ABSTRACTS OF THE PHILOSOPHICAL TRANSACTIONS. on Sir Humphry's paper was entered" the journal books of the Society," for there certainly appears to be some dif 207 ference between the original and the abstract, as the following parallel pass sages will testify : "These results are best explained by con- "With a view to explain the non-transsidering the nature of the flame of combus- mission of heat through small apertures, the tible bodies, which, in all cases, must be author considers the nature of flame in geconsidered as the combustion of an explosive neral; and since a piece of phosphorus, or mixture of inflammable gas, or vapour and even a small taper, will burn in the midst of air; for it cannot be regarded, as a mere a large flame made by the combustion of alcombustion at the surface of contact of the cohol, he is of opinion that oxygen exists in inflammable matter; and the fact is proved the centre of all flame, forming an explosive by holding a taper, or a piece of burning mixture with the vapour, but which burns phosphorus, within a large flame made by solely at the exterior surface, because it is the combustion of alcohol-the flame of the there alone sufficiently heated to take fire.”— candle or of the phosphorus will appear in Abstracts, vol. ii. p. 36. the centre of the other flame, proving that there is oxygen even in its interior part."Phil. Trans., 1816, p. 116. It is assuredly rather strange, that the abstractor should have found words (we allude especially to the concluding ones of our quotation) at the time, which are not now to be found in the essay he professes to abridge, and which, moreover, throw rather a new light on the subject. There are also some omissions in the analysis of the same paper, which are not easily accounted for, and tend to shake that confidence in the complete fidelity of the " Abstracts," which is so essential to the existence of their reputation as "honest chronicles." This should, of course, have been avoided; for, once let the notion become current, that the Abstracts are not strictly faithful copies in miniature of their originals, and the utility of the work is at an end. This would be a pity, since the reduced "Transactions" must be a valuable acquisition in many places, where the voluminous work in full is not accessible. It is rather singular that most scientific miscellanies published in England, where the application of science to the useful arts, and the ordinary purposes of life, is carried to a far greater extent than in any other country on the face of the globe, are remarkably deficient in information of a corresponding practical nature. The observation will apply in all its force to these volumes, in which a much larger space is afforded to papers on such subjects as "the formation of fat in the intestine of the tadpole," than on the progress of the great conqueror STEAM. There is an exception to the rule, however, in the shape of an interesting paper on the improvements successively effected in the Cornish steamengines, by the late President, Mr. Davies Gilbert, which is well worth transferring to our pages: "The terms proposed by Mr. Watt, in virtue of his patent in 1769, which secured to him, until the year 1800, the receipts of one-third of all the savings in fuel resulting from the adoption of his improvements in the construction of the engine, rendered it necessary to institute an accurate comparison between the efficiency of his with former engines. A copy of the report drawn up on this occasion, in October, 1778, is given in the paper; but as the dynamic unit of one pound avoirdupois, raised through a height of one foot, had not yet been established as the measure of efficiency, the author, proceeding upon the data furnished by that report, calculates that the duty performed by Watt's engine, with the consumption of one bushel of coal, on that occasion, was 7,037,800. In the year 1793, an account was taken of the work performed by seventeen engines, on Mr. Watt's construction, then working in Cornwall,-their average duty was 19,569,000, which exceeds the performance of the former atmospheric engines, in the standard experiments, in the proportion of 2.78 to 1. Some years afterwards, disputes having arisen as to the real performance of Mr. Watt's engines, the matter was referred to five arbiters, of whom the author was one; and their report, dated in May, 1798, is given as far as relates to the duties of the engines, The general average of twenty-three engines was 17,671,000. Since that period, so great have been the improvements in the economy of fuel, and other parts of the machinery, that, in Dec., 1829, the duty of the best engine, with a cylinder of 80 inches, was 25.628,000, exceeding the duty performed in 1795, in the proportion of 3.865 to 1; and that of the atmospheric engine of 1778, in the proportion of 10.75 to 1."-Vol. ii. p. 393. 208 NOTES AND NOTICES. NOTES AND NOTICES. The apparent paucity in the numbers of the swallow tribe, which usually make their appearance about this time, has led many persons to remark that these our elegant, and it may be added, useful annual visitants, must have encountered, as a body, some mishap in their migrations, as the season with us has not been unfavourable to their early, nor, from any obvious cause, to their plentiful appearance.