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crystals of each species, for without such knowledge, it would often be impossible to recognise those forms which are incomplete or irregular in regard to the number and extent of their faces,' &c.

To this plan we object; 1st. That the primitive form cannot be distinguished in more than a dozen cases within the whole compass of mineralogy, without the instruments and skill of a lapidary;2dly, That the primitive form is not always the same in minerals, usually classed under the same order, genus, and species;—3dly, That the study of Hauy's diagrams and wooden crystals to show how a secondary form may possibly arise from additions, accretions, detractions, and compressions, would be a study of itself, enough to absorb exclusively too large a portion of time, even if it were true and well. founded;-but, 4thly, That the growth of crystals, and the forms they assume, are governed

by laws of compression and attraction perfectly different from any assigned by Hauy. M. Methuon has shown this, in a way that goes to the utter destruction of the very ground-work of the Abbe's theory. It would be a much lighter task to learn by rote, all the different chrystalline appearances of a mineral as they actually occur in natural situations, than to depend on diagrams, founded on a theory not only unsupported by sufficient facts, but contradicted by the latest observations.

We object to Professor Cleaveland's method in this respect, that the primitive forms of crystals are not of the greatest, but of the least, practical importance to a mineralogist; not merely for the reasons above assigned, from the scarcity of well chrystallized minerals, and the difficulty of arriving at the primitive crystal; but from the reluctance also which a mineralogist would have to sacrifice a fine specimen for the detection of its nucleus, when a chymical analysis of the dust or fragments would be so much more conclusive and satisfactory. Hence, without rejecting chrystallization, more than any other feature in the physiognomy of a mineral, -well knowing how often it aids in determining the character,—we are not inclined to lay so much stress as our author does, upon the real or supposed primitive chrystal. It cannot, besides, be applied to one specimen in five hundred of actual collections; which, unless collected by some disciple of Hauy or Bournon, with an express view to the science of crystallography, consist at least in that proportion of minerals amorphous or imperfectly crystallized. Neither is this attention to the primitive form of a crystal likely to be paid in practice. We want to discover in a country we are exploring, sypsum, or limestone. We are told, that the primitive form of gypsum is a foursided prism, whose bases are parallelograms with angles of 113 deg. 8 min.

and 66 deg. 52 min., the sides of the base and the height of the prism as the numbers 12, 13, 32. Of limestone we are told, that it is a rhomb with two acute angles, 78 deg. 28 min.; and two obtuse angles, 101 deg. 32 min. The faces of this rhomb are inclined to each other at right angles of 75 degrees 31 minutes, and 104 degrees 42 minutes. Let any practical man apply these measurements to the usual varieties of plaister of paris and limestone; and say whether they can aid him in any manner, to detect the object of his pursuit? Will not a drop of acid and the thumb nail answer the purpose quicker and better? This very ingenious, but too theoretical system of Hauy and his followers, reminds us of the playful objections of Simplicius to the philosophical theories of his day. °A man says he, meets another in a lane; and wishes to inquire whether a friend of his has lately passed that way. Must he say,

Friend, have you met a man lately going down the road?' No; he should address him in the language of philosophy,-- Animal, rational, risible, two legged, and without feathers, five feet eight inches high, have you lately met, during your peripatetic excursion, another animal, rational, risible, two-legged, and without feathers, six feet high? For practical purposes, a small vial of acid, and a blowpipe, are of far more value than a goniometer, especially in this country; where, we want travelling, exploring mineralogists, rather than closet collectors of rare specimens, and profound crystallognosts. Professor Cleaveland, however, has only followed the authors he has consulted; and, right or wrong, he has the greater number of mineralogists on his side; for the French philosophers, in mineralogy, as in chymistry, have their own school, and their own propagandists. Our objections are more to the system adopted, than to the professor for adopting it. It would lead us too far to make remarks upon

the different minerals the author has described; but a few observations have struck us, here and there, which it may be well to notice in case of future editions.

P. 127. The sulphat of strontian, said to be found near Frankstown, has never been authenticated as to its locality. Dr. Muhlenburg was told, it came from there: the locality we suspect is made on his authority; but it has not been confirmed

P. 129. Mr. Farrady and Sir H. Davy, have lately given an account of native lime sent to them from the south of Santa Gonda, near the road to Pisa. Lime 82,42. Silex 10,57. Iron 2,82. Alumina 1,34. Loss 2,86. Ann. of Philos.

P. 172. Magnesian limestone, is said on the authority of Smiths on Tenant, to be injurious to vegetation when calcined. Later experiments in England, and in Pennsylvania, have

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shown, that its injurious properties were rather to be ascribed to the quantity used, than to the quality of the lime. It cannot be used so freely as the common lime. Almost all primitive lime stones, keeping company with magnesian rocks, contain magnesia.

The article, Basalt, p 278, is drawn up with great care; but it seems to us strange to say, that this mineral is never crys. tallized! Is not all calumnar basalt crystallized? Is there more anomaly in the sides of a crystallized column of basalt, than in a crystal of carbonat of lime? What definition of crystallization will exclude either the prismatic column, or its articulations? Basalt is said to be usually incumbent on other rocks, as granite, gneiss, mica, slate, &c. We apprehend that it seldom covers immediately primitive formations; and if the floetz trap should be basaltic, as the French and Italian mineralogists contend with great appearance of reason, it is often the exterior covering of very recent formations. The author before us says, that basalt probably never rests upon lava. The question is not settled whether basalt be not a lava.

