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ward is thus presented to the traveller, especially in regions where man has done little and nature much. Many excellent local delineations have within a few years appeared. Vast magazines of knowledge are garnered in the Transactions of the Geological Societics of London, of Paris, and of other countries. Scientific Journals also abound with like information ; and numerous elementary treatises of value are constantly issuing from the press of this country, as well as from that of America, and many a state in Europe. Even in our cheap,—the cheapest,-publications, the same sort of instruction and delight is often to be found, condensed, popularized, and strikingly illustrated by means of some of the modern inventions in art.

The volume before us is an attractive specimen of the books that have been written on Mineralogy and Geology, and is devoted to a region that is exceedingly rich in respect of both branches of science. The letterpress is accompanied by a coloured map, illustrative of the structure of the peninsula described, and there are also several views given of the scenery.

The book contains the results of the observations of two young men, several years ago, in a field which, for anything we know, is still peculiarly their own, and which they began to clear and to cultivate so far back as 1827, disclosing many of its hidden treasures. They examined accurately and have described minutely, a great mass of facts; avowing honestly but modestly their opinions on some theoretical points in geology.

But these sketches are not a mere dry detail of mineralogical and geological facts, interesting only to those initiated in the sciences. There is to be sure no sweet discourse of birds, to lure us onward, but the enterprising travellers take the reader on board their little vessel, and pilot him around the rocky shores ; now threading the narrow passes among islands and Giant-Causeway looking columns; and now riding on the broad bosom of secluded basins, the great sea-wall of nature rising in immense perpendicular sheets from the deep. We visit with them the numerous capes and towering impending promontories, and gaze on scenery so wildly magnificent, that we almost forget, in the sublimity of conception, that the professed object of the journey relates to earth. They lead us over the Province, and to the mines of copper and iron and coal. We are shown the immense quarries of limestone and plaster. In fact, Nova Scotia, one of the ends of the earth, appears to be the great jewel-shop of the globe ; teeming with agates and cornelian and chalcedony, beautifully spotted like an “onyx eye," and opal, and Scotch pebble, jasper, and rock-crystal of the hue of the topaz, and beautiful amethyst, and brilliant jet. We are particular in mentioning these tempting riches, for the benefit of our fair readers.

The Peninsula of Nova Scotia is marked by three ranges of hills,

which divide its geology into three distinct features. Some of these hills are called mountains, though their elevation does not exceed five hundred feet. The three features in the geology of the Province, are trap, sandstone, and clay-slate. These few formations render the geology of the region remarkably simple. The trap constitutes the North Mountain range, which extends with but one interruption, about a hundred and thirty miles in a direction northeast and south-west, gently curving towards the Bay of Fundy, and filling the space between that bay and Annapolis river. It forms, therefore, the north-western coast of the Province, and its lofty mural precipices present their broad front to the sea, an impregnable barrier against its violence. The trap is sometimes amorphous, sometimes columnar. The prismatic columns present three, five, seven, and nine sides. In some places, as at Isle Haute, the colonnades of trap rise in hexagonal shafts from fifty to a hundred feet above the surface of the water; and these are divided horizontally into blocks, sometimes a foot, but usually less, in diameter, and three times their diameter in length, resting on one another by perfectly flat surfaces. The columns, too, are sometimes curved or twisted in groups.

