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vations of direct measurement of these volumes that I can find, and I find that the mean is 2.125. From theoretical grounds, I believe that more accurate experiments and observations will prove that the decimal fraction of an eighth must be struck off, and that the true proportion is represented by 2. Certainly 2 is the number given by the most accurate of the ten observers. But now to my verifications. I measured the length of the common fibres in the hearts of a great number of oxen, and I find it to be 10.875 inches. I measured the length of the fibres that go round the left ventricles in the same hearts, and I find as the mean of many measurements 8-625. Well, I suppose there is no one present here who is a good enough arithmetician to tell me at sight what the ratio of the cubes of those numbers would be. I have cubed the numbers, and their ratio comes out 2.004. I believe that to be a remarkable result, and to entitle us to assert that the principle of least action applied to the problem of the heart, is capable of solving it a step beyond what it has been solved, and bringing us within reach of the knowledge of one more of the wonderful laws the Creator. How it would rejoice the soul of the great Kepler if he had known that the ratio of the length of the fibres in his own heart was in the proportion of cube root of 2 to 1! Divine Geometry! Queen and mistress of philosophy, thy right to rule the sciences shall never be disputed!"— British Medical Journal for June.

Dynamics of Nerve and Muscle.-From the "British Medical Journal” (which contained an able review on it) we learn that Dr. Radcliffe has published his views on this subject. We have not seen the book, however, which is published by Messrs. Macmillan. Hence we can do no more than announce the fact of its publication. It is to be regretted that Messrs. Macmillan do not send out their books more freely for review. We have had to write for at least three or four of their recently published works. We have no care for the interests of a publisher, but we do not consider that an author is fairly served by the negligence of his publisher in regard to sending out his book for review. A lesson might well be taken from the American publishers in this respect.

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Dr. Lionel Beale a Baly" Medallist.-The "Baly Medal" of the Royal College of Physicians, London, has been awarded to Dr. Lionel Beale, and was presented to him immediately after the termination of the Harveian Oration.

Death of Von Niemeyer.-We regret to notice the decease of the distinguished Dr. Felix von Niemeyer, author of the well-known work on the Practice of Medicine, which has met with such a remarkable success in England and America through the translation of Drs. Humphreys and Hackley. We have no particulars of Niemeyer's case, except that he had recently returned from France, where he had been engaged in studying typhus and dysentery in the army. At the time of his return he was sick, but his illness was not believed then to be of a serious character.

Todd and Bowman's Physiology.—The second part of the new edition by Dr. Beale, F.R.S., has made its appearance. It is devoted to the consideration of fibrous, elastic, and connective tissues, cartilage, bone, and fat. It is of course a very valuable work, and we wish it were completed by the present editor, who is certainly somewhat slow at his work.

METALLURGY, MINERALOGY, AND MINING.

The Manufacture of Steel.-Mr. David Forbes' usual quarterly report on the mining and metallurgical resources of the several States of Europe, gives us most valuable information. In fact, it considerably lightens our task, for it gives in a condensed and thoroughly comprehensive form, everything that has been done for the quarter. We find it stated that M. Aristide Berard has recently introduced into practical operation, at Givors, in France, a process for the direct conversion of pig-iron into steel, for which, among other advantages, he claims that it effects a partial purification of the iron, by eliminating the sulphur, phosphorus, arsenic, &c.; at least, to such an extent, that commoner brands of pig-iron, which by no process at present known could be used, may be employed for making steel suitable for the manufacture of rails, tyres, &c.; and that, by the combined action of air and gas, alternate oxidising or reducing effects may be obtained at pleasure, so that the decarbonisation or recarbonisation, and consequent uniform nature of the product may be regulated, whilst at the same time the waste is reduced to a minimum. The main features of the process arethe conversion of the fuel employed into a gaseous state, the use of a jet of superheated steam in so doing, and the employment of a peculiarlyshaped converting furnace, in which, from three to five tons of cast-iron is treated at a time, the charge being run into the moveable bed of the furnace, in the molten state, direct from the blast furnace or cupola. Spiegeleisen is added in the operation, and the waste is stated to be not more than from seven to eight per cent., whilst the operation is said to require only from one hour to one hour and a half. The process has been fully described in a pamphlet, published by M. Berard.