P. 286. Basalt sometimes contains organic remains, both of animals and vegetables.' This assertion will be true or untrue, according to the substance called basalt. In the argument where it is placed, it amounts to a petitio principii; for it is not yet settled that the secondary trap of the Wernerians is not a basalt. "The analysis of basalt shows it contains water, which lavas do not. Now as lavas, like basalt, contain pyroxene, idocrase, leucite, titanite, zeolyte, &c. they certainly contain water with respect to these crystallized substances. We do not, at present, recollect the comparative analysis of basalt and lava, on which this assertion is founded; for to prove it, the experiments should be purposely made. Many other remarks occur on this interesting view taken by Professor Cleaveland, of the probable origin of basalt, whether neptunian or plutonian. He inclines to the former; or rather, adopts the neptunian origin of this substance. But he does not mention two facts that appear to us decidedly to overthrow the neptunian theory: 1. That whenever basalt cuts through a coal formation, or forms a dyke in it, the coal immediately contiguous, is actually burnt-decomposed by fire. 2. Cordier has lately shown, that when coarsely powdered, the fragments of basalt are precisely similar to those of lava; that in short, the one cannot be distinguished from the other; the same substances being found in both.

P. 330. Amianthoide. The termination oid is so very indistinct, that its use is greatly objectionable. What is amianthoide? Something like unto amianth. We suspect this to be the sub

stance found in the gneiss at the end of the Schuylkill canal near Philadelphia.

P. 333. Coccolite. The substance so called from Lake Champlain, is so very different from the common coccolite of Europe, that it must be analyzed before it can be classed. It is not sufficient that it is in granular concretions;—there must be some chymical relationship. The coccolite of Lake Champlain is much more like garnet; judging from its appearance merely. The term coccolite is not characteristic; as a vast variety of minerals are found in granular concretions.

P. 349. A stone extremely similar to the verd antique, has been found near Haddam, in Connecticut; and is an excellent substitute for this beautiful marble. Indeed, many substitutes might be found by exploring serpentine regions. Perhaps the serpentine marble of Milford Hills, mentioned by Professor Cleaveland, may be the same with the slabs brought to Philadelphia.

P. 359. 'Argillaceous minerals. These substances never exhibit crystals, nor even possess a crystalline structure. The hardest and most perfect crystals that are to be found-the diamond excepted, -such as the sapphire, the spinelle, the adamantine spar, the diaspore, &c. are composed chiefly of argillaceous earth.

P. 368. Kaolin: this mineral abounds in the neighbourhood of Philadelphia; fit for all the purposes of the manufacturer of porcelain. So does fine clay, whether for the finer kinds of pottery, or the glass-work crucibles, in various places along the river Delaware, from Burlington to Newcastle.

P. 407. It were to be wished the Professor had not only borrowed from Jameson, the indications of coal strata, but distinguished as Jameson ought to have done, between the smokeless anthracite, and the bituminous coal, which are found in very different geological situations. The former is usually an inhabitant of transition,--the latter of floetz or secondary regions. In Pennsylvania, the coal to the east of the north east branch of the Susquehanna, is in transition country, and is anthracite: the bituminous coal is on the west and to the west of the west branch of Susquehanna; and thence indefinitely down the Ohio and on its stream, in the great Mississippi basin.

P. 411. Coal has been used with success in baking stoneware, but neither coal nor coke has hitherto been employed in baking porcelain.-Brongniart. This is a mistake; it is commonly so employed in England.

Pp. 504, 505. Earthy phosphat of iron: green iron earth. The blue and green iron earth of the Jerseys, does not appear to be a phosphat of iron; for on being dissolved in nitric acid, neither nitrat or acetat of lead, produce a phosphat of lead. These earths appear to be hydrats of iron merely. The crystallized green iron earth of that state, is a beautiful mineral.

P. 508. Chromated iron. Add, about a mile from the Fox Chace, on the old Chester road, fourteen miles from Philadel. phia, and on the tract called Soldier's Delight, at the back of Roysterstown, about fourteen miles from Baltimore.

These remarks on the minerals described, might be greatly extended; but more on the subject would be out of place here; and we proceed, therefore, to the last part of Professor Cleaveland's work,-his introduction to the study of geology.

In this part, he presents the reader, in a plain and summary, but clear and condensed manner, with the general facts ascertained by geologists. He gives us, first, his own arrangement of rocks into primitive and secondary; and, then, Werner's arrangement into primitive, transition, and floetz, or secondary. He furnishes us, also, with a brief view of the Wernerian, or Neptunian, and of the Huttonian, or Plutonian, theory of the causes that have produced the actual arrangement and phenomena;--the general facts relating to the history of veins;—the Wernerian arrangement of rocks; and a description of them according to that arrangement. All this is neatly and concisely done. The great objection to it, is, that it is too concise; though if considered as a mere appendix to a treatise on mineralogy, it is perhaps long enough. What is done in this respect by Professor Cleaveland, is done well; and it may not be impossible that this circumstance induces us to wish it were more extended. In some parts, indeed, we do not altogether coincide with him; but we have no pretensions to assert, that the mistake is on his side. In the arrangement of rocks, for instance, the Professor, with the French geologists, seems to reject the transition class; though the psammites of the French geognosts are really transition rocks. Werner, who has applied his very accurate observations on the Hartz mountains to the globe of the earth, has perhaps unnecessarily burthened the valuable information he has presented to us, with names that imply a theory such as transition. But the distinction he means to insist on by this name, certainly exists in nature.

Are there not two great classes of rocks,-one, whose leading character is, that the rocks comprised in it, are distinctly inclined--another, whose character is, that they are comparatively, level and horizontal; floated, floetz? These are facts, involving no theory. The primitive and transition of Werner, will be included in the first class—the secondary in the other. But it is undeniable, that among the inclined rocks, the more recent are manifestly formed of the debris of those that preceded. These are Werner's transition rocks. As to the two

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