In no place did our authors observe those articulations of the trappean columns, which are their distinguishing feature in some other localities. At Little River valley, near Digby Neck, the columns present somewhat of the appearance of those of the Giant'sCauseway in Ireland; but even here the columns are imperfectly articulated; and our authors think that the imperfect cup and bail socket, may have been produced by the motion of the horizontally broken columns on each other, caused by the action of the sea-water. It appears too, from their observations, that ordinary causes can produce regular concavities in the top of the shafts of trap. The Nova Scotia trap, then, wants some of the characters of genuine basalt which are present in the most celebrated European localities. In its general structure the trap of Nova Scotia agrees with that of the Hebrides; and in the opinion of our authors is unquestionably basalt. They however prefer to call it "columnar trap," leaving, as they modestly say, " the question of its identity with the basalt of Ireland, to be decided by those better able to do it than ourselves.” There is another feature in the trap of this Province, pointed out as differing remarkably from the basalt of the Giant's-Causeway, and the trap of Europe, as noticed by Daubeny, viz., that its breadth is altogether disproportioned to its length. It is about a hundred and thirty miles Iong, and never exceeds three miles in breath. It seems to be an immense dyke, “thrown up by one sudden and violent eruption from the unfathomable depths of the Bay of Fundy." It will be seen from this quotation, that our authors adopt the igneous origin of trap. They have contributed a considerable number of facts on this interesting question. Visiting the Province with

notions rather verging to Werner's theory, they became, on the trap formation, disciples of Hutton ; and still keeping their minds open to truth, they left the shores of Nova Scotia, impressed with the belief, that the judicious union of the Neptunian and Plutonic theories accounts for the present appearances of our earth's surface.

The trap formation passes into trap-tuff, and this into amygdaloid, which is succeeded by sandstone alternating with shale. Specimens were collected amply illustrating the opinion of Messrs. Jackson and Alger, that shale, red sandstone, and compact trap concur to form trap-tuff

, composed of angular or rounded fragments of the three rocks, which passes by consecutive gradations into perfect amygdaloid, trap-tuff being an intermediate state, necessary to its formation. This opinion appears to be abundantly fortified by their observations. Wherever the junction of shale, red sandstone, and trap occurred, there trap-tuff and amygdaloid were found; and they were not found where this junction did not occur. At Tower Hill nature looks as if she had tried "her 'prentice hand” to make amygdaloid out of shale and sandstone only. She has succeeded so well that she has ventured to put the imitated in the place of the genuine amygdaloid in relation to trap. But the counterfeit is easily detected; for she has filled the cavities of the amygdaloid not with zeolite, but with gypsum, which abounds in the sandstone.

We have not room to mention the numerous rare and interesting minerals found in the trap formation. Without doubt it is one of the “most extensive and fruitful fields for mineralogical and geological research which the known world presents.” Our authors were extremely delighted on finding, for example a gigantic crystal of “Scottish topaz," near Paradise river, which weighed nearly a hundred pounds, was a foot in diameter, and one of whose acuminating planes is twelve inches long. Its splendid display of colours, when the interior is illuminated by strong transmitted light, changing the whole substance into a beautiful transparency, reflecting the varied tints of topaz-yellow and clove-brown, is described with such heartleaping enthusiasm, that we are not at all surprised at the declaration of our authors, " that it is the noblest production which the country has afforded" them.

Sandstone, with slate, forms moderately elevated and rounded hills in Cumberland and part of Hants counties, extending from the Basin of Mines, northerly to the Gulf of St. Lawrence, and eastwardly to Sidney county,--embracing the districts of Colchester and Pictou, and thus forming a large portion of the Province. Its appearance changes very much with its situation, being always of a tile-red colour when near the trap.

The sandstone is itself quarried for grindstones. The best of these are procured at South Joggin, and are wrought on the shore of Cumberland Bay. The deeper dug, the better the stone. The

workman frequently meet in cutting the stone with "bull's eyes," so termed, hard, rounded nodules from one to ten inches in diameter, more compact, and having less argillaceous cement than the surrounding stone. Wherever these “evil eyes” occur, the stone is condemned as useless.

But the sandstone is not only itself a valuable rock; it contains within its bosom rich treasures of plaster, lime, coal, copper, and salt.

Immense beds of plaster occur in the sandstone. Halliburton, in his “ History of Nova Scotia,” says, that 100,000 tons are annually shipped to the United States. These beds are situated all round the shores of the Mines' Basin ; but the largest are at Windsor, and on the banks of the Maran river.

