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which are generally found mixed, or near each other, in all countries that have hitherto been carefully examined.' p. 35.
• There are a great many detached masses of granite and sienite, scattered over the surface of that part of the basin which lies to the north of the Ohio river, but runs to the south; from which it is probable that they have come from the north, perhaps from the primitive mountains north of the great lakes.
The alluvial country, eastward of the Alleghany mountains, is composed of beds of sand, gravel and clay, differing in their nature, according to that of the adjoining rocks, from the disintegration of which they have been produced. They contain both animal and vegetable remains, which are found to the depth of nearly
a hundred feet below the surface. Considerable banks of shells, mostly bivalves, run parallel to the coast, imbedded frequently in a soft clay or mud, resembling that in which the living animal is now found on the sea shore, and which makes the supposition probable that they are of the same species.
* There is also a bank of sheli limestone beginning in North Carolina, parallel to, and within the distance of from twenty to thirty miles of the edge of the primitive, through South Carolina, Georgia, and part of the Mississippi territory. In some places this bank is soft, with a large proportion of clay; in others hard, with a sufficiency of the calcareous matter to be burnt for lime. Large fields of the same formation are found near Cape Florida, and extending some distance along the coast of the bay of Mexico. In some places the calcareous matter of the shells has been washed away, and a deposite of siliceous flint, in which they were imbedded, is left, forming a porous flinty rock, which is used with advantage for millstones.
• In the alluvial of New Jersey, about ten or twenty feet under the surface, there is a kind of greenish blue marl, which they use as manure, in which they find shells, as the Ammonite, Belemnite, Ovulite, Cama, Ostrea, Terebratula, &c. Most of these shells are similar to those found in the limestone and greywacke of the transition, and equally resemble those found in such abundance in the secondary horizontal limestone and sandstone ; from which it would follow, that the different classes of rocks on the Continent cannot be distinguished by their shells, though the different strata of the same class may
be discovered and known by the arrangement of the shells found in them.
• Considerable deposites of bog iron ore occupy the lower situa. tions; and many of the more elevated and dividing ridges between the rivers are crowned with a sandstone and puddingstone, the cement of which is bog iron ore.'
From the interesting and instructive sketch which Mr Maclure has given of the Geology of so large a portion of the continent of North America, we obtain an important addition to the evidence we already possess in proof of the uniformity of structure which seems to prevail over the whole surface of our globe. No new formation has been discovered, nor any predominant rock which this experienced geologist has had any difficulty in recognising as identical with what he had seen in every part of the Continent of Europe. There are, however, two remarkable peculiarities in the country our author has described, which distinguish it from any other of the same extent with which we are acquainted. These are, the very rare occurrence of the trap-rocks and porphyries, and the great extent to which the same series of rocks stretch, without undergoing any change in the uniformity of their composition, and without any disturbance in the regularity of their stratification. When we combine this undisturbed state of the strata with the absence of a class of rocks which are almost invariably accompanied, in other countries, by a dislocation and confusion of the adjoining strata, it must be considered an argument of considerable
weight in support of that theory of the origin of the trap-rocks, which supposes them to have been ejected from below, and to have broken up and insinuated themselves among the superincumbent strata. But this is a point of theory supported by so great a body of evidence, that we presume there is now no geologist so bigotted to the aqueous creed as to refuse his assent to it,
The Elementary Treatise of Mr Cleaveland is a work of cone siderable merit. He has derived his materials, as he informs us, chiefly from the works of Hauy, Brochant, Brongniart, Lucas, Kirwan, and Jameson ; but he has adopted Brongniart as his model; and, in doing so, we think he has followed the most judicious and most useful of all the mineralogical writers who have preceded him. We entirely concur in the following remarks on the Treatise of Brongniart by the author in his Preface.
Many of the writers of the French and German schools appear te have indulged an undue attachment to their favourite and peculiar sy& tem, and have hereby been prevented from receiving mutual benefit; the one being unwilling to adopt what is really excellent in the other. But it is believed, that the more valuable parts of the two system, may be incorporated, or, in other words, that the peculiar descriptive language of the one may, in a certain degree, be united to the accurate and scientific arrangement of the other. This union of dee scriptive language and scientific arrangement has been effected with good success by Brongniart, in his System of Mineralogy-an eleinentary work, which seems better adapted both to interest and in. struct, than any which has hitherto appeared.'
Although this book is necessarily compiled, in a great degree, from the writings of others, it contains much valuable in formation respecting the mineral productions of the United States. It is to this part of the work that we shall confine our remarks; and we feel disposed, for the sake of our general readers, to dwell chiefly on the information Mr Cleaveland conveys respecting those mineral substances that are connected with the advancement of that active and enterprising people in wealtlı and political importance, rather than upon the rarer productions, which are only interesting to the mineralogist.
There is one merit of Mr Cleaveland's book that ought not to pass unnoticed; we mean the forın in which it is published. It is printed upon excellent paper, with a neat and perfectly distinct small type; and the same matter is contained in one volume, which, in England, would have been scattered over the surface of three. We should be glad to see it reprinted exactly upon the plan of the original ; and we have no doubt that it would be found the most useful work on mineralogy in our language.
