombigbee rivers, in latitude about 34 N. and longitude about 85 W. It is generally broadest where the primitive formation is narrowest, and vice versa ; and runs from twenty to a hundred miles in breadth.
On the north-west of those transition rocks commences an immense region of secondary rocks, extending beyond Lake Superior to the north, and some hundred miles beyond the Mississippi to the west, not far distant from the foot of the Stony Mountains, forming an area of about fifteen hundred miles from east to west, and about twelve hundred miles from north to south.
The Volcanic Fires which constitute so grand a feature in the Geological History of South America, have not extended their dominion to the northern continent, nor have any productions been discovered which indicate that volcanoes have at any time existed there.
The direction of the stratification in the primitive rocks runs nearly north and south, eastward of the State of New York, with an eastern dip. In the State of New York and to the south and west, the stratification runs nearly NE. and SW., the dip still continuing to the east. The dip is generally at a greater angle than 45°, and sometimes the strata are almost vertical. The direction of the strata in the Transition rocks is also from north and south to north-east and south-west, dipping generally to the north-west, at an angle in most places under 45°. On the edge of the primitive rocks, there is a deviation in some places from this general rule; the dip being, for a short distance, to the south-east. The outline of the mountains of this formation is almost a straight line, with few interruptions, bounding long parallel ridges of nearly the same height, declining gently towards the side where the stratification dips from the horizon, and more precipitous on the opposite side where the edge of the stratum breaks out to the day.
Of the primitive rocks Granite forms but a small part; but it is found both on the tops of the mountains and in the plains.
There are many varieties of it, in regard to the size of its constituent parts; and it is occasionally mixed with hornblende.
This latter variety, by some geologists, would be called a Sienite; but its geological position is the same as the compound of quartz felspar and mica, which, by the same geologists, is considered as the only true primitive granite. In mentioning this variety, Mr Maclure remarks, that
"The rounded globules of felspar and hornblende found in the great masses of granite of the Alps, in Cornwall and in this country, could not be distinguished, in hand specimens, from the Sienite of Werner, though the one is placed in the Wernerian system as the oldest, and the other among the newest of the primitive rocks.'
The granite generally divides into rhomboidal masses, and, except in some very small-grained varieties, there is no appearance of stratification. It is frequently so far decomposed as to have lost the adhesion of its particles, to the depth of 30 or 40 feet below the furface; each crystal is in its place, and looks as. if it were solid; but when
it falls into sand. Gneiss extends over a half of the primitive formation. It includes in a great many places beds from three to three hundred feet thick, of a very large-grained granite, which run in the same direction, and dip as the gneiss does. These beds are mixed, and alternate occasionally in the same gneiss, with primitive limestone, beds of hornblende and hornblende slate, serpentine, felspar rocks, and magnetic iron ore. In some places the gneiss contains so much mica as to run into mica slate; in others, large nodules of quartz or felspar, and, in others, hornblende takes the place of mica.
· Though the primitive formation contains all the variety of primitive rocks found in the mountains of Europe, yet neither their relative situation in the order of succession, or their relative heights in the range of mountains, correspond with what has been observed in Europe. The order of succession from the Clay slate to the Granite, as well as the gradual diminishing height of the strata, from the granite through the gneiss, miça slate, hornblende rocks, down to the clay slate, is often so inverted and mixed, as to render the arrangement of any regular series impracticable.' p. 16.
Within the limits of what may be termed the primitive country, there are found several partial and detached formations of the transition and secondary rocks. A transition formation occupies nearly the whole of Rhode Island, and runs from Rhode Island to Boston, fifteen miles broad. There is a range of se condary rocks, extending, with some intervals, from the Connecticut to the Rappahannock rivers, a distance of nearly four hundred miles; and in width, generally from fifteen to twentyfive miles. It appears to belong to the old red sandstone formation of Werner. A formation of transition rocks runs nearly south-west from the Delaware to the Yadkin river, from two
to fifteen miles broad, consisting of beds of blue, grey, red, and white small-grained limestone, alternating with beds of greywacke and greywacke slate, quartzose granular rocks, and a great variety of the transition class. Much of this limestone contains so much small-grained sand, as to resemble a dolomite; and, in many places, considerable beds of fine-grained white marble, fit for the statuary, occur. About ten or twelve miles west of Richmond in Virginia, there is a coal formation, lying upon, and surrounded by primitive rocks. It is situated in an oblong basin, from twenty to twenty-five miles long, and about ten miles wide, having the whitish freestone, slaty clay, &c. with vegetable impressions, as well as most of the other attendants of that formation.