-Sheffield Mercury. The Poor Man's Music, as it has been happily termed by some one, is no where so much regarded and protected as in the Duchy of Nassau, where it is contrary to law to take bird's-nests: even those of birds of prey cannot be taken without permission from the keeper of the forests. For taking a nest of common singing birds the fine is 5 florins; if nightingales, 15 florins; if the nest be taken out of a garden or pleasure ground, the fine is doubled. What Dr. Johnson says of second-hand writers, may be applied with equal truth to second-hand inventors. "If I am ever found," he says, in his Preface to Shakspeare's Plays, "to encroach upon the remarks of any other commentator, I am willing that the honour, be it more or less, should be tranferred to the first claimant, for his right, and his alone, stands above dispute; the second can prove his pretensions only to himselfnor can himself always distinguish invention with sufficient certainty from recollection." A correspondent, who is connected with the brewing business, requests us to state, that if the "Subscriber" (No. 561, p. 96)," whose occupation as a brewer requires his getting up at all hours of the night, is desirous of a more simple and effica cious awakener than his alarum, and is disposed to pay moderately for much valuable advice, he will not only put him in possession of such as will enable him to pursue his avocation on much better principles than he is now doing, without ever having occasion to rise in the night, or earlier than six or seven o'clock in the morning, and finish early in the evening, but furnish him with much information beside, which the nature of his inquiries shows that he is not possessed of."-The writer's address may be obtained on application to the Editor.-We have received from another correspondent (Mr. Wm. Pearson, of Bishop Auckland) a description of an alarum, constructed by a clock and watch-maker of that place, which he (Mr. Pearson) has seen in successful operation, and praises for its extraordinary powers. We shall give it in an early Number. The "Construction for the Trisecting of an Angle or Arc," sent us by a" Professor of Mathematics," and author of an edition of Euclid on a new plan, does not trisect the arc exactly-it is but an approximation, which could be of no earthly use. A petition from Mr. S. R. Bakewell, of Manchester (the inventor of the very ingenious brickmaking machine, noticed in Mech. Mag. of May 14, 1831), has been presented to the House of Commons, in which he states, that he "has invented and wishes to put in operation a chemical and mechanical criterion for preventing and detecting forgeries, more difficult to counterfeit than any other plan or contrivance ever yet invented for that purpose;"-that it is "not applicable to banknotes only, but also to drafts, checks, bonds, wills, powers of attorney, stock, and other certificates ;"and that he believes it will, when brought into operation, put a complete and entire end to forgery." The petitioner prayed that a committee might be appointed to receive proofs of the efficiency of the invention; but this reasonable request has not, we regret to say, been complied with. 66 There is a patch of ground, at Nether Haugh, belonging to Earl Fitzwilliam, under which a bed of coal has been on fire for several years. Attempts have been made to extinguish this subterranean furnace, but without effect, and when or how it will end seems impossible to guess. Some years ago a number of the industrious inhabitants of the village of Greesbro, bethought themselves that what had seemed, and was in fact, a real evil, might be turned to advantage, and having obtained the land over the fire to be laid out in garden patches, it is from thence that for some time has been obtained the finest early potatoes which have been sold in the Rotherham and Sheffield markets. Sheffield Iris. Mr. John Vallance had a patent some years ago for packing hops in iron cases. If ever tried, what was the result? Any particulars relative to the method and the consequences would, probably, much oblige many others besides the inquirer.G. A. The "Problems in Practical Surveying," which Mr. F. wishes us to submit to our readers, present really no difficulty whatever. The second, for in stance, which he imagines can only be well solved with the help of fluxions, requires but a knowledge of common arithmetic. Here (for his private benefit) is our way of disposing of it: 96 x 828772, area of the fig. A B CD; 465 37.729 CM. Mr. C. Hyde, of Horsley, surveyor, desires we will acquaint our readers that he is about to publish a "New System of Plane Trigonometry," in which he will show how the case proposed by him in the Mechanics' Magazine, May 5, 1832, and all similar cases of surveying, may be solved by two statings instead of by four-which he alleges to be the usual practice. We suspect, however, that Mr. Hyde's system will not prove to be so "new" as he imagines so far, at least, as regards the cases in question. In all the respectable works on Trigonometry, with which we are acquainted, similar problems are to be found, solved by two statingsindeed, where the perpendicular altitude of the object only is required, we have never seen more than two employed. The work of Davis on Land Sur veying, which Mr. Hyde quotes in evidence of a contrary practice, we have not seen; but we have heard it indifferently spoken of, by very competent judges. From a series of experiments made by the Soci ety of