Coal exists in several parts of the United States in great abundance. We have already spoken of the vast series of coal strata westward of the Alleghany range, and of an extensive coal formation near Richmond in Virginia. In Pensylvania, it is found on the west branch of the Susquehannah; in various places west of that branch; also on the Juniata, and on the waters of the Alleghany, and Monongahela. In Connecticut, a coal formation, commencing at Newhaven, crosses Connecticut river at Middletown, and, embracing a width of several miles on each side of the river, extends to some distance above Northampton, in Massachusets. There are also indications of coal in the States of New York and New Jersey. In Rhode Island, anthracite is found, accompanied by argillaceous sandstone, shale with vegetable impressions, &c. similar to the usual series of coal strata. The coal at Middletown, in Connecticut, is accompanied by a shale which is highly bituminous, and burns with a bright flame.
“ It abounds with very distinct and perfect impressions of fish, sometimes a foot or two in length; the head, fins and scales, being perfectly distinguishable. A single specimen sometimes presents parts of three or four fish, lying in different directions, and between different layers. The fish are sometimes contorted, and almost doubled. Their colour, sometimes grey, is usually black; and the fins and scales appear to be converted into coal. The same shale contains impressions of vegetables, sometimes converted into pyrites.
Neither Mr Cleaveland nor Mr Maclure give us any information respecting the extent to which the coal has been wrought in any of the numerous places where it has been found, or the thickness of the seams. A scarcity of wood for fuel must be felt before coal will be sought after with much spirit; and there is probably still wanting in the United States that profusion of capital which can be risked in the uncertain operations of mining.
Iron is found in the United States in a great variety of forms, and is worked to a considerable extent. In the
In the year 1810, there were five hundred and thirty furnaces, forges, and bloomeries, in the United States, sixty-nine of which were in the State of New York; and the iron manufactured at Ancram, New York, is said to be superior, for many purposes, to the Russian and Swedish iron. It is made from a hematitic brown oxide. Mr Maclure informs us, that there is a bed of magnetic iron ore, from eight to twelve feet thick, wrought in Franconia, near the White Hills, New Hampshire; that there is a similar bed in the direction of the stratification, six miles north-east of Philipstown, on the Hudson river; and, still following the direction of the stratification, that the same ore occupies a bed nearly of the same thickness at Ringwood, Mount Pleasant, and Suckusamny, in New Jersey; losing itself, as it approaches the end of the primitive ridge, near Blackwater-a range of nearly three hundred miles. This immense deposite of iron ore is contained in gneiss, and is accompanied by garnet, epidote, and hornblende. In the State of New York, magnetic iron ore is found in immense quantities on the west side of Lake Champlain, in granitic mountains. The ore is in beds, from one to twenty feet in thickness, and generally unmixed with foreign substances : large beds of this ore extend, with little interruption, from Canada to the neighbourhood of New York. Clay ironstone is met with in considerable quantities. In Maryland, there are extensive beds of it three miles SW. of Baltimore, composed of nodules formed by concentric layers. Bog iron ore occurs in such abundance in many places, as to be smelted to a great
Copper in the native state, and most of its ores, have been found in different parts of the United States; but there are no mines of this metal except in New Jersey, and these do not appear to be worked with much success.
Lead has been discovered in a great variety of forms; and there are several extensive mines of it. In Upper Louisiana, at St Genevieve, on the western bank of the Mississippi, there are about ten mines. The ore, which is a sulphuret, is found in detached masses of from one to five hundred pounds, in alluvial deposites of gravel and clay, immediately under the soil ; and sometimes in veins or beds, in limestone. One of the mines produces annually about 245 tons of ore, yielding 66} per cent. There are mines also at Perkicinen, in Pensylvania, 24 miles from Philadelphia. The ore is chiefly a sulphuret; but it is accompanied by the carbonate, phosphate, and molybdate. In Massachusets, there is a vein of galena, traversing primitive rocks, six or eight feet wide, and extending twenty miles from Montgomery to Hatfield. The ore affords from 50 to 60 per cent. of lead.
Geld has only been found in North Carolina. It occurs in grains or small masses, in alluvial earths, and chiefly in the gravelly beds of broeks, in the dry season; and one mass was found weighing 28 lib. In 1810, upwards of 1340 ounces of this gold, equal in value to 24,689 dollars, had been received at the mint of the United States.
Native silver, in small quantities, is met with at different places, but in no other form. Mercury and tin have not been found. Cobalt occurs near Middletown, in Connecticut; and a mine of it was at one time worked. Manganese and antimony are found in several situations. Sulphuret of zinc is found in considerable quantity in Maryland, Pensylvania, New Jersey, and Massachusets. In New Jersey, a new variety of this nietal has been discovered, in such abundance, that it promises to be a very valuable acquisition to the United States. . It is a red oxide, composed, of zinc 76, oxigen 16, oxides of manganese and iron 8. It is reduced without difficulty to the metallic state.
The chromate of iron, both crystallized and amorphous, uccurs in different situations; particularly near Baltimore, and at Hoboken, in New Jersey. This mineral is employed to furnish the chromic acid, which, when united with the oxide of lead, forms chromate of lead-a very beautiful yellow pigment, of which there is a manufactory at Philadelphia. It is sold under the name of chromic yellow, and is employed for painting furniture, carriages, &c.
In the former part of this article, we have noticed the vast extent of limestone of different species that is spread over the United States. Mr Cleaveland enumerates several varieties of the primitive limestones in the Eastern States, which are used as marble in ornamental architecture and in sculpture; but he remarks, that the state of the arts has not yet caused them to be extensively quarried, or even sufficiently explored. Some of the Vermont marbles are as white as the Carrara, with a grain intermediate between that of the Carrara and Parian marbles. At Middlebury, in Vermont, during the years 1809 and 1810, 20,000 feet of slabs were cut by one mill, containing 65 saws;