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eauses may tend to influence the equi- circamstances. The facts cited by the librium, the figure or motion, of the author, the details into which he enters earth; these physical conditions, which relative to the operations of casting, had not been hitherto introdaced into and also to the means of augmenting any theories of the globe, will throw solidity and producing aniformity therelight on different questions of geology in, are well wo.thy tbe notice and study and general physics.
of artists. The “ Analytical Formulæ” of M. De M. Dupin recited a report on the la Place, have led to the following re- construction of carriages, and on the sults. The couches or lays, at the causes that render them most liable to greatest depths, are the most dense. be overturned. One of these, perhaps These couches are regularly disposed the principal, is noglecting the execuabout the centre of gravity of the globe, tion of the ordnances as to the loading and they differ but little, in point of of carriages. The conditions, or cases
form, from that of a curved surface, of stability of a carriage in motion, aci formed by the revolution of an cllipsis. cording to the nature, the inclination,
The density of the water is nearly five and the greater or less perfection of the times less than the mean density of the roads, are considered; but the reporter, earth. The heaviest rocks have not without pointing out new forms or methe mean density of the globe at large, thods, lays down data to discover and and of course the interior couches are ascertain them. He refers to the propot of the same nature as the surface. gress which it is natural to expect, from
The presence and distribution of the the growing improvement of the mewaters on the surface of the earth pro- chanical arts, applied to the construcduce no considerable change in the tion of carriages. These are capable of law of the diminution of the degrees, being made lighter, without impairing and in that of gravity or weight. Every their solidity, and better able to en. geological system, founded on the by- counter hazards, without diminishing pothesis of any considerable displacing their firmness. Improvements; also, of the poles, at the surface of the earth, must be planned, as to the form, strucmust be inconsistent with the mecha- ture, and keeping up, of roads; and nical causes now ascertaiped to deter- regulations must be rendered more mine the figure of the earth. The efficacions to produce their effect. temperature of the globe bas not, sen- The author recommends to the gosibly, diminished, since the time of vernment to propose a prize of twenty Hipparchus, (more than two thousand thousand francs, to be granted on the years,) and the effect of this decrease of first of January 1825, to the constructor beat has made no variation in the whole or coach-maker, that, without neglectof this time, in the duration of a day, ing such qualities as are requisite in a the two-hundredth part of a centesimal public carriage, capacity, convenience, second.
and lightness, should secure, also the M. Girard has employed bimself in greatest stability for the conveyance of investigating certain questions relative a given number of passengers, with a to cast iron, and the use of that mate, determinate weight of baggaye. It rial in machinery; also as to the con- will require the experience of a year or ducting of waters, and to the coppers of two, to prove the goodness of such steam-engines. Thé casting of iron carriages. The plans of the carriages
may be readily adapted to the form should be accompanied with a descrip' which nature impresses on bodies, to tive memoir, detailing the calculations
render them capable of a determinate as to stability. In a program should be resistance, with the least possible accurately specified certain facts to quantity of resisting watter. And thus serve as bases to the attempts of prothe figure of hollow pipes may be given jecting mechanists, including fixed to different mobile pieces of a machine, principles, from which the proportion of while casting, like to the stalks of cer- carriages may be derived, as also the tain plants, or to the plumage of birds, best disposition of the loading, so as to M. Girard, who is also author of an acquire the greatest possible stability. excellent “Treatise on the Resistance T'he same reporter, as the organ or of Solids," deduces from bis “ Formulæ" representative of the commission dethe relation between the interior and pnted to examine the work of M. exterior diameters of a hollow cylinder, Marestier, on steam-packets, and the so as to render the cylinder both lighter military marine of the United States of and more capable of resistauce, in given America, detailed the contents of their
analysis. In this, the structure and the globe upon a condactor; a phenome dimensions of steam-packets are iuves- which be was the first to observe. tigated, as also the mathematical results In the limited state of buman knowdeduced by the author, and his descrip- ledge, it is not possible to ascertain the tion of those of America. On the whole, distribution of the electric cofrenis of the committee recommend to govern- our globe, nor even to decide the queso ment to assist or contribute to the tion of their actual existence. If it be printing of the Memoir, as it has to the admitted, we must suppose one part of publication of several other works. these currents to come very near the
Some experiments made in Sweden, surface, as the direction of the magnetic by M. Lagerhielm, communicated to needle is affected by the variations of the academy by M. Olivier, ancient the temperature from day to night. pupil of the Polytechnic School, re. These variations, however, being scarcely siding in Sweden, bave been submitted perceptible, it is inferred, that the effects to the examen of Messrs. Girard and depend chiefly ou the currents that Ampère. The subject treated of is the prevail at great depths. draining off water, by orifices made in Another object of the researches of thin sides of the receptacles containing M. Ampère, is the assimilation that he it. The Icarned Swede proves that makes of the magnet, and of the assemielastic fluids are, in this case, subject blages of circular parallel currents, to to the same laws as incompressible which he gives the name of clectrofluids, such as water.