Arts, it appears, that the dried seed-pods of the algaroba tree of South America (prosopis pallida), might form an excellent substitute for oak bark in tanning; the proportions of tanning power possessed by the two materials being as follows-algaroba 4.6, oak-bark 1. The "Description of a New Portable Blow-pipe" is intended for insertion. Communications received from Mr. WoodhouseMr. Halligan-Mr. Watson-G. L. R. The Supplement to Vol. XX., with a Portrait of William Symington, is now ready, price 6d. also Vol. XX., complete, in boards, price 8s. LONDON: Published by M. SALMON, at the Mechanics' Magazine Office, No. 6, Peterborough Court, between 135 and 136, Fleet-street. Agent for the American Edition, Mr. O. RICH, 12, Red Lion-square. Sold by G. G. BENNIS, 55, Rue Neuve, Saint Augustin, Paris. M. SALMON, Printer, Fleet-street. 210 IMPROVED ROSE-WORK, AND IMPROVED ROSE-WORK, AND "UNIVERSAL ROSETTE. Sir,-Having a wish to add to my turning-lathe some apparatus for rosework, and not approving, for several reasons, of that usually employed, I determined to try the oscillating frame, as described in the "Manuel du Tourneur," which gives the figured motion to the cutting-tool, instead of the object to be cut. I had nearly completed it, when my friend, Mr. Child (who is already known to your readers), saw it, and with his usual kindness and liberal feeling offered me the use of his papers and ideas on the subject, as it had occurred to him in earlier life. It appeared from them that he had invented this mode of producing figured work (the original drawings of which I have now in my possession), and had substituted for resettes a simple means of producing an infinite variety of figures. In conformity with his instructions I went to work, and the result of my labour is such as to give me an impression that this mode, when generally known, will supersede that hitherto in use. As many of your readers, who are interested in fancy turning, have not access to the "Manuel du Tourneur," I shall describe the oscillating frame as I have altered it to meet Mr. Child's ideas. The drawings to which I shall refer, in the course of my description, are, fig. 1, an end elevation; fig. 2, a side eleva tion; fig. 3, a plan (all these three of size); fig. 4, section of Mr. Child's universal rosette, half size; figs. 5, 6, and 7, auxiliary portions of the apparatus. A strong bar of wrought-iron A, fig.2, 14 inch broad, inch thick, and 2 feet long, forms the foundation-shaft. Το this is welded, about midway in length, another bar B, of sufficient strength, which carries the curved branches Cand D, shown in fig. 1. This frame is made so as to be put into the groove in the gantry (which should be about 2 inches wide), and is supported by two centres, E and F, one in the end of the latheframe, and the other fitted into the gantry groove so as to slide in it, and to be fixed by a screw above it (T). The summits of the branches have square parts, so that a sliding piece (U) may fit either of them, which carries the roller or rubber for working the rosette figures. UNIVERSAL ROSETTE." The width between the ends of the branches is 9 inches. The slide-rest is fixed on a frame placed on and at right angles to the bar A, and has an oscillating motion of its own, to be used either with or without that of the main frame. For this purpose a piece of cast-iron, with two arms, figs. 1, 2, 3, G, is fitted so as to slide on the main bar betwixt H and I, and to be secured by two keys. At each end of the arms is a hole to receive the centres of the frame, carrying the slide-rest, figs. 1, 2, 3, K. Upon the top of this frame the rest is placed, and is made to traverse by a slide, having a set screw. In order to secure the frame K firmly, when its right-angled motion is not required, I have a standard of wrought-iron (L) fitting upon the end of the bar A, which is fixed in its place by a key through its ends, which embrace the bar, and fit into shallow grooves in it so as to keep the standard firm. A thin bar (S), having a groove, is screwed to the piece carrying the rest, and is secured by a screw working in the groove into the top of the standard. I also fix the spiral-spring M for regulating the cross-motion to the same part. The spring has five or six coils, and one end of it has a flat part with a square hole, so as to be slipped on to a pin in the restframe. The other end of the spring is about 4 inches long, and has a screwthread passing through a hole in the standard L, having a nut on each side of it, so that when altering the positions of the rest the spring may be regulated in conformity, so as either to draw or to push, as may be required. The spring for the principal frame is fitted on to the end of the main bar close to the standard (see figs. 1, 2, 3). N is a socket which fits tightly, and a pin goes through both. At O is a joint, and a thin bar Q works in it, passing upwards through the table to a level with the gantry, having notches on one edge, which fit upon the edge of a plate screwed to the table, and a wedge keeps it steady. The action of this spring is to pull either of the arms of the frame C and D (carrying the roller slide) up to the rosette, to give the figure. Having thus far described the frames, I will go to the contrivance, to which, from the infinite variety of figures it is capable of producing, I have given the name "Universal Rosette." Fig. 4 is a |