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phenomenon. M. Godehoue has published curious obfervations
The Abbé Nollet was long of opinion, that the light of the
Thus it is probable, that various caufes contribute to the light and fcintillation of the fea; and that the light, which our Author attributes to agitation and friction, is different from that which is extended far and near, feems to cover the whole furface of the ocean, and produces a moft striking and fingular appearance in the torrid zone, and in the fummer season.
This hypothefis was alfo maintained in a treat fe published at Venice, in 1746, by an Officer in the Auftrian fervice, under the following title, Dell' Eletrecifmo.
Defcriptions des Volcans eteints du Vivarais & du Velay-A Defcription
HIS noble work, which is enriched with twenty-five plates,
T curioufly after drawings on un
der the inspection of the Author, will, no doubt, attract the at-
tention of the Public in a particular manner, as the discoveries of Sir William Hamilton, and other naturalifts before him, relative to volcanos, have produced a confiderable revolution in our ideas, with respect to one important branch of the theory of the earth. If any one had affirmed, twenty years ago, that all the extent of Italy, from Rome to Sicily, derived its fertility from the fubterraneous tillage of volcanos, that these fiery eruptions formed the mountains from whofe fummits they fend forth their Hames, that the greateft part of the cities of Auvergne, Velay, and Vivarais are built upon ancient volcanos, in a compass of more than 80 French leagues, and that the foil of thefe different provinces, where the eye beholds, at prefent, rich harvefts, enamelled meadows, and blooming orchards, is a compound of bodies vitrified, calcined or reduced to afhes, he must have expofed himself to contradiction, and perhaps to ridicule. And had any adventurous theorift gone a ftep farther, and maintained that the furprifing rocks, which rife in the midst of thofe diftricts (whofe bowels were formerly tormented with fubterraneous flames), and which in their colour and hardnefs refemble iron, were, themfelves, originally melted and formed, amidft fulphur and bitumen, in thofe immenfe furnaces, and thrown up from thence in tremendous explofions, -the man would perhaps have been looked upon as delirious.
Nevertheless, by fome late near and bold approaches to the fublime terrors of Etna and Vefuvius, and by a close examination of the various bodies, thrown up by their eruptions, it has been found, upon comparison, that bodies of a like nature have been obferved in many countries, where the existence of no ancient volcano had ever been fo much as imagined. The difcoveries of M. Guetard, who obferved the remains of volcanos at Volvic, Pui de Dome and Mont d'Or in Auvergne, and mentions other mountains in France, which formerly fent forth ftreams of lava, are well known. In the year 1760, M. Defmareft publifhed, in the Memoirs of the Academy of Sciences at Paris, his Obfervations on the Bafaltes of Germany, and, at the fame time, on thofe of Cauffe de Beffan and St. Tibery, in the lower Languedoc. We find alfo in the fecond volume of M. Guetard's Memoires fur differents Parties des Sciences et des Arts, a memoir concerning the Bafaltes of the ancients and moderns. M. Guetard, when he publifhed this memoir (in 1770) ascribed the formation of the prifinatic columns of the Bafaltes to the depofition of ftony matter from an aqueous fluid, but afterward renounced this opinion, when, vifiting, with the Author of the Work now
* See an account of thefe Obfervations in our jad Vol. p. 619.— See alfo Vol. 51ft, December, 1774. p. 458. for an account of the Bafaltic rocks of Staffa, defcribed by Mr. Pennant.
before us, the extinct volcanos of Vivarais, he perceived that the Bafaltic columns had the fame origin with the lava.
Our ingenious Author gives here a compleat and circumstantial account of the extinct volcanos of Vivarais and Velay; and confines himself to thefe, as Meffrs. Guetard, Defmareft, and Montet have undertaken the defcription of the volcanos of Auvergne and the lower Languedoc. The frontispiece of this vo lume exhibits on a double folio-leaf, a view of the principal volcanos, already known, and which continue to emit flames, fuch as Etna, Vefuvius, Hekla, Mount Albours, near Taurus, the ifle of Fuego or St. Philip, the Pike of Teneriffe, the volcanos of Arequipa, Carrapa, Malahallo, &c. Thefe volcanos are reprefented in their natural fituation and forms, after the most accurate drawings and the beft relations, and to a circumftantial defcription of each, the Author has added a chronological table of their most remarkable eruptions. This is a kind of Introduction to our Author's main object, the extinct volcanos of Vivarais and Velay.
