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by an editorial vindication of the author of the Essay, and the draw. backs on the plea of misapprehension and severity.' I had no motive but to correct error and elicit truth, and with the convictions of duty and sense of responsibility under which I write for the press, had the whole array of great names to whom he refers been marshalled with him in solid column, I should not have shrunk from the fearless and conscientious performance of my duty. And upon a review of my 'Strictures' and all the garbling and misrepresentation of which I now complain, together with the personalities to which I have been subjected, from the author of the Essay, I cannot regret a single step I have taken, a single criticism I have made. What I have written, I have written.'

If our controversy shall prevent the future agitation of the question, and should the epitaph be written for theological seminaries among the Methodists, I shall rejoice to have contributed in any way to a burial, from which I pray there may never be a resurrection.

DAVID M. REESE.

From the Salem (Massachusetts) Landmark.

GEOLOGY.

MR. SILLIMAN commenced his fourth lecture on Friday evening of last week, with some additional remarks on trap rocks. He said the difficulty in regard to their formation might be explained by the supposition that they had been protruded from the bottom of the ocean. In the first chapter of Genesis it is stated that the earth was once à liquid mass: The Spirit of God moved upon the face of the waters; and at a subsequent period the dry land is said to have appeared.Aside from the authority of Scripture, the geologist, from a simple examination of the appearances of the earth, would infer that it had been submerged; or in other words, that there had been a deluge. Had not the trap rocks been melted under an enormous superincumbent pressure like that of the ocean, they would exhibit a very different appearance from their present one; their surface would have been infla ted, intumescent, and scoriated.

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Marked changes are produced by the trap on the rocks through which it passes. It turns coal into coke or charcoal; it crystalizes sulphur; and turns clay sandstone into brick or jasper. The lecturer described columns of this rock, which are about two miles from the city of Hartford, Connecticut. These columns rest on sandstone; the junction they are inflated just as their whole surface would have been, had they not been melted under water. Mr. Silliman said it was impossible to explain the facts connected with the trap rock, but on the principle of fire that had once rendered it liquid.

He then proceeded to the history of the granite, the fundamental rock of the globe. With Broigniart's map he exhibited the different layers of rock as they exist in the crust of the earth. He illustrated the difference between stratified and unstratified rocks by reference to two loaves of bread, the one being cut into slices representing the stratified, and the other not cut representing the unstratified rocks.The origin of this is from fire and water. It was water that made the

layers. There were mechanical and chemical influences in these formations. There was crystalization, which is the result of cohesion from chemical solution. Some of the rocks were entirely subject to the chemical process; others to the mechanical; and others still to the two powers combined.

Granite is made up of three substances, viz. quartz, consisting of silex, one of the most imperishable things in our world; felspar, not quite so hard as quartz, and composed of two-thirds silex, and the remainder alumine and alkali. Felspar is found in great abundance in Chester, Pennsylvania, and is manufactured into porcelain. The third substance entering into the formation of granite, is mica, or ising-glass, unlike all other minerals, in being perfectly elastic. Of the three substances constituting granite, quartz is gray, felspar white, and mica black.

The ancients were well acquainted with granite. Pompey's Pillar and Cleopatra's Needle were made of red granite. To determine whether a bed of granite will be durable for use, it is only necessary to see whether it has endured the effects of time. If it has not been decomposed where it has been exposed to the action of the weather, then it may be concluded it will prove good for building. The Quincy quarry is Sienite granite. When mica is wanting in granite it is called Sienite.

The position of granite is below all other rocks, though it occasionally rises above them all. Mount Blanc, Mount Washington, and the Rocky Mountains are granite. This rock is entirely crystalized. It is sometimes the surface rock, as any rock may be.

No animal or vegetable remains are found in the granite, trap, serpentine, porphyry, or soapstone rocks. Hence they are called primitive, as they are believed to have been formed before there were any animals or vegetables. To the granite family belong gniess and mica slate. Gniess is an admirable rock for architecture, various in its appearance, lying next to granite, and the first that is stratified. Mica slate is of the form of the leaves of a book, and is easily split, and is destitute of felspar. In this rock are found gems known by the names of beryl and garnet. Granite, gneiss, and mica-slate are the foundation of the world. Most of the rocks in New-England belong to the granite family.

