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Organic Origin of Tripoli Stone.

Ecole des Mines or in the Jardin'des Plantes, nothing is to be distinguished but fine equal-sized grains of silica. The stone from Bilin is of a clear grayish-yellow, laminated, presenting all the appearance of a very modern deposit, and entirely composed of organic remains; these are cylindrical tubes formed by articulated rings, which with numbers of detached rings are found simply aggregated together without any cement or interposed matter; the rings are of various magnitudes, from the to the 100% of an inch in diameter, their average altitude being about half their diameter; they may be discerned by means of a single lens, magnifying 70 or 80 times. These fossils are evidently organic remains, but in form they have no resemblance to the baccilaria, which are prismatic. From what M. Dufrénoy told him concerning the Santa Fiora tripoli, which is also a recent deposit, M. Dujardin conceives that analogous fossils will be discovered in other siliceous friable deposits belonging to the tertiary formations; but nothing of the kind is perceivable, even in the pulverulent siliceous deposit accompanying the Menilites of the Paris basin.

M. EHRENBERG has recently made the remarkable discovery that the siliceous rocks, apparently homogenous, friable and even laminated, and which are known by the name of Tripolies, (polier schiefer of Werner,) are entirely formed of distinct remains, or rather skeletons of infusorial animals of the baccilarian order, and of the genera cocconema, synedra, gaillonella, &c. These remains, which have perfectly preserved the form of the silicified bodies of these infusoriæ, may be seen with the greatest distinctness in a microscope, and may be readily compared with the living species which have been observed and accurately drawn by M. Ehrenberg. In many cases there is no appreciable difference; the species are discriminated by the form, or more distinctly, by the number of the transversal septa which divide their minute bodies; and M. Ehrenberg, who has succeeded in counting them, has found the same number of these septa in the fossile and in the living species. His investigations have been made on the tripolies of Bilin, in Bohemia, of Santa-Fiora, in Tuscany, and on those of Ile-de-France Chalk taken from certain parts of and Francisbad. It is only necessary the cretaceous formation, has been found to take a sample of one of these tripo- to consist of the débris of minute corals, lies, that of Bilin for instance, to grate foraminifera, and valves of a small a little on a plate of glass, to temper the entomostraceous animal resembling the dust with a drop of water, and then to see cytherina. It is probable, therefore, by means of a good microscope, thou- that organic agency has been more exsands, or rather millions of remains of tensively employed in the formation these animalcula; the greater number of the crust of the globe than has of the species are fresh-water, but there hitherto been supposed; the last-menare also marine, especially in the tripoli tioned fact giving additional support to of Ile-de-France. M. Dujardin enthe hypothesis that lime is a product of deavoured to verify this singular dis-organic origin. We hope that the nacovery; his attempts to do so by means of the tripolies of commerce, and of many collections, were totally fruitless; but fortunately, at the Ecole des Mines, he met with the genuine Bilin tripoli. M. Dufrénoy pointed out to him the difference between this pseudo-tripoli, which is a fresh-water depôt formed in recent geological æras, and tripolies, properly so called, which are either volcanic rocks, or carbonaceous schistus of a very ancient formation, modified by igneous agency, as may be observed in that of Poligni, near to Rennes. In these tripolies, in that of Venice, which is yellowish, and whose origin is not known, as well as in many others, specimens, of which are to be seen in the

turalists of our own country will hasten to ascertain and confirm the truth of this singular discovery.

Hypotheses respecting Aurora

Borealis.

OUR readers are aware that at the late meeting at Bristol, Mr. Herapath described the appearances presented by a remarkable Aurora he witnessed in November last, from which he came to the conclusion that that phenomenon is merely electricity passing off from a charged cloud, in the act of dissolving in air that can take its water, but not its electrical fluid, which consequently becomes visible.

Professor Joslin. of Schenectady, U.S. has recently published a paper on the subject of Aurora, and, from a number of observations, comes to the conclusions, That the temperature of the air is falling, and the atmospheric pressure increasing, on the day in which an Aurora appears; that, generally, after Aurora, the atmospheric pressure decreases, temperature rises, and water falls as snow or rain within two days; that the air at the earth's surface, if not saturated with moisture at the time of an Aurora, is much nearer than usual to that point.

an

Convenient numerical Expression of the

Welfare, &c., of a Nation.