Salt springs occurat various places bordering on the Gulf of St. Lawrence, the richest of which are situated near the river Philip. These have yielded great quantities of salt, by evaporating their briny waters. No rock-salt has been discovered in their vicinity, nor has the sandrock any perceptible salt taste. These facts are important. They enable us to place the sand-rock in the same class, in the opinion of our authors, with that of western New York, “with the red marle of Connybeare and Phillips, which includes the salt mines of England and Poland,” and with that of Connecticut and Hudson rivers.

Very important beds of coal, highly bituminous, occur in the village of New Glasgow, near East river. The coal is included between strata of sandstone, covered by decayed blackish shale. In its character it approaches the Newcastle coal. Vast quantities of this fuel are shipped to the United States. The sandstone contains one other important mineral, viz, copper, found in beds between the strata, near the Carriboo river, in the township of New Philadelphia, where the river empties itself into the Gulf of St. Lawrence. Masses of vitreous copper ore, invested with delicate fibres of blue and green carbonate of the metals, occur at this locality. The miners from Cornwall who were exploring the mine, called the ore grey copper. Messrs. Jackson and Alger analysed it, and found it to be the vitreous copper, an ore much more valuable than grey.

The last of the great formations of Nova Scotia is Clay-slate, of which the South Mountain range is composed, and which, stretching from Pictou District on the east to the opposite western coast, covers nearly one half of the province, presenting everywhere a unigeological character. This formation frequently alternates with quartz rock, which seems to have been mistaken by some other observers in this region for primitive trap. The slate is extensively quarried at Rawdon, both for writing and for roofing slate, and in other places for building materials. Dykes of trap porphyry interrupt the strata of slate in two places, cutting them at right angles, and completely intercepting a great bed of iron ore, which runs from

one extremity of the slate formation to the other, continuous and parallel with its strata. This is the most interesting feature in the slate formation. The ore bed is from ten to sixteen feet wide, and shows a very remarkable difference in its character, accordingly as it approaches or recedes from the trap formation. At Pictou, remote from trap, it is in the state of peroxide, neither metalic in lustre nor magnetic, yielding about fifty per cent. of metal. At Clement's mine, the western terminus of the bed, and nearer the trap, the ore is in the state of protoxide, glistening with metallic lustre; and it is highly magnetic, yielding in the furnace somewhat less than sixtyfive per cent of strong soft iron. Our authors discuss the question relating to these different states of the ore. Why is it a peroxide and non-magnetic at Pictou, and a magnetic protoxide at Clements? They find their answer in heat; this, they are of opinion, has caused the variation of character, and they find the source of this heat in the igneous origin of trap.

Organic remains abound in the slate and in the ore-bed of iron. Both contain beautifully perfect remains of shells. The coal measures present the vegetable remains common to that formation, and numerous remains of culmiferous plants, some of which are of gigantic size.

The geological map which accompanies the volume serves to render the description satisfactorily plain; while the lithographic views not only convey an idea of the formations of the country, but of its picturesque and romantic features.

Art. XI.-A History of the Vegetable Kingdom. By Wm. RHIND.

. 3 Parts. Glasgow : Blackie and Co. Glasgow! Alma Mater! we like you well. And if we had opportunity to return to the green, we should once more luxuriate over thoughts, feelings, and speculations that are nearly fifty years old. But botany-vegetable physiology-practical and pleasant gardening! Where shall we look for these combined blessings in higher display than in William Rhind's “Vegetable Kingdom?” Because, you must observe, that Rhind is not merely a student scientifical, but a naturalist, in the right sense of the word,—that is, a philosopher who draws his ideas from experience in the paths that our eyes love to dwell upon—the velvet green and the mountain swarth of Old England. Still, with a natural leaning towards the North, we wish to express one idea or two, and they merely amount to assertions, viz., -How comes it, we ask, that Scotch gardeners stand so high in the scale of their art

in the decorative little sphere of farming, as it may be called ?

The first answer is,--that during the predominance of the Romish

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