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Southern Appalachians, which throw much light upon the probable age of the crystalline rocks of that region. It has long been the tendency of geologists to regard the metamorphic crystalline rocks of the Atlantic coast as certainly pre-Silurian. This has, however, been called in question by the observations of Professor Dana, which go to prove that the limestones and accompanying schists and quartzites of Western New England are all Silurian, and not Huronian nor Laurentian. Professor Bradley now claims the same for the region be has investigated, that is, the western portion of North Carolina, the eastern part of Tennessee, and much of Georgia and Alabama. The evidence upon which the conclusion is based is stratigraphical, and must be studied in detail to be fully understood. The time at which the uplift and metamorphism of this region took place is considered by Professor Bradley to have been post-carboniferous, and it is probably referable to the close of the paleozoic.

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DISCOVERY OF A BED OF NICKEL IN NORWAY. It is announced that a very rich bed of nickel has been re"cently discovered in the forest of Glörud, in Norway. The ore proves to contain 3.59 per cent. of pure metal, an exceptionally large proportion.-13 A, September 4, 1874, 263.

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MAGNETIC SAND IN LABRADOR. It is stated that, within a few years past, large quantities of magnetic iron ore, in sand, have been discovered on the north coast of Labrador, and that Mr. Lamothe, of Montreal, has more recently been engaged in bringing this to public notice. A company was formed, and forges were built at Moisie, which are now in operation, since when other localities have been determined along the north shore, especially at Matashquan, Kegashka, St. John River, and St. Marguerite. Several attempts have been made to purify this sand in a rapid and economical manner, and to make steel from the ore by a direct process, and these problems have now been solved by Professor Larne and Mr. Kizer, of Montreal. An establishment has also been erected at Block Point, between St. John River and Mingan, for the preparation of the sand and its exportation to Swansea. It contains, in the rough state, 30 per cent. of the magnetic iron, and when prepared

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99 per cent. It is expected that thirty tons per day will be furnished at this place. Works for the manufacture of steel from this sand have been established at Quebec, and at Matashquan others are being put up. The ore is said to excel that of New Zealand in richness, and it is probable that before long it will occupy a permanent place in the iron industry.

INTERESTING PHENOMENA OBSERVED IN STONE QUARRIES.

Professor W. H. Niles, of the Boston Institute of Technology, communicates the results of further observations of the peculiar phenomena observed at the stone quarries at Monson, Massachusetts. Similar phenomena have been recorded once before by Professor Johnston, of Middletown, Connecticut, in relation to the sandstone quarries at Portland, in that state. Both these gentlemen concur in the same conclusion, namely, that the strata of sandstone at Portland and the strata of gneiss at Monson are not at the present time perfectly at ease in their ancient beds, but that, in some way, they have received a disposition to change their position slightly; that, in fact, they exist there in a state of conpression, the force with which they tend to expand being so great that it has been known to break apart beds of the thickness of three, four, and five feet, for a distance of 100 feet or more; while in another case one end of a long prismoid of gneiss, being solidly attached to the undisturbed rock, the other end, by its expansion, pushed upward about 10,000 tons of rock. The expansions at Monson take place only in a northerly and southerly direction. The cracks and rents are generally formed slowly, but sometimes suddenly, attended by a loud report similar to that of a slight shock of earthquake, and sometimes by the throwing of stones of considerable size to the distance of several feet.- Proc. Am. Assoc., I., 1873, 156.

the present fresh-wate formation; not explica action. In Shaler has the first of t forded by t! the most is Taking the and abunda look at the the possibil those which stratification action of wat but when the along the sho away.

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CHANGES OF LEVEL ON THE COAST OF MAINE.

For many years there have been reports of changes in the depth of water on the rocks and shoals on the coast of Maine. From a report on this subject to the Superintendent of the Coast Survey, by Professor Shaler, the following facts have been gathered:

The natural indications of changes of level are the remains

country was Third, a seco of local depre try. These s occupy only beds lying w cate a longplace. At 1 again into p

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of marine animals found above the level of high-tide mark; the presence of extensive stratified deposits, at points where fresh-water lakes could have had nothing to do with their formation; and the existence of a characteristic topography not explicable on any other supposition than that of marine action. In his investigation of the coast of Maine, Professor Shaler has not been able to rely to any great extent upon the first of these three natural indications; the evidence afforded by the extensive stratified deposits has been to him the most important, both in its nature and its quantity, Taking the masses of stratified drift as the only acceptable and abundant proof of depression, he considers that we must look at the question of the origin of these bodies of drift and the possibility of their being formed by other agents than those which are at work in the sea. Some slight amount of stratification seems not inconsistent with the theory of the action of water in the formation of extensive sheets of drift; but when the stratified drift is distributed in extensive sheets along the shore, all doubt of marine action may be fairly put away.