M. DUPIN, the present President of the Académie des Sciences, in his "Researches on the Influence of the Price of Corn on the population of France," read in May and June last before the Academy, has come to the conclusion, that it is untrue to assert that the abundance or scarcity of the means of subsistence, acts as the principal and predominant cause, in the amount either of births or of deaths in the French nation, and that "the years in which the greatest numbers of marriages take place, are not those in which the prices of provisions are the lowest."

It will be easily perceived that these results are conformable to Mr. Herapath's hypothesis. Professor Joslin, Professor Joslin, however, proposes another equally de- He considers it as demonstrated, that serving of attention, that Aurora is "the fortuitous causes brought into the result of crystallization of the va- action by intemperate seasons, compours of the atmosphere. The follow-mercial fluctuations, and the vicissitudes ing are the principal steps in the argu- of human affairs, produce at the present time much greater inequalities in deaths, marriages, and births, than the extremes of abundance or scarcity.

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Light is given out during the process of congelation, and since it appears that the state of the atmosphere is favourable to the deposition of moisture, and to its crystallization from the decreasing temperature, it is hence possible, if not probable, that the light is the result of this action. If the molecules of crystals have a peculiar kind of polarity which governs them in their arrangement, they may be also affected by the magnetism of the earth, and thus would be produced the columns which Aurora usually presents, their fluctuations arising from the unsteady nature of the atmosphere and the continual repro-truth in the following manner:duction of light from the crystallization of new quantities of vapour.

'It is not, then, necessary or useful," he continues, for Frenchmen to extol the desolating doctrines of Malthus, which deprecate the increase of the human race by the less opulent classes." And he rejoices "that Science is able to demonstrate that the speculative and systematic theories which freeze up the human heart and wound the natural feelings, are contradicted by facts, and have no foundation in experience.'

It has also been observed, that Auroras are most common during the months of November and December, and that when they consist merely of a bank of light, like the dawn, the magnetic needle is but slightly affected; but that when beams or streamers are formed, the disturbance of the needle seems to indicate a more active magnetic energy. There is no contradiction between the hypotheses of these two gentlemen, and as all theories are only regarded by true followers of inductive science, as guides in the collection of new facts by which the real explanation of a phenomenon may, in time, be arrived at, meteorologists will have new incentives to extended and accurate observations.

He then proceeds to take advantage of the newly-discovered and welcome

"The minute variations in the annual amount of births, marriages, and deaths, even when great alterations have taken place in the price of corn, have led me to seek for a function of these three social elements, which should exhibit these variations far more sensibly, by correcting, through the means of each other, the irregularities produced by the numerous unforeseen, accidental, and transitory causes.

"Every general cause of public prosperity multiplies, on the one hand, the births and marriages, and diminishes the deaths on the other.

"If we suppose a population so situated as to remain in the same social and physical circumstances, and which should at once be doubled, tripled, quadrupled, &c., the births, marriages and deaths, would be similarly doubled,

tripled, quadrupled, &c.; consequently, the proportion of the births and marriages to the deaths would remain constant, whatever might be the increase of the population.

value of the Functions of Vitality is 0.5937.

"The second, a period of high prices; the mean of the prices is 22 fr. 48 c., and that of the Functions of Vitality,

"I have taken the mean of the two 0.6092. following proportions:

Births

Marriages

Deaths. Deaths.

and I have called it the Function of Vitality.

"This Function is, as has been seen, independent of the total number of the inhabitants. This, in the existing state of things, offers a great advantage; for the fact is, that up to the present day, the census of the whole [French] population has at all times been imperfect, but the Registers of the State have given, with great accuracy, the annual number of the births, marriages, and deaths.

"The very evident variations which the Function of national Vitality undergoes at the end of a certain number of years, are the mathematical expression and the sure demonstration of the great changes which have affected the welfare of the people.

"In the following Table are given the Price of Wheat, and the Function under consideration, obtained as above, for each year 1817..... 1830. The years, &c., are arranged into groups, and the fifth and sixth columns contain the means of each group.