dynamic cylinders. This assimilativ M. Ampère presented a continuation may be manifested, either by the way of bis Memoir on the Electro-Dynamic of experiment or by calculation. In Phenomena. Herein be has confirmed, employing the second method, we must by new experiments, certain results compare the poles of the magnetised deduced from bis preceding “Formulæ;" bars, and not their extremities, with he has also ascertained and announced the extremities of the electro dynamic two new facts. 1. That a voltaic cylinders; as, according to the espericonductor, placed very near a metallic ment of M. Ampère, the magnetic poles circait inclosed (fermé) but not.com. disclose the same properties as the es. municating with it, determines or draws tremities of the electro-dyuamic cyan electric current to it. • 2. Tbat a linders. This kind of proof, while it circular conductor, forming an entire confirms the results of experiment
, incircumference, has no action to produce presses the character of theory or a revolution round its axis, of an in. inductions derived solely from the ob closed conductor, be it of whatever scrvation of facts. form ; and that the same property occurs Two yoang and able naturalists hare in a conductor bent as the arc of any supplied what was wanting, in this recircle, whatever be the number of de. spect, in the Tract of M. Ampère en grees of that arc.
the identity of magnetism and electriTo this succeeds an investigation of city. Their memoirs were read to the the electric currents in the interior of academy, in the sitting of February 3, the globe, proceeding from east to last. That of M. Mont. Ferrand conwest, and the more intense as they are tains calculations relative to the mutual nearer to the magnetic equator, which action of a rectilinear conductor, and must then be considered as a medium of an assemblage of circular currents
, direction between all the currents; these situated in planes parallel to the dicurrents are considered, in all the cir- reolion of this conductor. Assumin cumstances of motion that they would the value or proportion assigned by produce on conductors, whether hori. M. Ampère, to the action of iwo ele. zontal or vertical.
ments of electrical currenis, the auther The results collected, by this author, determines that which is cxercised are conformable to the numerous expe- by an indefinite rectilinear conductor
, riments already made; some by him. I. On an element of electrical currcat. self, others by M. Delarive, all of which 2. On a circular current. 3. On an tend to shew the action that the earth assemblage of similar currents, perpef. exercises on mobile voltaic conductors. dicular to a right or curved line, passie, The author has thus completed the through their centres. When ibis is a theory of action which he had disco. right line, the calculation reproduces vered between two conductors, and also the law discovered in 1820, by M. Bist: that of the influence of the terrestrial and confirmed by the experiments path
Jished, in the same year, by, M. Pouillet. the views of administration.
M. Gay. If the line is a circumference of a circle, Lussac has drawn up tables, that for we then find one of the resulls of the science and minute detail become the experiments of Messrs. Gay-Lussac surest guide that rulers can follow in and Welter, on a steel ring magnetised, the collection of the revenue. A meny the process of M. Arago. If the line moir of M. Francoer, on this subject, of the centres is only a curve, with two and another by M. Lenoit on areomebranches syinmetrical, with respect to a ters, have honourable mention in the plane passing through the coniluetur, report of the commission. The latter inc analysis leuils to a resuit confirmed memoir may be considered as an exby recent experiunenis.
cellent chapter of a treatise on physics; The second circular memoir is that of but the author has not taken up the M. F. Savary; sonic account of it has experimental part of the question. aiready been given in the Revue En. M. Desprciz has applied himself to cyclopedique.
