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if a fact is owing to a certain cause, it is necessary to know the

to be classed in a certain order, to aid the memory in recollecting them. Notwiihstanding this long and useless list, we every day see some new systems advanced, and our journals filled with defences of their authors. How can men of talents be so discordant, and continue such controversies? The reason is, that if any one of them were right, neither be nor the others could ascertain it. To discover

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nature of the cause, and the circumstances of the fact. What, there· fore, are the authors of geological systems, but persons who seek the causes of facts before the facts theniselves are known? Can we conceive an end more chinerical? Yet we are ignorant, not merely of the interior of the globe, but even of its most exterior crust. Hence, some persons will have millions of years for the formation of secondary mountains, while others pretend that about 5000 years ago they were formed in one."

It appears that there are still above six hundred species of unknown shells in the basin of Paris, and the bones of tivelve or fifteen' unknown quadrupeds, notwithstanding the smallness of its extent, and its convenience for study. La Marck has been able to ascertain the species of forty or fifty of the shells, but even these have been the labour of

many years. Yet ten or twelve theories of the formation of this basin have been published, not one of the authors of which knew its contents. The following positions are laid down by the authors, as the proper method of commencing and pursuing the study of geology, divested of visionary speculations, and founded on facts only. These points should be ascertained, and clearly established, before attempting to solve the grand question of “ the causes which have reduced our globe to its actual state.”

Ist. To search if the division of great chains in one middle and two laternal banks or dikes, observed by Pallas, and developed by Deluc, is invariable, and examine, as Ramond has done on the Pyrenees, the causes which sometimes conceal them.

“ 2d. To examine if there is also any thing certain or uniform in the succession of secondary strata, if such a kind of stone is always below such another, and vice versa.

" 3d. To proceed in a similar manner with the fossils, determine the species which appear first, and those which are only seen afterwards ; discover if these two sorts never accompany each other, if there are any alterations in their appearance, that is, if the first found appear a second time, and if the second have then disappeared.

“ 4th. To compare the fossil with the living species more minutely than has hitherto been done, and determine if there is any

relation between the antiquity of the beds, and the similarity or dissimilarity of fossils with the living beings.

“ 5th. To determine if there is any uniform relation or cor

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respondence of climate between fossils and those living beings, which most resemble them; as for example, if they have migrated from the north to the south, the east to the west, or if there have been mixtures and jrradiatiulis.

6th. To determine what fossils have lived where they are now found, what others have been transported there, and if there are, in this respect, uniform rules with regard to the strata, species, or climate.

“ 7ih. To follow, minutely, their different strata throughout their whole extent, whatever may be their doublings, inclinations, ruptures, and slopings; and, also, to determine what countries belong to one and the same formation, and what others have been formed separately:

ro 8th. To follow the horizontal beds, and those which are inclined in one or different ways, to determine if there is any relation between the greater or less constancy in their horizontal position, antiquity, or nature.

gth. To determine the valleys in which the re-entering and saliant angles correspond, and those in which they do not; also those in which the strata are the same on both sides, and those in which they differ, in order to discover if there is any relation between these two circumstances, and if each of them taken apart has any analogy with the nature and antiquity of the strata composing he heights which limit the valleys.

“ All these points are necessary to its elucidation, if we wish. to make geology a body of doctrine or a real science, independent of every desire which we may have to find an explanation of facts. We dare affirm, that there is not one of those points on which any thing, ab-olutely certain, is yet known, everything which has hitherto been advanced, being more or less vague. The greatest part of those, who have trèaled of such subjects, have considered them rather as They answered their system, than according to impartial observations. The fossils alone, singly considered, would furnish matter for the study of 30 years to several industrious philosophers; and their connections with their strata will still require

many more years of travel, of boring and other arduous researches.

M. André, in imitation of Saussure, traversed the Alps, from St. Gothard to St. Bernard, passed the Jura, and examined the Vosges. He describes Mont Blanc, the Vallais, St. Gothard, Jura, and Vosges, with great precision and perspicuity. To his descriptions he has added several others from the best authorities, so that his work is very complete. The following is an abstract of his theory, which his reporters, M. Haüy, Lelievre, and Cuvier, have in part adopted as their

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“ He thinks that the actual arrangement of the surface of the

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carth has not existed from a very remote epoch, and he endeavours
to prove it, like Deluc and Dolomier, by the progress of despositions
(éboulemens,) and by, that of decomposition and formation of soil
(atérrissemens.) He likewise thinks that this arrangement is
totally owing to a cause unique, general, uniforni, violent, and
prompt; and appears to attribute to this cause even the tra sport of
fossils. He attempts to prove that neither volcanoes, earth quakes,
rivers, nor currents, could possibly arrange the surface of the earth,
as it is in the present day. These ideas have also been entertained
by several celebrated naturalists, especially when restricted to the
last change experienced by the earth.

On the above opinion we shall only remark, that M. André's

unique, general, uniform, violent, and prompt cause," explains nothing, and is not a tittle more intelligible, than to say that the Deity made the world, as we now see it. Observing, too, that the whole globe is composed of strata, often broken and irregular indeed, but still perceptible, we do not see the necessity or propriety of imputing its present appearance to" an unique and prompt cause." The strata of fossils would indicate succession, while other appearances are in favour of a prompt, but perhaps not a general cause.

(To be continued.)

