Indeed, the sound-bow of this bell is fuller outside than the Paris bell, because it is thicker; so much so, that a straight edge laid externally against the top of the bell and the sound-bow would be thrown out beyond the lip; whereas generally such a straight line would touch the lip, and just clear the sound-bow. I have found one other remarkable exception to this general rule of construction, and a remarkable coincidence with the external shape, and the proportions of height, breadth, and thickness of our bell, and that is no other than the great bell of Moscow, of which an exact section is given in Lyall's Russia, with various different versions of its weight. The inside shape, however, is not the same, and I am satisfied not so good, the curve being discontinuous, and presenting an angle just below where the clapper strikes, as in the Paris bell. That bell seems to have had a very short life, a large piece having been broken out in a fire the year after it was cast. Sir Roderick Murchison tells me that the sound of the Russian bells is remarkably sweet.

I cannot find that the exact height of a bell makes much difference. The foreign bells, except the Russian ones, it seems, are generally higher than ours, being nearly ths of their diameter high, whether you measure it vertically inside, or obliquely outside from the lip to the top corner, as the two measures are generally much alike on account of the curvature of the top or crown. Ours run from 3rds to ths of the diameter, though there are some higher; and on the whole my impression is against the high ones. The vertical height inside of all these bells at Westminster is 14ths of the diameter. Lower than that, the bell does not look well; I never saw an ugly bell that was a good one; and it is clear, from all our experiments, that the upper or nearly cylindrical part is of considerable importance, and though its vibrations are hardly sensible, it cannot even be reduced in thickness without injury to the sound, of which we had a curious proof. A bell of the usual proportions, in which the thickness of the upper or thin part is one-third of the sound-bow or thickest part, sounds a third or a fourth above the proper note when it is struck in the waist, and the sound there is generally harsh and unmusical besides. It occurred to both my colleague, the Rev. W. Taylor, and myself, that it would be better to make the waist thinner, so as to give the same note as the sound-bow. After two or three trials we succeeded in doing this very nearly, and without reducing the weight below th instead of 3rd of the sound-bow. The bell sounded very freely with a light blow, and kept the sound a long time, and a blow on the waist gave a much better sound than usual. But for all that, when we tried it at a distance with another bell of the same size and same thickness of sound-bow, but a thicker waist, the thin one was manifestly the worst, and had a peculiar unsteadiness of tone, and sounded more of what they call the harmonics along with the fundamental note, instead of less, as we expected.

But still we have to ascertain what should be the thickness of the sound-bow itself (which is often called for shortness the thickness of the bell). The large bells of a peal are sometimes made as thin as th of the diameter, and by one of the modern bellfounders even thinner, and the small ones as thick as th of the diameter. It is clear that the most effective proportion is from to 1. In casting peals of bells it is necessary to take rather a wider range, in order to prevent the treble being so small and weak as to be overpowered by the tenor; though here I am convinced that the modern bellfounders run into the opposite error, and always make their large bells too thin. I know several peals in London in which the large bells are hardly heard when they are all rung, and are besides very inferior in quality to the others. Again, if you make the small bells too thick, for the purpose of getting a larger bell to sound the proper note, you approach the state in which the bell is a lump of metal too thick to have any musical vibration. This is a much less common fault than the other, because the nearly universal demand for as deep notes as can be got for the money is a strong temptation to make the thickest bells, i.e. the small ones, only just thick enough, and the large ones much too thin.

The thickness of the Westminster bell was designed to be ths of the diameter, or 9 inches, which would have made it 14 tons, the weight which was prescribed for it twelve or thirteen years ago, long before I had anything to do with the bells or the clock. By some mistake in setting out the pattern, or making the mould, which the founders have never been able to account for, the bell was made 9 in. thick, which is very nearlyth of the diameter, 9 ft. 54 in., and which increased the weight to 16 tons, within 174 lbs., and raised the note from E flat to E. For

tunately the same ratio of increase was made throughout, and the waist is 33 in., or one-third of the sound-bow, as it ought to be; and therefore the only effect of the mistake is, that the bell is heavier and more powerful; for it being cast the first, the alteration of the note did not signify, as the four quarter-bells can as easily be made to accord with E natural as with E flat. And as they will be rather smaller in consequence, the aggregate weight of the whole five will be about 24 tons, as I originally estimated. I have only to add, with reference to this part of the subject, that the width of the bell at the top inside is half the width at the mouth, as it generally is; though in some bells-for instance, the great clock bell at Exeter-it is the outside diameter that is made half the diameter at the mouth. It is of no use to state here the precise geometrical rules by which the pattern of a bell, of what we now call the Westminster pattern, is drawn, as they are purely empirical. I mean, that having got a bell, by trial, which we all agreed was better than any other, I made out some sufficiently simple rules for drawing the figure of its section by means of a few circles, whose radii are all some definite numbers of 24th parts of the diameter of the bell: but there is no kind of à priori reason, that I know of, why a bell whose section or sweep is made of those particular curves, should be better than any other; and therefore I call the rules for tracing the curve merely empirical; and as they would be of no use to any one but bellfounders, who know them already, or easily may, if they like, I shall say no more on this part of the subject.

