The Magnetic Polarity of Rifles. Mr. J. Spiller has lately made some very interesting observations respecting the magnetic power assumed by rifles. He finds that all the long Enfield barrels of the arms in the possession of the volunteers of his company exhibit magnetic polarity as the result of the violent and repeated concussions attending their discharge in a direction parallel to the magnetic meridian. The Royal Arsenal range runs nearly north and south, and the rifles, when in use, are always pointed either due north or a few degrees toward the west—in fact, nearly in the direction indicated by a compass-needle—so that the repeated shocks brought about by the explosion of the powder may, Mr. Spiller thinks, be considered equivalent to so many hard blows from a hammer, which, as is well known, have a similar effect. Mr. Spiller goes on to say that the magnetic character appears to be permanent, which would not be the case if the gun-barrels were of the softest description of malleable iron; and the region of the breech is, in every instance, possessed of north polarity, since it strongly attracts the south pole of the compass needle. These effects should not be noticed at all, or only to an inferior degree, in arms ordinarily fired in directions east and west; and it is supposed that by reversing the usual practice, if it were possible, and firing towards the south, the indications of polarity would be changed.
Mont Cenis Railway.—In a paper read before the Institute of Civil Engineers, Capt. H. W. Tyler has fully described the results of experiments with Mr. Fell's locomotive, which has been adopted for surmounting the steep gradients and sharp curves of the Mont Cenis route. On Mr. Fell's system an intermediate or centre rail is adopted, against which horizontal wheels worked by the engine are pressed by springs, so as to yield any requisite amount of adhesion. The engine constructed for the Mont Cenis line is partly of steel; its weight fully loaded does not exceed 17 tons. There are two 15-inch cylinders working both the four coupled horizontal and the four coupled bearing wheels. The pressure on the additional horizontal wheels can be varied by the engine-driver at pleasure; during the experiments it amounted to from 2½ to 3 tons on each wheel, or 10 tons altogether, but provision was made for increasing this pressure to 24 tons if necessary. During the official trials, with a load of 24 tons exclusive of the engine, on an average gradient of 1 in 13, with curves of 2 to 4 chains radius, the speed of 6.65 miles to 7.46 miles per hour was attained in ascending. With a load of 16 tons the speed was 10 miles.
Fossil Man in the Rhine Valley.—In the Lehm of the valley of the Rhine, near Colmar, there is a marly deposit composed of a mixture of clay, fine sand, and carbonate of lime. It forms part of the diluvial beds, and in it M. Faudel has found a number of human and other remains. These consisted of shells, bones of a huge stag, teeth of Elephas primigenuis, and a human frontal and right parietal bone of a man of middle size. M. Faudel concludes that man was contemporaneous with the mammoth fossil stag and bison.
Tobacco Smoking Injurious to the Eyes.—In a recent number (February 15) of the Bulletin de Thérapeutique, M. Viardin describes two cases of serious eye affection (amblyopia) resulting from the habit of smoking. M. Viardin at once, on learning the habits of the patients, induced them to smoke a much smaller quantity of tobacco than usual, and the result was a complete restoration of vision in a few weeks from the date of their application.
Intermittent Fevers produced by Vegetable Organisms.—Some time since, we called attention to Dr. Salisbury's observations, tending to support the theory expressed above. More recently these ideas have been, in some measure, confirmed by Professor Hannon, of the University of Brussels. In 1843, says M. Hannon, "I studied at the University of Liege; Professor Charles Morsen had created in me such an enthusiasm in the study of the fresh-water algae that the windows and mantel-piece of my chamber were encumbered with plates filled with vaucheria, oscillatoria, and confervae. My preceptor said to me: 'Take care at the period of their fructification, for the spores of the algae give intermittent fever. I have had it every time I have studied them too closely.' As I cultivated my algae in pure water, and not in the water of the marsh where I had gathered them, I did not attach any importance to his remark. I suffered for my carelessness a month later, at the period of their fructification. I was taken with shivering; my teeth chattered; I had the fever, which lasted six weeks."