consider the conductibility of bodics, Never was any discovery prosecuted that is, the greater or less facility with with more zeal and success than that which licat penetrates them, and spreads of (Erstedt, on the analogy between the through their interior. He has found electric and magnetic fluids. Three that, in their relation to this property, years bave bardly clapsell, and the the following bodies or substances are science has already arrived at certain in the order that experiment has ascertheories, founded on facts, numerous tained, commencing with the highest and well analysed; also, at methods of degree; copper, iron, zinc, tiv, lead, calculation which would, alone, produce marble, porcelain, and brick-clay. The new discoveries.
report on this labour was drawn up by While the knowledge relative to elec- M. Fourier. The results obtained by tricity and magnetism is acquiring M. Depretz are pronounced by the comdaily accessions, the science of light missaries to be every way worthy of the and optics is advancing with rapid academy's encouragement; and that the stops. M. Fresnel has presented several physical sciences, several arts, and the memoirs, the object of which is to ex- oeconomical processes, as to the distri, press the general laws of double re. bution and use of fuel, would be benefraction; -also to discover the laws of fited by their publication. a new kind of polarisation, to u bich he of three comets observed in 1822, has given the name of circular polari- the first was discovered by M. Gambart, sation; also, to prove directly, that glass to whom we owe, also, the observation compressed, causes light to undergo a of two others at Marseilles. M. Pons double refraction; and lastly, to examine was the first that discovered the other the law of modification impressed by two. The Revue has already noticed a total reflection on polarised light. that comet wliose revolution was deter, These researches are connected with mined by M. Euke, and which has been the theoretic notions that M. Fresnel, designated as the comet of a short and several other writers on pliysics, period; it will hereafter, no doubt, re. have adopted, respecting the nature of ceive an appropriate name, like the light. They consider its action as other bodies of our system. operated by vibrations extremely ra- M. Gambey presented to the Acapid, propagated in elastic mediums. demy two instruments, constructed on From this opinion not being generally new principles, 1. A compass of decliadmitted, some dissensions bavc arisen nation; and 2, an heliostat, Witb rein the republic of sciences, though, spect to the invention and execution of from habii, more peaceably disposed astronomical instruinents, M.G. is, at than that of letters.
present, the first artist in Europe. The minister of interior had desired M. the Abbé Halma, translator of the the academy 1o examine afiesh the Almagest, is now publishing a French question of areometers, and compare translation of Ptolemy's “ Manual the respective methods proposed, so as Tables," hereby rendering a new service to determine with precision, by means 10 astronomy. He is also prosecuting of that instrument, the specific weight Enquiries on the Zodiack of Deuof liquids. M. Arngo, reporter to the derah,” and professes to prove that it commission charged with this labour, does not reach higher than the year has retraced some very accurate expe- 364 of the Christian æra. riments already made, by M. Gay- M. Coqnebert Montbret, reporter of Lussac, therein completely answering the “ Commission of Statistics,” after MONTHLY Mag, No. 387.
announcing the prizes decreed, notices once, there is reason to fear that facts the “Statistic Researches” of M. de will be inaccurately observed, and inChabrol, relative to the city of Paris, perfectly described. It has been ho and the department of the Seine. The therto believed, that the combination of rest of this work will shortly appear. chlore with percarbonated hydrogen,
Mention is next made of works re- contained cqual portions of these two lating to the colonies. M. de Jonnés substances. "M. Despreiz bas shows has commenced the publication of some that the volume of chlore is only half u useful memoirs on the “ Antilles ;" they that of the percarbonated hydrogen. are intended to complete the “ Natural M. Dulong, recently admitted into History of Guadaloupe and Martinico." the academy as a member, bas made some Certain other works have been collect- new discoveries on respiration, and on ing documents on the same islands; the causes of animal heat. He has were this plan extended to French found that the volume of carbonie acid, Gniana, and our establishments in the formed in the act of respiration, was Indian ocean, our colonies would be always less than that of the absorbed better known than many parts of the oxygen; experiments show it to be by interior of France.