Anthracite Coal Trade of Pennsylvania.-Mr. Peter W. Sheafer, a wellknown engineer at Pottsville, Pa., has prepared a diagram, which is published in "Silliman's American Journal," exhibiting the progressive development of the anthracite coal trade of Pennsylvania. It embraces the period of fifty years, from 1820 to 1870, and an accompanying table gives in detail, for each year, the yield of anthracite of the four great subdivisions of the anthracite region, the Lehigh, the Schuylkill, the Wyoming, and the Lykens Valley, Shamokin, &c. We take the export in tons, for the years below specified, from the table:

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998,839 15,849,899

1870 3,172,916 3,853,016 7,825,128

The Schuylkill trade began in 1822, with the exportation of 1,480 tons; the Wyoming, now twice the largest, in 1829, with 7,000 tons; the Lykens Valley, &c., in 1839, with 11,930 tons.

Tuddling by Siemens' Gas Furnace.-Mr. Forbes' Report states that in the

"Preussischer Zeitschr. f. Berg. Huetten u. Salinenwesen," 1870, p. 145, will be found an extremely interesting paper by Dr. Kosmann, in which he gives the results of a comparison between the effects and relative economy of puddling in the ordinary manner, and when done by Siemens' regenerative gas puddling furnace; although short, the space at command will only allow of our giving the conclusions arrived at, which are (1), that the Siemens' furnace is to be preferred in all cases where an extremely high heat is required, and where the fuel is of bad quality and unsuited for producing sufficient heat when consumed in the ordinary way; (2) whenever a fixed temperature or a certain quality of flame is required for any length of time; (3) when no use of the waste heat of the flame (as for heating steam boilers to drive machinery) is required. And, in addition, there is less waste and also somewhat less loss of iron in the slag with the Siemens than with the ordinary furnace, as may be seen by a comparison of the chemical analysis of the respective slags.

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The amount of phosphorus or sulphur eliminated in the slag is about the same in both instances. If, however, the fuel is of good quality, and the waste heat is employed for raising steam, then there appears to be little, if any, advantage in the employment of the Siemens furnace, which is known to be extremely costly, both in original construction and in subsequent repairs.

MICROSCOPY.

Sacs in the Tibia of a Flea.-A very long and somewhat important paper has appeared in the Quekett Club "Journal" for July, on the above subject. The function of these sacs, in the author's opinion, is somewhat peculiar. He says that the action of the contractile sac of the upper tarsal joint is first, by slow distension, to become filled with air, the membranous sac of the tibia simultaneously collapsing. When fully distended, the tarsal sac suddenly contracts to about one-fourth its previous diameter, when at the same moment the membranous sac of the tibia becomes fully inflated. This rhythmical, alternate movement sometimes proceeds, regularly, at the rate of two or three pulsations in the minute, but this is not always the case, as he has frequently found that it is suspended for longer or shorter periods, and in many specimens it is altogether wanting. Believing that

these remarkable organs have not hitherto been observed, he has devoted much attention to them, and he thinks he is justified in expressing the opinion that they probably serve a very important and hitherto unsuspected purpose, in the respiratory system of the animal, and further, if he is right in his conjecture, that similar organs will probably be found to exist in many other insects. He thinks it possible, then, that these contractile sacs serve the purpose of pumps or syringes, by means of which air is drawn through the external orifices or spiracles, and propelled through the minute capillary vessels of the tracheal system.

An Immersion Paraboloid is described by Mr. B. D. Jackson in the "Journal of the Quekett Club" for July. It is formed of a solid paraboloid of glass, ground to a different curve than the dry form, and instead of having its emergent surface hemispherically hollowed out, it is left nearly flat, a very slight concavity only being given. This concavity is so slight as to be hardly perceptible, but it is intended to permit the slide in contact with it, by means of the water film, to be moved to and fro without danger of scratching the glass top of the illuminator--no very difficult thing to do, in spite of the apparent hardness of the substance. The stop to prevent direct rays passing into the microscope is cemented to the lower surface of the paraboloid. The object (Eupodiscus argus) is shown by a quarter-inch binocular with a black field; the angle of the object-glass being about 110°, a result he has not been able to attain so satisfactorily by any means previously employed. There is no loss of light by reflection from the lower surface of the glass, since the rays pass almost in straight lines from the curved sides to the focus. The ordinary test diatom slide, when mounted dry on the cover, as usual, presents a curious appearance, the field being dark, with a small spot of orange-brown light, occupying about one-fifth of the diameter, the spherules, however, being shown distinctly. He has not been able as yet to use this illuminator with higher powers, the fog surrounding the object unpleasantly.