Origin of Petroleum.—Although nearly all geologists are agreed as to the organic origin of petroleum, a great many are of opinion that the rock-oil is the result of a natural distillation of coal. Professor Hitchcock, however, no mean authority, comes to a different conclusion. Admitting, with all who have carefully studied the matter, that petroleum is of organic origin, he says that, in his opinion, it comes from plants, and that it is not, as some have suggested, a fish-oil or a substance altered to adipocere. It does not appear to be the result of a natural distillation of coal, since its chemical composition is different from the oil manufactured artificially from the cannels, containing neither nitro-benzole nor aniline. Moreover, petroleum occupied fissures in the silurian and devonian strata long before the trees of the coal period were growing in their native forests. The nearly universal association of brine with petroleum, and the fact of the slight solubility of hydrocarbons in fresh, but insolubility in salt water, excite the inquiry whether the salt water of primeval lagoons may not have prevented the escape of the vegetable gases beneath, and condensed them into liquids.
Structure of the Liver.—Dr. Lionel Beale's opinion as to the structure of the vertebrate liver has been recently substantiated by the researches of Herr Hering. This histologist states that the liver is constructed like the other secreting glands. It is of the tubular type, with canals, anastomosing in every direction, and having a tendency to form a series of networks. Like other secretions, the bile travels along glandular canals surrounded by glandular cells. It is easy (he says) to observe this arrangement in the livers of vertebrates. Five or more cells are disposed in simple layers around the circular and minute aperture of a hepatic utricle seen in transverse section. This arrangement loses itself insensibly in that variety of structure in which there are no utricles properly so called. Occasionally may be seen four, three, or even only two cells, uniting to form a biliary canal. The Russian anatomist denies the existence of hepatic trabeculae of biliferous capillaries, and believes that the biliary cells are persistent. He looks upon serpents' livers as the only organs for minute inquiries upon the subject.
The Cometary Theory of Shooting-Stars—to whom does it belong?—The Abbé Moigno, who has broached this question, and who evidently feels strongly on the point, makes the following observations in our contemporary, the Chemical News, of March 15th: "In a quite recent note inserted on March 3d, in the International Bulletin of the Imperial Observatory, and on the 8th inst. in the Bulletin of the Scientific Association of France, M. Le Verrier resumes on the cometary theory of shooting-stars, and persists in attributing the honor of it to himself, without condescending to mention the name of Schiaparelli, whose letters, however, have been published in a journal of great authority, the Meteorological Bulletin of the College of Rome, issued under the superintendence of the Rev. P. Secchi, and were translated by the writer before M. Le Verrier had published a single word of his researches. We are really frightened by this system of organized cool-blooded appropriation, and more so by these lines, the effect of which has been even more coolly calculated: 'Sir John Herschel, who, along with his son, Alexander Herschel, has paid great attention to shooting-stars, gives his complete assent to the theory of the swarms of November.' Poor M. Schiaparelli! Happily the Astronomische Nachrichten have collected the necessary papers, and he will soon be in a position of having his revenge."
New Form of Telegraphy.—An invention for the transmission of despatches by an automatic electro-chemical method has been devised by MM. Vavin and Fribourg. Its object is to utilize all the velocity of the current on telegraphic lines. The Abbé Moigno, who has called attention to it in England, gives the following description of it: It consists in the distribution of the current through as many small wires, very short and isolated, as there are signals to be transmitted, all the while only employing one wire on the main line. Each of these small isolated wires communicates, on the one hand, with a metallic plate, of a particular form, fixed in gutta-percha; and, on the other, with a metallic division of a disc, which is also formed of an insulating substance. A group of eleven of those small laminae form a sort of cipher, which will give all the letters of the alphabet by the suppression of certain portions of the fundamental form. "Now," says the abbé, "suppose rows of these compound characters to be placed on a sheet of prepared paper of a metallic nature, the words of the telegram to be sent are written on them with isolating ink, leaving the other parts of the small 'stereotyped' blocks untouched. The consequence is that the current is intercepted at every point touched by the ink, and a letter is, imprinted on the prepared paper at the other end of the line where the telegram is to be received."