M. FAUJAS DE SAINT FOND begins by an enumeration of all the authors, whether ancient or modern, who have made mention of the Bafaltes in maffes or prifms, and he examines their different opinions relative to the nature and origin of that fubftance. He then proceeds to give a chemical analysis of the Bafaltes, and of the different heterogeneous bodies, which either naturally or accidentally are incruftated with it, fuch as the matrixes of granite, fpath, calx, quartz, filex, or flint, zeclite and fchorl or cheorl, whether they be in irregular mafles or in chryftals. The Reader will find here an accurate reprefentation of the Bafaltes in all its different forms, in maffes, in balls, in columns caft, as it were, in one mould, in jointed columns, Jiratum fuper ftratum, together with fpecifications of the differentkinds of lava, folid and porous, of the peperins, the Tufa, the pouzzolanes, and the methods of employing this latter fubitance in cement and buildings.
We meet next in this Work with an accurate map of the Vivarais and Velay, with drawings of the craters or mouths of the extinct volcanoes, and marks to indicate the places where the feveral volcanic bodies are difcernible. This is followed by the Author's journals of the different excurfions he has madem thefe provinces; and these journals are both entertaining and inftructive; they contain defcriptions and reafonings concerning volcanic eruptions, that illustrate several branches of natural hiftory, and may be made ufe of in bringing to farther degrees of perfection the theory of the earth. They are alío accompanied with drawings, which exhibit ftupendous views of Bafaltic columns, which our Author calls Giants Causeways, making a generical name of a denomination that has been hi
therto confined to the Bafaltic maffes and columns in the county of Antrim in the north of Ireland. It now appears that volca noes were the giants that formed thefe ranges of columns, whofe erection is unaccountable on any other principle, and which the facts alleged by our Author, by Sir William Hamilton, the learned Ferber, De Saufure, and other celebrated naturalifts, render abundantly evident.
It is proper to obferve, in concluding this Article, that all the plates, each of which is accompanied with an interefting explication, have been engraven after drawings, made from the objects, by M. A. Ed. Gautier Dagoty, whofe excellent talent for drawing and engraving has been happily animated, on this occafion, by his warm attachment to the ftudy, and zeal for the improvement, of natural hiftory.
Nouveaux Memoires de l Academie Royale des Sciences et Belles-Lettres, annie 1775, Avec Pifcire. -New Memoirs of the Royal Aca. demy of Sciences and Belles-Lettres of Berlin, for the year 1775, with the History relative to that year. Berlin. 4to. 1778. HISTORY OF THE ACADEMY.
HIS Volume exhibits too large a quantity of interesting materials to admit of our paying any attention to the ingenious adulation of the Perpetual Secretary on the anniversaries of the king's birth and acceffion; or to other transactions of the Academy that appear to us of inferior moment.
The first thing worthy of notice we meet with in the Hiftory of the year 1775, is the extract of a letter from M. D'ANSSE DE VILLOISON, member of the Academy of Infcriptions at Paris, and of thofe of Berlin, Gottingen, Manheim, &c. to M. FORMEY, in which he mentions his defign of giving a new edition and a Latin Tranflation of Cornutus his Treatife on the Nature of the Gods, which (in a very maimed and innacurate condition) is inferted in the Opufcula Mythologica of Gale; under the name of Phurnutus. As M. de Villoifon confiders this work as of the utmost importance to mythological fcience, and as containing a catechism and abridgment of the doctrine of the Stoics, he has taken confiderable pains on this edition. From fix MSS. in the French king's library, feven at Florence, and one at Augfburg, he has been enabled to correct above fix hundred paffages of this Author, and to restore a multitude of words, and alfo of whole lines, that are wanting in the prefent editions. He has also added a confiderable number of critical, grammatical, and philofophical notes, in which he either gives an account of the changes he has made, or illuftrates the doctrines of the Stoical philofophy, or explains the allufions to that philofophy, which Cornutus makes fometimes in a fingle word. But this is not
all; for M. D'ANSSE DE VILLOISON proposes, in this letter,
We find by another fragment of a letter from this learned
Report of the Contents of a Memoir of Profeffor MAYER, con-
A Memoir of the Abbé PERNETY, concerning the means of
Concerning magnetic Cures performed at Vienna,-This is the