Great varieties of mineral substances are found in the primitive formation; and, from the number already found, in proportion to the limited researches that have been made, it is probable, that, in so great an extent of rocks of a crystalline structure, almost
mineral substance discovered in similar situations elsewhere, will be found in this country. Metallic substances are found in considerable abundance in the primitive rocks-iron, copper, manganese and cobalt. The general nature of metallic repositories in this formation appears to be in beds, disseminated through the rock, or in lying masses. Veins to any great extent have not been discovered in any part of this formation,
« The transition rocks consist of a small-grained limestone, of all the shades of colour, from white to dark blue, in some places intimately mixed with strata of greywacke-slate ; lime spar in veins and disseminated; in many places an intermixture of small-grained particles, so as to put on the appearance of a sandstone, with excess of lime cement. This occurs in beds from fifty to five thousand feet in width, alternating with greywacke and greywacke-slate. Near the borders of the primitive is found a siliceous aggregate, having particles of a light blue colour, from the size of a pin's head to an egg, disseminated in some places in a cement of a slaty texture, and in others in a quartzose cement; a fine sandstone, cemented with quartz in large masses, often of a slaty texture, with small detached scales of mica intervening; a rock not far from the borders of the primitive, partaking both of the porphyry and the greywacke, having both felspar crystals and rounded pebbles in it, with a cement of a kind of dull chlorite slate in excess; another, though rarer, with pebbles and felspar crystals, in a compact petrosiliceous cement, and a great variety of other rocks, which, from their composition and situation, cannot be classed but with the transition.
• The limestone, greywacke, and greywacke-slate, generally occupy the valleys, and the quartzy aggregates the ridges. There are many and extensive caves in the limestone, where the bones of various ani. mals are found.
• Beds of coal blende, or anthracite, accompanied by alum slate and black cha!k, have been discovered in this formation, on Rhode Island, the Lehigh and Susquehannah rivers, and a large body of alum slate on Jackson's river, Virginia; many powerful veins of the sulphate of barytes cross it in different places. '- Iron and lead have as yet been the principal metals found in this formation; the lead in the form of Galena, in clusters, or what the Germans call Stockwerk, as at the lead mines on New river, Wyeth county, Virginia ; the iron disseminated in pyrites, hematitic and magnetic iron ; or in beds; and considerable quantities of the sparry iron ore in beds, and disseminated in the limestone.' p. 51.
The immense basin to the west of the Alleghany mountains, through which so many mighty rivers flow, is wholly composed of secondary rocks, without having their continuity interrupted by any other formation, except the alluvial deposites on the banks of the large rivers. The stratification is almost perfectly horizontal.
• Immense beds of limestone, of all the shades, from a light blue to a black, intercepted in some places by extensive tracts of sandstone, and other secondary aggregates, appear to constitute the foundation of this formation, on which reposes the great and valuable coal formation, which extends from the head waters of the Ohio in Pen. sylvania, with some interruption, all the way to the waters of the Tombigbee, accompanied by the usual attendants, slaty clay and freestone, with vegetable impressions, &c.; but, in no instance that I have seen or heard of, covered by, or alternating with, any rock resembling basalt; or indeed any of those called the newest floetz trap formation.
• The limestone of this formation contains irregular pieces in nodules and bands, of a kind of black flint (like what is called Chert in England), scattered in all forms and directions, often resembling the limestone in colour, in which case it is with difficulty they can be distinguished; they abound on the banks of Lake Erie, on the banks of St Lawrence, whence it runs from Lake Erie, and, generally, through the whole stratification of limestone.
Along the south-east boundaries, not far from the transition, a rock salt and gypsum formation has been found. On the north fork of the Holstein river, not far from Abingdon, Virginia, and on the same line south-west from that, in Greene county and Pigeon river, state of Tennessee, it is said quantities of gypsum have been discovered; from which, and the quantities of salt licks and salt springs found in the same range, so far north as lake Oneida, there is some probability that this formation is upon the same great scale that almost all the other formations have been found on this continent,-át least rational analogy supports the supposition; and we may hope one day to find an abundance of those two most useful substances,