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country.” If this fact is at all unexpected and different from what has been determined in other cases, which however we do not exactly apprehend, it lies against the present arrangement ; but it is consistent with the arrangement so far as it extends, which makes a portion, at least, of the Trenton rocks equivalent to the Llandeilo series of “ dark-colored calcareous shales.” This will make the Caradoc series and the one here considered its equivalent similar in mineral composition, even sandstone chiefly in both cases.
In the statement of another interesting fact in Silliman's Journal by Mr. Conrad, viz. the identity of the old red sandstone of Europe with the sandstone “near Blossburgh, Tioga county, Pennsylvania," only one fossil is adduced as evidence, “the scales of a fish termed Holoptychus nobilissimus, figured in Murchison's work on the Silurian system.” If this identification is complete, and the old red sandstone, the stumbling-block and reproach of our geology, has a “ local habitation”
name" in our land, “ fortunate” has Mr. C. been to detect it, and sincerely we offer him our congratulations. He says, “this rock not only holds precisely the same place between the coal and the Silurian rocks, and contains the same characteristic fossil, but is the same in color and mineral character, as the old red sandstone of England.” Position and composition concur with organic remains, and give additional confidence that the reproach is removed. But, if so much confidence is attached to one shell, certainly we may trust the evidence of two trilobites that the flags of Llandeilo are a part, though a small part it may be, of the Silurian system in our State, “ thinly deposited” and not "subsequently swept away.” Additional examination will doubtless throw more light upon these formations, and the continuance of the survey for one more season will lead to the satisfactory settlement of the relative place and names of the series. T'he intense interest in fossil remains will give new energy to the geological corps and others. We shall rejoice to see our state palaeontologist, aided by his associates, carry out the work to the full completion of the plan before him.
In respect to the old red sandstone, Mr. Hall, geologist of the fourth district, adopts the same notions as Mr. Conrad. He speaks of it in another place in Pennsylvania, as near to Tioga, and also at Covington; as being more than four hundred feet thick near the former place; as approaching near the bounds of Steuben county and perhaps entering it; as probably identified on the Genesee river, in Allegany county; as characterized by the scales of the fish already mentioned, and containing the remains of another fish whose scale is two inches long and nearly as broad, as well as the bones and teeth of other fish ; and as having been “first described" by Mr. R.C. Taylor of Philadelphia, who "suggested its analogy to the old red sandstone of England.” Rep. p. 393-4, and 453. The honor is enough for two men, the one to have discovered the analogy, and the other to have proved the identity of this sandstone.
The upward limit of the Caradoc series is placed by Mr. Conrad at the lower stratum of the Pentamerus limestone, the lowest layer of the calciferous slate of Eaton. Hence, the ferriferous sand-rock, the argillaceous iron ore, the ferriferous slate, and gray band of Eaton, all so finely presented in the banks of the Genesee, at Rochester, belong to the Caradoc rocks, and are the upper strata of this formation. Next below these is the Niagara sandstone. Many feet above the Pentamerus limestone lies another stratum of shale or marly slate, so like the ferriferous slate below the iron ore that one regrets the separation of the two into different series; and the more so, as the same marly slate occurs continually between the layers of limestone far above. It would seem to be a much more natural division to terminate the Caradoc series upwards with the gray sandstone, the gray band of Eaton, which forms in so many places the upper stratum of the Niagara sandstone. Indeed, it is remarked by Mr. Hall, though he seems to agree generally with the views of the palaeontologist, that “the groups of the Silurian system do not well accord with the natural division of the rocks in New York.” Rep. p. 452. The truth of this admission appears obvious on the face of the report, and proves the vast importance of extending the time to complete the survey, and the wisdom of the legislature in their late act for doing it. In the next year, these and many other points of great interest will doubtless be definitively settled.
Several new species of fossils are described, and some corrections made. Asaphus selenurus and Calymene odontocephalus are now proved to be one from a whole specimen found at Auburn, and the species is hereafter to be known as the Odontocephalus selenurus. C. The name of Gebhard, attached to one of the Schoharie fossils, was richly merited
and well bestowed, as well as of the others who are honored in the same way. We hope more of our geologists will find their names connected in an enduring manner with the discoveries of this brightening period of our geological history. The report
of Dr. Beck on the minerals of the State contemplates them, first, in respect to their geographical distribution, and next, with reference to their existence in the several counties. Both views have much interest; but our attention must be confined chiefly to the former.
The eastern part of the state contains a considerable extent of primitive rocks, and is distinguished for its valuable mines of iron ore, extending over the northern and a considerable portion of the southern, and expanding to a greater extent in the northern counties. A mere reference need be made only to those of the highlands of Columbia county, and of the counties west of lake Champlain. It would seem that the primitive rocks were heaved up at the northern and southern parts and filled with iron ore; while for some distance along the middle of the eastern portion, the primitive rocks have not come to the surface, and along the eastern line of the state the newer of the primitive are thrown up into considerable mountains, while the granitic rocks do not there appear. The county of Orange on the south, and of Hamilton and Franklin on the north, lie on the same meridian, and through these run the mines of magnetic oxyd of iron, extending on either side of the principal line in which the ore appears.