Comparative Table of the Prices of Wheat, and the Functions of Vitality, for fifteen years, arranged according to the Prices, beginning with the highest.

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"The third, a period of intermediate, or moderate prices; mean price, 18 fr. 05 c.; mean of the Functions of Vitality,

0.6168.

"The fourth, a period of the lowest of the Functions, 0.6097. prices; mean price, 15 fr. 69 c., and that

"The Function of Vitality of the fourth, or lowest-price period is, as may be observed, less than that of the third, or moderate-price period.

most favourable to the welfare of the "It would, therefore, appear to be nation in general, that the price of corn should fluctuate among the intermediate 18 fr. per hectolitre of wheat. prices of 1 fr. above, and of 2 fr. below,

"Before a further extension of the

conclusions which may be drawn from similar considerations, it will be necessary to accumulate observations, and to proceed with great circumtemptation to spection, so that there may be no hazard consequences,

which futurity and facts more carefully collected and established, may not con

firm.

"It would be desirable that the value of this Function should be inserted every year in the Annuaire du Bureau the Summary of the Population-Tables des Longitudes. It might be placed in which have been given-1817...1835.

"This new element would imme

diately attract attention to the degree of welfare or distress enjoyed by the population of France in each of the years so furnished.

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'Statesmen, statisticians, and medical men, each in his own peculiar sphere, might then study the causes of the variations indicated by this element, and by this means, much valuable assistance would be afforded to such as may attempt to appreciate the causes which are favourable or otherwise to the amelioration of the condition of man.

"Fifty years ago, the mean value of the Function of Vitality, calculated upon an average of fourteen years, amounted to 0.5403.

"This same Function, calculated on an average of fifteen years, from 1817 to 1831, gives a mean of 0.6103. The

superiority of the latter number is the expression of the immense advance in the welfare of the French people in the course of the last half-century.

"It is greatly to be wished that the same Function should be carefully calculated for other countries, in order that their welfare and prosperity might be accurately compared by one and the same scale."

Visible Sparks from the Torpedo. No one up to the present time has yet perceived the electric spark in experiments made on the torpedo. M. de Humboldt, even in the native country of the gymnotus, did not succeed in observing it. Walsh, unsuccessful in numerous attempts to obtain it from the torpedo, succeeded, in August, 1776, in rendering the spark visible, in operating with a gymnotus. Fahlberg, Ingenhousz, and others, have stated, that they have observed, at times, a spark during the discharge of the electrical eel of Surinam.

MM. Linari and Matteucci, in some experiments upon torpedoes, conducted with great care, have arrived at the most successful results. A letter, addressed by the latter philosopher to M. Arago, contains some curious details on the subject.

The author, in the first place, describes the apparatus by means of which M. Linari was able to obtain from a single torpedo as many as ten sparks in succession, every one very visible and brilliant. As far as M. Linari could ascertain, neither the size, the age, nor the sex of the animal made the slightest difference in the production of the spark. A small torpedo, of four inches and a half in diameter, furnished him with a long train of very brilliant sparks. They were also obtained from a torpedo which had been kept three days out of the sea, but then the brine of his tub was obliged to be perpetually renewed. The decomposition of acidulated water, and the permanent magnetizing of steel needles, were constantly obtained by M. Linari.

M. Matteucci, after describing his own apparatus, which differs but little from that of M. Linari, states that he, in the first place, verified the results of the latter experimenter, and then succeeded in obtaining, with the current of the torpedo, all the phenomena of the ordinary electric current.

"I came finally," says M. Matteucci "to the most conclusive experiments that I could have desired for the developement of the electric current in the torpedo. These experiments are always extremely difficult, from the feeble vitality of the animal when often irritated, and from the extreme care necessary to preserve it alive when out of the sea.