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Précis analytique des Travaux, &c.
An analytical Summary of the Transaction of the Society of Sciences,

Literature, and Arts, of Nancy, during the year 1806, 12mg,
Nancy.

As we have given some extracts in the appendixes to vols. 30 and 31, from the transactions of the society of Nismes, we are happy in being able to contrast them with those of Nancy, where the genius of Germany has rather the ascendancy over that of France. This little volume, indeed, cortains abstracts of several very ingenius papers, which are more directed to chemical researches, than those of the southern societies.

M. Gueneau d'Aumont applies the rule given by Laplace, to reduce a whole number into a fraction, or into any other denomination, whether fractional or decimal. He enters at length into the theory of fractions, shews that all scales of numeration present fractions analogous to decimal fractions, and

proposes to call them natural fractions. In a "Dissertation on the Law of Continuity erectedinto a principle by Leibnitz,” M. Haldat expresses his doubts respecting its accuracy and conformity with the phenomena of nature. To the arguments drawn from the principle of sufficient reason, on which

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Madame du Chatelet endeavoured to support this law, he opposes all the experimental proofs, founded on the opposition of the most active powers in nature. He relates a great variety of facts, where the repulsive powers evidently predominate ; examines Bonnet's proofs in favour of the law of continuity; and, in referring to curious experiments, the results of which tended to shew the destruction of certain species, he endeayours to prove that the famous chain, with which Leibnitz wished to bind all beings, is purely imaginary; and that nature, in many cases, where the simplicity and fecundity of her means require a different mode, deviates from her progressive course, in order to obtain her end sooner, by making the most.opposite means concur in maintaining her marvelous harmony. We do not, however, think that the author has either exhausted the subject, or established his point incontestably; but it is a subject so unproductive of any practical utility, and so little likely ever to be perfectly determined, that it may by some be considered a waste of time and ingenuity to enter into the enquiry.

The composition and use of James's powder, called by the French English potvder, have exercised the Pharmacologists in France not less than those in England. Doctor Valentin, who highly recommends these powders, in a laboured dissertation, states them to be composed of 12 parts of tartrite of potash and antimony, and 120 oftartarized diaphoreticantimony, and ground and mixed together, which form a powder, of which from 2 to 14 grains are a dose, taken two or three times in the day. It was, however, ascertained by M. Mandel, that the antimony in a state of oxyd is the basis of this composition, which is yet unknown to all the foreign chemists. The following substitute is proposed for it ; oxyd of antimony by nitre 24 grains, tartrite of potash and antimony 4 grains, powdered and divided into 6 doses. Doctor Valentin has also collected a number of instances, to prove that the yellow fever of America, is not contagious. It would, no doubt, be very useful, if people were convinced that this fever is not contagious, but at the same time, keep at an equal distance from it, as if it were. By acting in this manner, such aumbers would not die of fever, as they now do ; neither would others be deluded into a fatal security, by depending on the . useless quack-remedies which are advertised for the prevention and cure of this destructive fever.

A curious “ memoir on fossil bones of an extraordinar size, found in a hidden cave at St. Martins, near Cominercy,"

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was furnished to the society by M. Braconnot. These horns are supposed to have belonged to a large species of ox, common in the days of Cæsar, but very rare at present, and called by the German Aurouchs, the bos urus of modern naturalists. The chemical analysis of these horns afforded a considerable portion of gelatine and bituminous matter, not hitherto known in any ancient fossil bones. M. Braconnot succeeded in disengaging the gelatine from the phosphat of lime by nitric acid. In 100 parts of the fossil horns, found at St. Martins, there are 4.0 ferruginus quartzose sand ; 4.6 solid gelatine; 4.4 bituminous matter : 0.5 oxyd of iron : 0.7 alumine: 1.0 phosphat of magnesia ; 11.0 water ; 4.5 carbonat of lime, and 69.3 phosphat of lime: the two latter were composed of phosphoric acid 2.83, and lime 41,0.

Could we give implicit faith to M. Mandel's comparative analysis of soda, from Alicante, and that from Dieuze, we should conclude that the latter is doubly stronger than the former, and that the proportion is as 5 to 12. Had this proportion been given as 5 to 7, we might have believed the author's experiments to be accurate, but knowing the strength of Alicante soda, we must hesitate to adopt such a disparity. We suspect that the relative strength of the alkalis, will never be correctly ascertained, till Mr. Þavy's discoveries are applied to this purpose. The same author has discovered a spurious kindof pepper in France, called by merchants small pepper (petit poivre.) The means which he adopts for discovering and separating this spurious species from the genuine kind, are making them into a paste and macerating them, when the real pepper resists the action of the water.

The scarcity of fuel in various parts of France, has occasioned considerable alarm, and various projects for increasing it have been proposed. M. Plonguer recommends the reduction of a tract of land, in the department of Meurthe, into a peat-moss, from which all the inhabitants of the department might be supplied with fuel. The prejudices of the people in favour of wood-fuel, would not be easily reconciled with that of peat; but dire necessity, the consequence of revolutionary frenzy, would enforce its use.

M. Haldat has made some very ingenious "Researches on double vision," the results of which he has laid before the Society of Nancy. He inquired if this combination of sensations takes place in all cases where the perception of objects is effected by means of instruments; if it existed where the sensations were homogenous or heterogeneous, produced by similar or dissimilar impressions. His experiments were

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