We gave in a previous number some account of the abundance and richness of this ore, both which have augmented before the public eye as the survey has proceeded. Both Mather and Emmons maintain that this ore occurs in veins, and hence the filling up must have been from below by the same power
upheaved the strata and opened the veins. It is true that the veins sometimes lie between the strata, as veins occasionally do; but they lie oblique to the strata, in some part or the whole of their course, often enough to show they are not beds. The rocks in which the magnetic ore is found are all of the primitive kind, or granitic combinations, as gneiss, granitic gneiss, hornblende rock, granite, sienite, and its cognate rocks. These are igneous rocks, and form the first argument for the igneous origin of the ore; the second is the existence of branches extending from the principal vein; the third is the widening of the veins sometimes as they descend; and the fourth is the quantity of the ore, the length and breadth and depth, that is, the magnitude of the mines. Emmons' Rep. p. 299-300.
Passing westward over the granitic rocks and the veins of magnetic iron ore, which cross along the eastern part of St. Lawrence and Jefferson counties, we come, in these counties, upon the mines of specular oxyd of iron. This occurs in two geological positions, either associated with primitive limestone, or between gneiss below and Potsdam sandstone above it. Rep. p. 312. This ore has far more the appearance of lying in beds, or one stratum interposed for some distance between others, and limited to a moderate depth compared with the associated rocks.
While the specular ore lies on the west of the magnetic in the north part of the state, the hematitic ore lies on the east side of the magnetic ore in the southern and eastern section. It lies in beds between the rocks, and often near the junction of the talcose rocks on the east, and the limestone on the west. Beck's Rep. p. 49. This Hematite, the Limonite of authors, extends into the neighboring parts of New England, lying along a line nearly parallel with the general line of the magnetic ore, and reaching far towards the north part of Ver
The same ore is sometimes found on the west side of lake Champlain, associated with the magnetic oxyd, as at the Saxe ore-bed, near Crown Point. Emmons supposes this is altered magnetic ore. Rep. p. 312. Will the chemical combinations admit this explanation? or may not some deposit of the Limonite have taken place on the west side of lake Champlain also ? In Orange county, some Limonite is found. In Europe and our country, these ores belong to the primitive rocks. The argillaceous ore, and the bog ore, and various forms of iron-stone, belong to the other formations, or are deposited above these rocks.
Some minerals, new in our country, seem to have been discovered. Allanite was found in Warwick, Orange county. This is an ore of cereum and iron, mixed with silex, alumine and lime.
Cacoxenite was found in Antwerp, Jefferson county, in an iron mine - originally found in iron mines in Bohemia. It appears to be chiefly a phosphate of iron, and named from its injuring the iron ore.
Stellite of Thompson is in the greenstone at Tappan Slote, Rockland county, and also at Bergen Hill, New Jersey.
Diana, Lewis county, is given as a new locality of tabular spar,
a beautiful mineral of " snow-white color.” Schiller spar, metalloidal diallage, occurs near Carmel, Putnam county, at Brown's quarry.
The Rensselaerite is considered as pyroxenic Steatite. The mineral described by Dr. Emmons under the name of Eupyrchroite, is said to be fibrous phosphate of lime. For this variety, it seems desirable to continue this name, as well as the preceding:
Brown spar or Ankcrite is found at Johnsburgh, in Warren county.
Some minerals, having more interest for some particular reason, are mentioned under the head of the several counties where they occur.
Gypsum is found at Starke, in Herkimer county, and this is its most eastern locality in the state. It is of
fine quality. Rep. p. 69.
A spring of salt water, near York, in Livingston county, is mentioned chiefly for its geographical position, as it has not much strength of salt. It contains muriate of lime as well as muriate of soda, and the tests show a considerable iodine in the
Pearl spar appears in bent and twisted crystals at Rochester, Monroe county, and associated with dodecahedrons of calcareous spar. Rep. p. 77.
In Niagara county, the Lockport minerals lose none of their beauty or interest. The excavations for the enlarged canal have thrown out great abundance of them. To these should be added the various and beautiful and large trilobites which have been given into the hands of the curious as well as into the state cabinet.
In Dutchess county, two and a half miles southeast of Fishkill landing, is a mine of graphite, or black lead, granular and foliated, and pure enough for the ordinary uses of this mineral. Rep. p. 62.
Orange county abounds in common, rare and beautiful minerals; but far the most valuable is the magnetic iron ore situated in the township of Monroe, and of great abundance.
Putnam county also yields many fine minerals, as Albite in large crystals, Brucite, white Coccolite, Chromate of iron. Rep. p. 87.
The county of St. Lawrence abounds also in minerals, though much of it is yet a wilderness, and only partially
NO. XV.VOL. VIII.