The neighborhood of Boston, like the whole country southward to New York, is characterized by having a vast accumulation of drift materials disposed in four distinct formations, each indicating a separate stage of the glacier period; namely, first, massive drift in patches, which are the fragments of a great body of drift of great thickness left by the old glacier ice-sheets. This drift is quite without traces of stratification, and a large part of its pebbles are scarred by glacier scratches. Second, bodies of glacier material rudely distributed by water, the glacier scratches generally worn away from the surface of the pebbles, the whole indicating one or more of the processes by which the re-elevation of the country was effected after the passage of the glacier ice. Third, a secondary glacier series, indicating the recurrence of local depressions after the partial re-elevation of the country. These secondary glaciers in the neighborhood of Boston occupy only the larger stream-beds. Fourth, the rearranged beds lying within a few feet of the present level, which indicate a long-continued rest of the sea, at or near its present place. At this level the life-bearing bodies of drift come again into prominence. Fifth, the extensive mud-beds and

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marshes always colored by the remains of animals and plants, As we go southward from Boston we gradually pass to an area of increased table drift of indistinct stratification, and corresponding to the first of the preceding five geological epochs. At Portland we have decided evidence to show that the depression of the glacier period was 150 feet, or double that of Boston. East of Portland, and covering the country as far as New Brunswick, we have proof of the existence of a set of local glaciers covering the shore, and continuing until the final re-elevation of the land to near its present level. In some remarks upon the origin of the glacier epoch, Professor Shaler has recourse to the theory that our sun is a variable star.- Dem. Bost. Nat. Hist. Soc., II., 1874, 321.

A coal-fiel glish engine southwest of of mountain Mount Oly Kitros, in th about eight area of 2000 coal-field is tains 255,000 vember 14,182

NEW MINING REGION IN NEW MEXICO AND ARIZONA. The Engineering and Mining Journal quotes from a New Mexican paper an account of a very rich and extensive copper region lately opened in New Mexico and Arizona, in the vicinity of the White Mountain Indian Reservation, which from its importance seems likely to eclipse all other mining portions of the Southwest. This results partly from the great amount of ore of unsurpassed richness, and partly from the simple method by which the metal may be reduced. In the region referred to one solid wall of copper ore has been exposed for a distance of 250 feet, and from 10 to 15 feet in height, and of enormous width, yielding 70 per cent. of pure copper. Still larger veins have been found in the neighborhood.-17 D, December 12, 1874, 371.

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PETROLEUM SPRINGS IN NORTH GERMANY. Petroleum springs have lately been discovered in considerable quantity on the Lüneburg Heaths, in Northern Germany. The oil, in clearness, purity, and specific weight, is said to be identical with the American rock-oils, and it is almost without smell of any kind.-13 A, November 14, 1874, 532.

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COAL-MINES IN RUSSIA, Extensive coal-mines have been discovered in the Jekaterinoslaw district, in the lands of the Don Cossacks of Russia. These lie at a depth of about 200 feet, and the yield is so abundant that many thousands of tons have been shipped

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from the port of Taganrog. It is thought that this coal will answer an important purpose in connection with the Suez steam navigation, and in all probability drive out of use in that region the English coal which is now universally employed.—13 A, November 14, 1874, 532.

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COAL-FIELD NEAR DRANISTA. A coal-field has recently been explored by a party of English engineers near Dranista, which is about fifty miles southwest of the town of Salonica, and is inclosed by a range of mountains of crescent shape, commencing on the south at Mount Olympus, and terminating on the north at the bay of Kitros, in the Gulf of Salonica. An aggregate thickness of about eight feet of coal has been found, extending over an area of 2000 acres, although it is thought probable that the coal-field is of much greater extent, and that the basin contains 255,000,000 tons of coal of good quality.-13 A, NOvember 14, 1874, 532.

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GEOLOGY OF COSTA RICA. Professor Gabb, in a communication to the American · Journal of Science, gives some account of the geology of a portion of Costa Rica, which he has been engaged in exploring for some time past, and takes occasion to point out the fact that the highest peak in the country is not the Irazu, as has been generally supposed, but the Pico-Blanco, which he estimates at about 10,200 feet. From its summit large extents of both the Atlantic and Pacific are readily visible.

Geologically the Pico-Blanco is not a volcano, but a culminating point of granite intrusion from below miocene rocks. There is, however, a large mass of true volcanic rock forming the apex, which, nevertheless, is only a dike laid bare by denudation, and does not extend 300 feet below the summit.-4 D, November, 1874, 389.

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FALLING OF ATMOSPHERIC DUST IN NORWAY, MARCH 29 AND

30, 1875, Professor Daubrée communicates to the Academy of Science, in Paris, notes upon certain atmospheric dust which fell in Sweden and Norway in the nights of the 29th and 30th of March, 1875. This was found scattered over the snow,

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