Upon these are piled the common slate, of which the best for use should be distinguished by thinness, firmness, smoothness, and the absence of foreign minerals. The best common slate is from Wales.— There is also the chloride slate, the hornblend slate, the hone slate, and the talcose slate, which is soft and easily broken; and there is also the magnesia slate which some famishing inhabitants of savage countries are said to eat. Iron is found in the slate at Williamsburgh in this

state.

On closing his description of the slate, Mr. Silliman said he had gone through with the history of the primitive rocks, so called, because they are presumed to have been formed anterior to the other rocks.As to the theory of their formation, he said that fire had had the principal agency, that geologists considered them as the undoubted product of fire; though the slaty and crystalized rocks should be regarded as the joint production of fire and water.

A part of the primary series is the statuary marble, or primary limestone, which is most beautifully deposited in New-England, especially in Lanesborough and Sheffield, though it is very rare in old England. Beds of it are elegantly situated between the strata of gneiss and mica slate. Being in company with the primary rocks it is called primary, though composed of different materials from granite, having calcareous lime, and carbonic acid.

Serpentine rock is so called from having the appearance of the back of a serpent. This rock is applied to cutlery by Mr. Ames of Springfield, in a most beautiful and durable way. It is very different from limestone, though frequently associated with it; it consists of silex and magnesia. In union with this asbestos, a fibrous, incombustible substance, is often found. Asbestos was used by the ancients for the preservation of the ashes of the burned bodies of their departed relatives; and it is likewise used by moderns. It would make excellent dresses for firemen. Verd Antique marble is made up of limestone and serpentine. There is a quarry of this near New-Haven. Soapstone forms beds in mica-slate; it is magnesian, consisting chiefly of talc, and is most valuable for enduring fire. There is a large bed of it in Groton.

In his fifth lecture on Monday evening of this week, Mr. Silliman mentioned that quartz was often crystalized, and was of all sizes; and had doubtless once been soluble; and indeed had been found actually melted. He said there was abundance of porphyritic granite and trap on Cape Ann, as he had ascertained by a ride thither the Saturday before. He advised there should be added to the splendid East India Museum at Salem geological specimens. Porcelain clay was described as made of decomposed felspar.

The Beverly rock the lecturer represented as remarkably interesting. It is near the bridge; it has a basis of sienite, and dikes of trap five feet wide, with veins of felspar and quartz crossing each other; not blended but distinct. It is manifestly the effect of fire.

The professor considered geology the grandest science next after astronomy; the former having one advantage over the latter, in presenting objects that can be handled, and seen with perfect distinctness.

He was aware, he said, that he made a great demand on the confidence of his audience; but he wished them to remember that He who made the world had no limits of time or space; and therefore there need be no trouble about time in the first formation of the globe. He was addressing those who believed in God. If this belief were set aside, he would relinquish all farther examination into the structure of the world, and be for ever silent on every subject of science.

The man

who disbelieved in God, he regarded not as a rational being, but as a mad man.

He said that quartz frequently formed a rock by itself; there was the granular quartz, which is in grains, and will not crack by heat.Granite is sometimes cracked, but never stratified. There are masses

of decomposed granite and sienite on Cape Ann. Rocks lying upon granite are stratified. In these are found fossils, which are the remains of plants and animals. The inference is, that there were no animals nor plants in existence when the rocks, having no such remains, were formed, which rocks have already been descri

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Fire as well as water effects

bed, and are all more or less crystalized. crystalization; and the process has been seen to go on in volcanoes. It has been objected that lime could not have been ignited, because in that case it would have been turned into quick lime. Sir James Hall, the father of the famous Captain Basil Hall, set aside this objection by actual experiment. He found that marble could be heated in a gun barrel without losing its carbonic acid. A similar experiment, with a similar result, has been performed on trap rock.