one third, in birds and carnivorous quaM. B. dc Chateauneuf produced a drupeds, and by one tenth in the “ Memoir on the Mortality of Women, herbivorous. He has, morcover, rearrived at Ages from Forty to Fifty.” marked, that there was constantly so lo this he proves by evidence, that ap- strong an exbalation of azote, that, pears undeniable, contrary to a received in herbivorous animals, the volume of opinion, that the mortality of men is air expired surpassed that of the air ingreater at this period than that of wo- spired, notwithstanding the diminution mon. This consequence has been drawn of volume of the carbonic acid gas. from observations made in places ex. And, lastly, he has found the portion of tremely remote, and in very different heat, corresponding to that of the acid, climates; in the south of France, in the to be scarcely half of the total heat north of Russia, and in the intermediate yielded by the animal, unless it be carcountries.
nivorous; and that, in herbivorous A memoir of M. de Jonnès, on the kinds, it does not reach three quarters extent of lands susceptible of cultiva- of the same quantity. From these pretion in the French colonies, makes it mises, M. Dulong concludes that there plainly appear, that even one-third of remains some other cause, different the lands as yet not cleared, put into a from the fixation of oxygen, to account state of cultivation, would furnish sup. for animal heat in its totality. plies, not only for the consumption The loss sustained by the academy, in and manufactures of France, but for the death of M. Haüy, gave reason to exportation.
apprehend that the public would be de Messrs. P. Duchatelet and P. de prived of a complete edition of his Contreille, medical doctors of the fa- works, which the professor was preculty of Paris, have published some paring. Five volumes had already apRemarks on the River Bièvre. About peared, and the impression of the sixth the year 1790, the improvement of the and last is now proceeding, under the course of its waters, so as to render its inspection of M. Delafosse, pupil of M. banks more salubrious, had formed the Haüy, and selected, by him, to cosubject of an interesting publication by operate in his labours. M. Hallé. A considerable part of the M. Constant Prevost, a skilful natopopulation of the Faubourg St. Mar. ralist, a pupil of M. Brongojart, has ccau are daily employed on its banks, traced the geological traits of Nor. or in the vicinity, the importance of mandy and Picardy, from Calais to whose establishments would be greatly Cherbourg. At the two extremities of augmented, if the banks were lined with this line, nearly eighty leagues in extent, a wall of masonry, if a pavement were we find rocks of a similar character; laid down on the soil, if toll.gates were these rocks appertain to the primitive removed, &c.
soil; and, in some measure, form the In chemistry, facts are, progressively, borders of the immense basin, in which accumulating, so as, in time, to form a are deposited the rows or shells of the general theory that may include them, posterior eartbs. The middle of this in all their relations, and reveal, as far basin is pretty near Dieppe; there we as it is possible, the causes and laws of perceive, only, such as are the most sutheir action. In such a state of the sci. perficial, and they are almost all bori.
zontal. The intermediate shelves rise found to be buds. These disappeared,
M. de Humboldt is publishing the
tables. M. Dupetit Thouars considers the M. Dupetit Thouars bas presented flower as a transmutation of the leaf, and the commencement of an History of the of the bud that depends on it. His ex- Plants of the Family of Orchis. This periments on tbe juice of vegetables, forms part of a Flora of the Isles of present facts which seem no further France and Bourbon, which M. D. T. connected with that substance than as it has been long employed upon. is an assemblage of vegetable fibres, Several physiologists attribute the such as would be no less observed in faculty of absorbing exclusively to the other assemblages that have not the lymphatic vessels; some others, bowproperties of the juice. It is generally ever, allow it also to the veins, for all supposed that a tree, deprived of its that is not chyle. This question has bark, loses its power of vegetation. been, of late, the subject of renewed M. D. T. hias peeled trees, for three discussion. M. Srgelas has communiyears together, and they have sustained cated to the academy, and repeated, no injury. He thinks the elm endures before its committee, some experiments, this mutilation the best, but the oak de- which not only confirm, in general, the cays under it. A young peeled elm absorbent faculty of the veins, but produced, at first, some protuberances prove, also, that certain substances aro that took a greenish tint, and were soon only absorbed by those vessels, or, at