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REVIEW.

Nec vero hæ sine sorte datæ, sine judice, sedes.-Virg.

ARTICLE 4.

Geological and Mineralogical Papers.

In the following review we shall notice several papers on the

geology and mineralogy of our country, which have appeared in the transactions of different societies. We had hoped to preface these notices with some general account of the state of those sciences in our country, but we have not been able to collect the requisite information to make such an account complete. These studies have attracted considerable attention among us. Our country has been explored by different mineralogists, particularly by Mr. Maclure. According to him, its geology is peculiarly simple; and there is not that confusion and intermixture of different rocks, which is to be observed in almost every part of Europe.* He has given it as his opinion, that in a few years, the geology of the New continent will be better understood than that of the old.† Lectures on the sciences of which we are speaking are regularly delivered in Boston and Philadelphia, and at Columbia, Yale, Harvard,

*La variété confuse et fatigante des diverses roches dans presque tout les parties de l'Europe, ou j'ai occasion de les examiner, lasse la patience, et met en defaut toutes conjectures; au lieu que sur ce continent-ci, on peut raisonner a priori, et conclure, sans grand risque de tromper, qu' en tel et tel lieu, telles et telles roches se trouverant. [Letter to J. C. Delamétherie, upon the geology of the United States, published in the Journal de Physique, vol. 69, p. 201.]

† Je suis cependant porté à croire dans ce moment, que sous peu d' années nous aurous une connoisance plus complete de la géologie de ce continent, que vous n'en avez de celle du continent de l'Europe. See Letter, &c. as above, p. 203.

and Bowdoin colleges, and probably at some others. Cabinets of minerals of considerable value have been collected in different places. That of Harvard University contains a number of rare and valuable specimens, the gifts of Dr. Lettsom of London, and of the National Convention of France. A valuable cabinet is likewise the property of Yale college, and colonel Gibbs has lately deposited in that seminary a very rich collection, the original cost of which, to the European proprietor, is said to have been four thousand pounds sterling. There is also a cabinet at Bowdoin college, which has many specimens of our native minerals, and which has lately been enriched by a collection made in France, and arranged partly under the inspection of the Abbé Haüy, formerly the property of the late Mr. Bowdoin of Boston. Numerous other cabipets of various value, both public and private, are to be found in different parts of the country. A valuable Mineralogical Journal has been commenced by Dr. Bruce of New York, and we hope will be continued. From this, and from the Medical Repository, and perhaps from some other works, as well as from the papers which we are about to notice, various information may be collected respecting the geology and mineralogy of our country. 、、

MEMOIRS OF THE AMERICAN ACADEMY.

No. XXIII. Mineralogical observations made in the environs of Boston, &c. By S. Godon.

SEVERAL Considerations render this an interesting paper. The observations indeed embrace but a small extent of territory, the environs of Boston. But M. Godon very pertinently remarks in the introduction, that "these local observations become even worthy of general attention, when we consider that from the insulated descriptions of several parts of the earth, we may expect in time an universal mineralogical map, which will afford in some measure, under a single point of view, a representation of all the (mineral) riches in the world." By limiting the extensive views, expressed in the foregoing

remark, we shall probably be able to form a more correct estimate of the value of communications, similar to the one under consideration. We may then say, that a few such local observations combined will enable us to prepare a mineralogical map of Massachusetts; a few more will give us a similar view of New England; and thus, without being discouraged by the magnitude of the undertaking, we shall almost insensibly attain to a mineralogical map of the United States. This paper has also a local interest, from being the first publication of mineralogical observations in this state; and with the author we are inclined to anticipate, that these observations will be extended by the citizens of Massachusetts, "whose increasing taste for mineralogy presages a flourishing period for this science."

For the present state of mineralogical knowledge in this vicinity, we believe the public are under no inconsiderable obligations to M. Godon. He has excited a spirit of mineralogical research by his public lectures, and by communicating somewhat of his own ardor and accuracy of observation.