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By means of a very sensible galvanometer, I found that the current in the torpedo is constantly in the direction from the back to the abdomen. The former may be considered as the positive, and the abdomen as the negative pole of its apparatus. The discharge acts in the same direction in the two organs which are on the sides of the torpedo, the current is also obtained precisely the same, when one of the poles of the galvanometer touches the lower part of the right organ, and the other the back of that on the left, or inversely. The deviation of the galvanometer is increased, if instead of directly touching the skin of the torpedo with the platina poles, they are brought in contact with slips of metal, previously placed on the two surfaces of the fish; but a continuous current is never produced, however much the organ may be compressed. The discharge is generally produced with certainty, if the animal is bent so as to render the abdo men slightly concave. If the skin with which an organ is covered be removed, the deviation diminishes in intensity, but always occurs again when the animal discharges. When it ceases to discharge, not the least trace of the electric current can be detected in any part of the organ. The deviation is also altogether suspended, when the two extremities of the galvanometer touch the back, or the abdomen, of the fish If of the three at the same instant. nervous bodies which run from the brain and penetrate an organ, two are cut away, the discharge still continues, but it immediately ceases on cutting away the middle one. The other organ, if left entire during these operations, continues to act without interruption."

Fluorine.

IT is not commonly known in this country* that this simple substance has been obtained in its separate state. M. Baudrimont, in a dictionary of general See Vol. I., p. 294.

United States New Patents' Act.

physics, published in December, 1834, indicated its general properties in these THE Bill for the establishment of a terms: "Fluorine is a gaseous body of Patent Office in the United States, and a deep brownish-yellow; its odour is similar to that of Chlorine, or to that of for placing this branch of the administration under the control of the legisburnt sugar; it does not act on glass; it deprives indigo of its colour, and lature, on a simple and rational system, combines directly with gold." M. Bau- intelligible to all, has passed into a law. drimont has recently obtained it by ("APPROVED, ANDREW JACKSON,") on It received the fiat of the President treating a mixture of fluoride of calcium the 4th of July last,-the Sixtieth and peroxide of manganese, with sulphuric acid in a glass bottle; the excess dence. The act is called an Act to Anniversary of American Indepenof one of the substances employed would produce either oxygen or hydro- promote Useful Arts, and we look with fluoric acid, and this last by its action envy on the title. Nothing could be on the glass would be changed into morable day on which it obtained the more in perfect harmony with the mesilicated-fluoric gas. His first method of extracting the fluorine, consisted in American "Royal Assent," and though we admit that the passing of such an Act decomposing fluoboric gas by means of the deutoxide of lead heated to red-richly deserved an anniversary of its ness, and he obtained fluorine but less pure than subsequently.

M. Pelouze has lately announced another mode; he decomposed fluoret of silver in water by means of chlorine, the result, according to M. Baudrimont, ought to be a compound of hypochloric and hydrofluoric acids.

A great difference is deserving of remark between the fluorine obtained by these processes and that which might have been expected to be the base of fluoric or hydrofluoric acids, so well known for its energetic action on glass, and which appears to be more deleterious than other hydro-acids.

We may hope, therefore, soon to be better acquainted with fluorine than

with fluoric-acid itself, which can neither

be prepared nor preserved in glass

vessels.

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own, yet, taking it as it occurred, what could possibly be more peculiarly impressive than the contemplation of the chief magistrate of a great nation, on the anniversary of that nation's independence, giving validity to an Act to priate subject for an historical picture promote the useful arts. A more approin the Washington Capitol can scarcely be imagined.

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From such a scene, if we turn our eyes national pride; here we see high offihomeward, what humiliation awaits our fees, and baffling every attempt made cial personages clutching exorbitant by our most enlightened and intelligent arts." Here we see delay, and manœuvre, countrymen to promote the useful and deception, successfully deferring, teresting to our native talent, and uniyear after year, a measure deeply inversally important to the national manufactures. Is it possible to contemplate unruffled this contrast between "the Old and the New Country?" In this, a fee of a few dollars on each patent, without a farthing from the government, maintains an office, in which qualified persons are in attendance to advise in cases of doubt, and to examine, and register, and exhibit all specifications, in which are provided scientific books, perio dical publications, models, and collections of machines, products, &c., all selected and preserved for the purpose of spread. ing accurate information on subjects. connected with patents, patentees, and patent-rights. In our country, nearly £30,000, perhaps more, has been paid.

* An Abstract of this Bill is given at p. 76 of the present volume.

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