As I have been asked many questions about the mode of calculating the size of a bell, so as to produce a particular note, and the answer is very simple, I may as well give it, though it may be found already, with other information on this subject, in the only English book I know of which contains such information-I mean the second edition of my Lectures on Church Building, to which a chapter on bells is added. If you make eight bells, of any shape and material, provided they are all of the same, and their sections exactly similar figures (in the mathematical sense of the word), they will sound the eight notes of the diatonic scale, if all their dimensions are in these proportions-60, 53, 48, 45, 40, 36, 32, 30; which are merely convenient figures for representing, with only one fraction, the inverse proportions of the times of vibration belonging to the eight notes of the scale. And so, if you want to make a bell, a fifth above a given one-for instance, the B bell to our E-it must be rds of the size in every dimension, unless you mean to vary the proportion of thickness to diameter; for the same rule then no longer holds, as a thinner bell will give the same note with a less diameter. The reason is, that, according to the general law of vibrating plates or springs, the time of thickness vibration of similar bells varies as When the bells are also com(diameter)2°

pletely similar solids, the thickness itself varies as the diameter, and then the time of vibration may be said simply to vary inversely as the diameter. But for a recent letter in the Times from a Doctor of Music, who seems to have taken this bell under his special protection, it would have seemed superfluous to add that the size of the " column of air contained within a bell" has no more to do with its note, than the quantity of air in an American clock has to do with the note of the wire on which it strikes. You may have half-a-dozen bells of different notes, because of different thicknesses, all enclosing exactly the same body of air. I certainly agree with the opinion published by some of the bellfounders on a former occasion, that musicians are by no means necessarily the best judges of bells, except as to the single point of their being in tune with each other.

The weights of bells of similar figures of course vary as the cubes of their diameters, and may be nearly enough represented by these numbers-216, 152, 110, 91, 64, 46, 33, 27. But as we are now only concerned with the making of a single bell, I shall say no more on this point, beyond desiring you to remember, that the exact tune of a set of bells, as they come out of the moulds, is quite a secondary consideration to their tone or quality of sound, because the notes can be altered, a little either way by cutting, but the quality of the tone will remain the same for ever; except that it gets louder for the first two or three years that the bell is used, probably from the particles arranging themselves more completely in a crystalline order under the hammering, as is well known to take place even in wrought iron.

The remainder of Mr. Denison's paper relates to the composition of bell-metal, and by a table of analyses, shows that the Westminster

Bell contains less tin and antimony together, and more copper, than the old bells of York Minster; and a great deal less tin in proportion to the copper than the famous bell of Rouen, which was broken up and melted into a cannon in the first French Revolution. The mode of casting the bell, and hanging it, follow. For the entire paper see the Reports of the Royal Institution Weekly Meetings-March 6, 1857.

We have only here to add, that the Great Bell having been conveyed from the foundry to Westminster, was cracked in the sounding before it was attempted to be raised, and has now to be re-cast.

CLIFFORD'S NEW METHOD OF LOWERING SHIPS' BOATS.

By this mechanically novel but simple invention,*—remedying the evils of the old system, productive of such melancholy loss of life at sea-a boat, when laden with a full crew, is, by the single act of one of the crew in the boat paying off a handline, at one and the same time unlashed, lowered evenly without the possibility of canting in descent, and entirely disengaged from the ship, whether at anchor or going at full speed. After having been subjected to most severe trials during the last two years by the Admiralty, the Emigration Commissioners, and the East India Company, this Boat has been adopted throughout their different services; and has been the means of saving the lives of men who have fallen overboard (in nearly every case when the ship was in full sail) from H.M.S. Shannon (Captain Peel, commander); from the emigrant ships Commodore Perry, Blundell, Black Eagle, Washington Irving, and Ebba Brahe; and from the Transatlantic, belonging to Messrs. Thompson, of Aberdeen. In several of these instances, the officers have officially reported that but for the boats being so fitted they would not have risked the lives of the crews in attempting to lower them, from the heavy sea running at the time. The example thus set by the Admiralty and the other public bodies above named, in providing for the crews and passengers of their ships so necessary a means of security in case of accident, will do incalculable good, and must lead not only to the laws now existing (though unhappily entirely disregarded) being enforced, but more stringent ones being passed for the better protection in future of life at sea.

PRINTING BY WATER POWER.

THE Montrose Standard is now printed by water power. The engine consists of two oscillating cylinders with pistons acting on the shaft of a driving pulley, the pistons being moved by water, as those of a locomotive or other steam-engine are by steam. It differs from the steam-engine chiefly in the absence of sliding valves, which are inappropriate to the employment of water in place of steam. The means through which these are dispensed with are in the highest degree simple and ingenious.

