« НазадПродовжити »
evidently been very carefully read and studied. It is somewhat strange that it did not occur to the lecturer on geology at the New York Atheneum, that his readers might have met with some of these publications ; that he did not catch the idea" (as he tells us Whiston did that of Halley) is evident from the modest manner in which he informs us that
geology is generally considered as embracing a knowledge of rocks merely," and that there is no work published,“ that even hints at the many important points properly treated of under the head of geology.” Had Professor Jameson’s “ Manual” the "Classification of Rocks," by Dr Macculloch, and Messrs Conybeare and Phillips” “Outlines” not appeared, we are somewhat suspicious that the present publication would never have come to light. The fact is, we are sorry to say it, that nine-tenths of these lectures are copied almost verbatim from these works--all that part in particular which relates to highland and lowland, mountain chains, mountains, the bottom of the sea, &c. is from Jameson. The notices of Guettard, on page 27, and of Lehman, on page 28, are from page 42 of Conybeare and Phillips? “ Outlines of the Geology of England and Wales.” The learned authors of that work in their introductory sketch of the progress of geological science have the following very appropriate figure, “ As we approach the middle of the 18th century, we find the scattered rays of information, which alone can be discerned previously, converging into a more condensed and steady light; the disjoined atoms falling, as it were, into a regular system.” How much more beautiful the language of the lecturer to the Atheneum, on page 34. “The few rays of light were scattered, until an unexpected nucleus attracted the wandering atoms and drew them together.” The notice of Saussure, on page 37, is from the 45th of the same work.
In the first lecture we have outlines of the various fanciful and exploded theories of the earth, commencing with that of Burnet. These are very nearly in the language of Professor Brande. The same may be said of our author's account of the theories of Leibnitz, Woodward, Buffon, and others, all of which may be found in Brande's Lectures or in Cuvier's Essay. The theory of Dr Hutton, we are told, is in unison with many geological facts as seen in Scotland. Unfortunately, it is well known to all who have made themselves acquainted with the writings of both Scotch and English geologists, since the publication of the Huttonian theory, that nearly all
wered as embracing ahli
ser in which he indossana wa that rect pris ro work published, "huru bizt 22 points properly treated at der the teada. Hau Professor Jaluron's "M" the - Cascajon of Rocks," by Dr Mucullo , and Main Copriezne aed Phillips” “Oullinen " not appareil, weils someria se cises that the present publication would arian have come u ishr. The fact is, we are sorry to any it, thout nine-tents of tolerares are copied almost vidim these work—a ta ac in particular which relates to high land an: Jovianu, suomiain clair, mountaina, llor balloon of the sea, tí, to ursunThe notices of Govellud, on pare ?", ardo Lesan 22, ar from a 42 of Ciny beare an] Proin tinta if the Colorý oilada
The Spirt of ! work in their insowe
**?". "A: Watch! Whibile
der 162 and drew
-5, Laze 37, is from
Se tem esering with that of
je su otábor's account of 2. V B.200, and others, all
2 3 we's Lectures or in Cuvier's puittiin we are told, is in unison es et II. Scotland. Unfortunate
made themselves acquaintCsod English geologists, 1. teory, thularly all
the gcological appearances relied upon by the learned author of the theory, and its eloquent advocate, the late Professor Playfair, can be explained quite as satisfactorily by other hypotheses. The granite veins of Arran, the porphyry of the same island, the slate at Tarbet and Luss, the quartz rock of Tyndrum, the magnificent granite veins of Garviemore, and innumerable other geological phenomena, have been exawined and described again and again, and made to accord with the previously adopted theory of each observer.
We were somewhat surprised at the bold assertion that Dr Hutton's book continues to be the text book of the best English geologists! There is something indeed approaching to the Futtonian hypothesis in some of their works, but had Dr Van Rensselaer studied these with attention, he would have found innumerable points of difference. Almost the only writer, who may be considered as taking Dr Hutton's work as a text book,” is Prof. Brande, and although Dr Van Rensselaer has apparently made this same work his own text book, he should have known, that however deservedly eminent as a chemist Prof. Brande may be, he has no pretensions to a high rank as a geologist.
in the second lecture our author proceeds to point out the advantages to be derived from the study of geology, in which he shows himself familiar with some of the papers of Mr Maclure, and has given nothing new. He follows
up tem of Mr Brande, and like him tells us, that we do not select the most permanent materials for architectural purposes. This affords a good opportunity of letting us know he has been abroad, and seen the chapel of Henry VII. undergoing repairs.
The third lecture commences with an account of the changes produced on the earth's surface by the formation of peat &c. Although we are fully aware how very compressible this substance is, we should hardly have conceived that the thirtyfive pages of Dr Macculloch’s Essay upon it in the second volume of the Edinburgh Philosophical Journal could have been condensed into about four ; but by some unfortunate accident all that peculiar essence on which the value of the original depended escaped during the process, and we have nothing left but the dry stalks. Thus we have a string of eighty or more hard names, being the list given by Dr Macculloch of the plants from which the different kinds of peat are derived, while the important details and facts are omitied;
the recital of this list must have been listened to with deep interest. Before leaving this chapter, we must not omit the recipe at the close of it for making a volcano; which we presume was furnished by the worthy proprietor of Vauxhall garuen.
If any of you wish for a volcano on a small scale in your garden, take twenty-five pounds of powered sulphur, and as much iron filings, mix them into a paste with water, and place the whole in a large iron pot, covered with a cloth, some little distance under ground. In a few hours, from nine to twelve, the earth swells, heats, and cracks-hot sulphureous vapours arise, and the cracks enlarging, a brilliant flame bursts up, thus forming a volcano in miniature,” &c.
The “ opportunities for the study of geological phenomena in Europe &c.” enjoyed by our author have unquestionably been “ numerous and extensive;" he has therefore an undoubted “ right to form his own opinions," as he remarks in his preface. That “these have generally coincided with the ideas of others” we have the most abundant proof, as will be evident from a few quotations. The following is his “opinion” of what have been termed irregular masses of rocks.
Irregular Masses may be of any size; and often constitute mountains, as is the case with granite, serpentine, porphyry, and the overlying rocks, as trap, &c.
Dr Macculloch in page 99 of his “ Classification of Rocks" says,
Irregular Masses. These may be of any size, eren of mountainous bulk. Examples of them are afforded by granite, and by the overlying rocks, as the traps and porphyries.
At page 129 we have Dr Rensselaer's “opinion” in regard to nodules.
Nodules or imbedded irregular masses is a term lately adopted to include rocks which are not stratafied nor disposed in pseudo-strata (beds) and which do not resemble in their connections other large irregular
The forms of the nodules are various, and they are usually imbedded in the stratafied rocks; but occasionally in granite. The size varies from a foot to a mile. What says
Dr Macculloch? Nodules. Or imbedded irregular masses. This term is adopted for want of one more appropriate, to include rocks which are not stratified, nor disposed in pseudo-strata (beds) and which do not resemble in their connexions the large irregular masses. The form of nodules is very various. Nodules are frequently imbedded in stratified rocks, but they are also found in.granite. The size of these masses varies from a foot to a mile or more.
The fourth lecture we should be half inclined to say was copi