Professor Silliman said he had now come to a period in our world where marks of violence were visible. By movement in the water, rough, angular masses of rock are made smooth and round; and these smooth, round substances are found in the interior of continents. The shores of New-Holland are strown with the topaz, a mineral next to the diamond in hardness. The original materials were broken off and deposited by gravity. Thus jasper is discovered cemented by a paste of quartz. Such deposites must have come in after the primary rocks. They are remarkable for their elevations; are found on the Catskill mountains. After being formed, they must have been raised by internal fire. The pudding stone, or the conglomerate, is traced high up the Alps.

The first evidence that the formation of the globe was progressive, is the fact, that down in very deep rocks are fossils, the remains of strange animals, embedded in solid masses. The trilobite, an animal that once swam in the water, may be seen in abundance at Trenton Falls. Almost all animals found in rocks have become extinct. It was the will of our Creator that the earth should be gradually prepared for the animals that were to live upon it. There are traces of fossils even in the pudding stone.

The transition rocks are those which appear to be passing from one state into another. In these are vast numbers of animals now extinct. The early corals are remarkable. There are the living corals in the seas of all warm climates. In the production of the coral, the animal collects the lime from the ocean. These productions are of every variety of form. The chain coral is found in the interior of our own country. It is found in fields, in mountains, and in rocks; some corals are silex, and some lime. These works of animals are sometimes built up into high mountains. In the southern seas there are reefs of coral a thousand miles long. They are first erected as walls against the wind. The animal never works above the water; he brings up his establishment to the surface and there leaves it; but birds and plants may add to its elevation; still it must have been fire beneath that has raised them to the height which in many instances they have attained. The professor said there was good reason to believe the bottom of the ocean to be similar to the surface of the earth; and as corals form parts of our mountains, the inference is, that this continent was once under the ocean.

In limestone are vast caverns. The Mammoth Cave, in Kentucky, has been explored to the extent of ten miles without coming to any limits. Subterraneous rivers are also known to exist; and the explosion of gunpowder in a cavern of Derbyshire, England, caused the rushing of a mass of waters through the interior region.

FAVORABLE SIGNS OF THE TIMES.

If there be any one characteristic by which this age is distinguished from another, it is that of excitement; and, generally speaking, an excitement on subjects that are intrinsically good. It cannot be expected indeed, as human nature is, that scarcely any excitement, however good may be its objects, or however proper the means which are applied to produce the emotion, should be free from all impurities, exempt from all excesses, or disencumbered from all human infirmities. When we consider the elements of which human society is formed, its liabilities to be moved to action under the influence of impure motives, to be biassed and led into error by rash and precipitate judgments, and imperfect councils, we need not be surprised at finding many excesses to correct, errors to rectify, and numberless infirmities to bear with. The wonder rather is, that, amid so many clashing interests, strengthened as these are by so much selfishness, pride, and obstinacy, there should be no more exhibitions of corrupt passions mingling themselves with, and disturbing the repose of human society.

The mind of man is ever active. And at a time when there is so little of national animosities to call off and to concentrate the energies of one community toward another, by which the minds of men are left at liberty to act upon each other in opposite directions, to scan one another's motives and objects, there is much less of private bickerings, of tumultuous assemblages, and of rough dealing one with another, than we might reasonably expect.

To what is this owing? Doubtless to a moral and religious influence. For some years past, there has been a gradual movement' upon the face of the waters,' and light, spiritual and intellectual light, at the command of God, has been diffusing itself over the congregated mass of human intellect, so that the dark chaos of human nature has become more and more enlightened, its natural asperities have become softened, and its warlike propensities have been tutored to the principles of peace and good will, so far as to appreciate, in some good degree, the benefits of quietness and harmony among the several members of the human family.

Several causes have operated to produce this effect-all originating primarily from that great first cause of all good, God's great love to mankind, as developed in the Gospel of Jesus Christ. Those who attribute this salutary revolution in the public mind to any one insulated cause, we think greatly err, not knowing the Scriptures, nor the power of God' which has most obviously operated through the medium of a variety of causes, themselves the effects of the primary movement set in motion by the Hand that moves the world, to the production of that excitement which is now acting so beneficially on human society.

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