The French Erecting Prism is a Camera Lucida.-The July number of the "Monthly Microscopical Journal" contains a letter, in which the writer asserts most positively that this prism answers the purpose of a camera lucida.

The Degeeria Domestica, or Speckled Podura, is, according to Mr. Wenham ("Monthly Microscopical Journal," July), when shown opaquely under ath or upwards, a specially beautiful object. The scales are apparently much thicker than in other species, and the ribbings or !!! markings are of a reddish-brown colour-not beaded, but slightly constricted at regular intervals, like the short antennæ of some insects, and in the deep intercostal spaces there are numerous thin septæ, or transverse bars, very fine and distinct, of a greyish tint. Both these and the slightly "varicose" spaces on the ribs may be displayed in the form of beads, by dodging the illumination. Where practicable, some form of opaque illumination should always be employed for verifying the structure of these objects, for we are in this case quite free from the errors of diffraction, which more or less accompany objects seen by transmitted light, and cause an indistinctness of outline.

The "Wolf-rock" under the Microscope.-Mr. S. Allport, in the "Monthly Microscopical Journal," says that, when examined by the eye or simple lens,

the rock is seen to consist of a yellowish-grey compact base, in which crystals of clear glassy felspar are imbedded; they exhibit no striæ; their fracture is sharp and splintery. A thin section examined in polarised light with crossed prisms exhibits a beautiful group of crystals of felspar and nepheline porphyritically imbedded in a fine-grained matrix composed of minute crystals of nepheline, felspar, and hornblende; when cut very thin, the hornblende alone exhibits colours, the hexagonal sections of nepheline being black, the rectangular white; the felspar is also either dark or light, and the general appearance is that of a mosaic of dark and light stones interspersed with small brilliant-coloured crystals of hornblende; the whole forming a matrix in which the larger crystals are set. In thicker sections the felspar and nepheline display fine colours, but the minute structure is not so well seen.

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PHYSICS.

A New Key for the Morse Printing Telegraph was described to the British Association at Edinburgh by Professor Zenger. He said that, at the Norwich meeting, he had had the honour to show a new automatical key for the Morse printing telegraph, which printed three different signs-viz., a point, a short line, and a longer line. That arrangement restricted the telegraphist to a certain speed, but he had constructed the key now shown in order to allow a clever telegraphist to obtain the highest speed attainable. He showed a model, and explained it in detail. The rate of velocity was indicated by a small bell sounding as often as the cylinder revolved. By the mechanical arrangement, whatever the speed of the paper and the clockwork moving it, the relative length remains unalterably the same. On the working instrument, the printing apparatus with its rollers for the paper sheet is attached to the key, forming only one apparatus together. By using three signs, the combination of 1, 2, and 3 elements gives 39 signs. This will do for all letters, figures, and phrases commonly used, and spare nearly 30 degrees of space, and therefore of time of transmission. In a brief discussion, it was said that the adoption of Professor Zenger's apparatus would do away with the mistakes now so often made by the doubting whether the short line meant a line or a point.

The late Professor Payen.-Physics has lost one of its great masters through the death of Payen, which occurred a few months since. "Les Mondes" of June 29 contains a short account of his life. In 1824 he was the first who pointed out the rational method of applying manures in agriculture, and about the same time brought forward the theory of the decolouration of liquids by animal charcoal, also suggesting the use of the residues of sugar-refining (scums which contain more or less animal charcoal along with other substances) in agriculture. In 1830 he laid the foundation of the proper valuation of manures, according to their richness in nitrogen. The late author's exhaustive researches on amylaceous matter settled the exact structure, mode of formation, and the derivation of dextrine and glucose from starch; the existence of diastase, also, was first pointed out by the deceased. Prof. Payen, very well known, also, among a

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