In the true spirit of a practical minéralogist, whose chief object, in the present state of the science, is to accumulate facts, M. Godon expresses his fears of leaning to any geological system so far, as to permit his observations to be thereby influenced. If at any time he ventures to offer a hypothetical remark, it is expressed with great modesty and diffidence, We wish these good feelings had been able to shield him from a very dangerous attack of that epidemic among system makers; a disposition to invent new names. M. Godon appears to be impressed with the idea, that the peculiar aspect of certain rocks in this country renders a change of nomenclature necessary. We differ from him in believing the proposed changes both unnecessary and perplexing to the student. But, granting the existence of numerous imperfections in the present nomenclature of rocks, we are by no means ready to admit the propriety of introducing changes in the present state of the science, unless absolutely necessary. Observations are daily accumulating; and our knowledge, or rather opinions, must

vary with increasing facts. If this liberty of unceasing change in names be tolerated, our list of synonyma, already too long, will become insupportable. When new substances are discovered, it is certainly necessary to make additions to the nomenclature; but when the progress of discovery meets only new varieties of substances, already known, which may render the received name imperfect, we think the interest of the science requires, that these new varieties should stand under the received name, and that description rather than the fabrication of new words should be the present remedy.

The changes, which M. Godon has proposed, appear to us unnecessary, because no new species or sort of rock is described. It must here be remarked, that the word species cannot be applied to aggregated minerals in so rigorous a sense as to simple minerals. It is true M. Godon may have observed in some particular species of rock well known, an accidental ingredient or variety of aggregation, somewhat uncommon in that kind of rock. But surely the accidental occurrence of any simple mineral in an aggregate cannot entitle that aggregate to a new name. If every imperfection or casual variety observed in aggregate minerals is to claim and receive a new name, the nomenclature will become endless. Those, who have made some progress in the science, will become discouraged; and the pupil will turn back at the threshhold. But we must proceed to a brief analysis of the paper.

After a short introduction, the writer gives us 'Definitions and preliminary explanations;' in which some of the proposed changes of nomenclature are mentioned. Then follow notices of alluvial deposits and waters. With the exception of a few alluvial deposits of sand and clay, the environs of Boston, and indeed the greater part of Massachusetts, are entirely primitive. "The country is not mountainous, but its surface is largely and often deeply undulated. The springs, which arise from the most elevated part of the ground, often unite in basons, sometimes surrounded by hills, and form a multitude of ponds, which contribute to the embellishment of the landscape." Most of the waters, which issue in springs at the surface of

the ground, are impregnated with some foreign principle; as carbonic acid, the carbonates of lime and iron, sulphate of magnesia, &c. To the proportion of clay, existing in the alluvial soil, on which Boston is built, the inhabitants of that town are indebted for the goodness of their waters. This elay prevents the infiltration of sea-water.

The variety of minerals in the vicinity of Boston, though not numerous, is interesting. The first mineral described is the amphiboloid. We are now to say

Amphiboloid of Godon.

Roche Amphibolique of Haüy.
Grunstein, Graustein of Werner.

Are we uncharitable in believing that the above list of synonyma of Godon, and Haüy, and Werner discloses one powerful motive, which influenced M. Godon to introduce his changes in nomenclature? Amphiboloid is thus defined: "an aggregation, most frequently of amphibole and felspar, admitting in its composition quartz, epidote, talc, mica, and almost always sulphurated iron. Amphibole (hornblende) which characterizes this rock, is supposed to be the predominant substance.". Now this is precisely the same rock, which others have describ-, ed under the names of amphibolic rock and greenstone. They also say, that it occasionally admits in its composition foreign substances, as above mentioned. Whence then the necessity of a new name? Amphiboloid is distributed by M. Godon into no less than eight or nine different species; and all these specific distinctions are founded on the variable size or peculiar arrangement of the ingredients, or on the accidental intrusion of some foreign body.

The first species is the common amphiboloid.

The second is the granitic amphiboloid. This has received its specific name from being " perfectly analogous to the black granite of the Italians." The two elements present irregular black and white spots; and the stone is susceptible of a good polish.

The third species is the trappine amphiboloid; because it resembles the trap of the Swedes. The felspar and amphi

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