* Described in the Year-Book of Facts, 1856, p. 47.

Natural Philosophy.

THE ROYAL SOCIETY.

THE first anniversary meeting of the Royal Society, in their new rooms at Burlington House, Piccadilly, was held on Nov. 30, the Lord Wrottesley, President, in the chair. After the Report from the auditors of the income and expenditure for the past year, his lordship delivered his annual address, in which he advocated the claims of science to the recognition of all who are interested in the moral and physical progress of the nation. In reviewing the advance made in the department of terrestrial magnetism, he instanced the patient observations of Schwabe, of Berne, as an illustration of the valuable aid which one branch of science may undesignedly lend to another. For thirty years the obscure Swiss astronomer had daily noted down the appearance of spots on the solar disc, little thinking that his demonstration of a decennial period for the complete revolution of those remarkable phenomena would be made just in time to enable General Sabine to demonstrate in his turn the coincidence of that decennial period with that in which the phenomena of terrestrial magnetism-their maxima and minima-pass through a complete series. Modern science has no parallel to Schwabe's persevering labours.

The Government having promised to dispatch a vessel to explore the Zambesi, Lord Wrottesley expressed a hope that the request made to the First Lord of the Treasury, by a deputation of members of the British Association and Fellows of the Royal Society, for a small party to be sent out to take a three years' series of magnetic observations near the mouth of Mackenzie River, in Arctic America, would also be granted. These observations are of especial interest to physical science, as in the latitude of the abovenamed river will, it is thought, be found the neutral point between the magnetic disturbances, or storms," which manifest themselves at Point Barrow and Toronto simultaneously, but in opposite directions.

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The Foreign Secretary, Professor W. H. Miller, received the Copley Medal for Professor Michel-Eugène Chevreul, to whom it had been awarded by the Council of the Society, as a testimony on their part of his long-continued chemical investigations. The true nature of saponification was not understood until he, many years ago, elucidated it in a memoir which remains among the master works of chemistry. It opened the way for those important branches of industry which now send light all over the kingdom, in the form of stearine and composite candles. To Chevreul we owe the discovery that coarse and low-priced oils could be made to yield hard fats, eminently useful in commerce and domestic life. He has also greatly improved the art of dyeing, and his late work On the Law of the Contrast of Colours, has, in the original and by translations, made his name known wherever the fine arts are cultivated.

Dr. Edward Frankland, the recently appointed lecturer or che

mistry to St. Bartholomew's Hospital, was selected as the recipient of one of the two Royal Medals placed every year by the Crown at the disposal of the Society, for-to quote the words of the award -"The Isolation of the Organic Radicals of the Alcohols, and for his Researches on the Metallic Derivatives of Alcohol." The other Royal Medal was given to Dr. John Lindley, for his numerous researches and works on all branches of Scientific Botany, and especially for his Vegetable Kingdom and his Genera and Species of Orchidea.

SCIENCE AND THE GOVERNMENT.

AT the late Meeting of the British Association, in Dublin, the President, in his inaugural address, stated: An important question has been, for some years, under the consideration of the British Association, and that of the Royal Society-the question, namely, whether any measures could be adopted by the Government or Parliament that would improve the position of Science or its cultivators in this country. The Parliamentary Committee of the Association have taken much trouble in the attempt to arrive at a solution of this large and complex question. They consulted, in the first instance, several of the most eminent scientific men of this country; and in their first Report, presented to the meeting of the Association at Glasgow, they have analysed the replies obtained, and have recommended certain general measures founded thereon. The most important of these are the provision, at the cost of the nation, of a central building in London, in which the principal scientific societies of the metropolis may be located together, and the formation of a Scientific Board, to have the control and expenditure of the public funds allotted to the advancement of science. This Report was under the consideration of the Committee of Recommendations at the last two meetings of the Association, and the opinions of the members of the General Committee have been since invited in reference to its suggestions. The Council of the Royal Society have likewise deliberated on the same question, and have passed certain resolutions on the subject, which accord in substance with the conclusions of the Parliamentary Committee. A copy of these resolutions was forwarded by Lord Wrottesley, as President of the Society, to Lord Palmerston, and motions have been made in both Houses of Parliament for the production of the correspondence. The first of the objects above referred to, namely, the juxtaposition of the scientific societies of London in one locality, has been since accomplished by the grant of Burlington House for the use of the Royal, Linnean, and Chemical Societies.

THE BAKERIAN LECTURE.

THE Bakerian Lecture for 1857, at the Royal Society, delivered by Professor Faraday, is "On the Relations of Gold and Silver and other Metals to Light."

The lecturer commenced by expressing a hope that the undulatory theory of light, when more fully and perfectly developed, may aid in

H