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that of the common fountain lamp. Should the latter is exceedingly imperfect. This any of your readers be in possession of

efforts, have laid it aside as useless, it may be satisfactory to them to know, that with very little trouble and expense, their lamp may be rendered a very serviceable instrument for giving light, the alterations required being nothing but what any common tin smith is competent to under

The form of the lamp in my possession

Fig. 1.

Fig. 2.
...... N

..M
„N

M same in principle as Parker's Patent

ever since been as steady and uniform as Fountain Lamp, but that the action of arises not from any error in the prin

one of these lamps, and, after fruitless ciple, but from its being imperfectly carried out, by a faulty construction of the lamp, which prevents the end in view being obtained. Having one of these (Parker's) lamps, which I could never get to succeed, I had it altered with the view of rectifying the faults alluded to, and the result fully answered my expec take. tation; for the action of the lamp has

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is that of a hollow pillar, containing a of an inch of the top, in order to obviate cylindrical tin case, which constitutes the the risk of the oil flowing over by any lamp. Fig. 1 is a section of the tin case moving of the lamp. or lamp in its original state ; fig. 2, of To prepare the lamp for use. The the same in its altered state. An inspec

cap 2 being taken off, pour in at the cention will show in what respects they dif tre tube as much oil as will fill the case fer, and, assisted with a short explana 4; then fill the middle compartment at 2, tion, what alteration is required to render and screw on the cap: then, having filled the lamp manageable and certain in its

the upper compartment and screwed on action.

the cap 1, open the valve by turning the The upper compartment, correspond rack, and oil will descend into the centre ing with the reservoir of the common tube until it rises to the level of the air fountain lamp, is to have an opening (1) at hole ; at the same time, the compression top for filling it with oil, which is to be of the included air will be raising a corfitted with an air-tight screw cap; the responding column of oil to the burner. only communication it has with the ex To restore the lamp after it has been ternal air, is by an air hole (shown by a used.-Invert the case, when the oil in small circle) at bottom, communicating the lower compartment will flow into, and with the centre tube, which passes down fill the middle one, the surplus passing through the middle of the instrument; down the burner tube and flowing out; this communication is closed, while filling then return it to its right position, and in the oil, by a valve attached to the end removing the cap 2, pour in oil at the of a wire passing through a stuffing-box centre tube, until bubbles of air begin to and fixed to the rack, which raises the come up through the oil in the middle wick. The tube (2) communicating with compartment, and then screw on the cap the middle compartment, has also an air- again : next supply the upper comparttight screw cap, and is so made in the ment with oil as before.. patent lamps. A case, 3, encloses the I am, Sir, &c. lower part of the tube going up to the

N. N. L. burner, and a short tube communicating December, 1812. with the lower compartment, and rising about 1} inch higher : the only communication between this case and the middle compartment is by an air hole in ON INSTRUMENTS OF MUSIC, PLAYED BY its side (shown by a small circle) mid

FINGER AND BY MECHANICAL way between the bottom and top of the two tubes just mentioned. The centre Sir,- In a former communication on tube terminates near the bottom of an the subject of musical instruments, whose open box, or casc (4), which is soldered to sounds are produced on the principle of it, and has a semicircular notch or lip the free reed, I adverted to some others cut in its upper edge to cause the oil which have the great advantage of their to drop over in a more steady and gra sounds being varied in power and quality dual manner.

This case should be made by the pressure of the finger of the perof such capacity as to contain, without former; and as this affords a capability flowing over at the lip, as much oil as of expression but little inferior to that would fill the centre tube up to or above possessed by the violinist, combined with the air hole of the upper compartment;

the advantage of the parts being executed and there should be left sufficient space by one performer, I irust an examination at the bottom of the lower compartment of the construction of them, and the ad. to contain the oil dropping over at the vantages possessed by the different melip, as the action of the lamp becomes thods which have been employed to effect impaired when the oil rises above the the above purpose, may be at least bearlevel of the lip. Another point to be able to such of your readers as delight attended to, is to make M M, the distance in the "concord of sweet sounds." from the air hole of the upper compart

It may be remarked, that, in nearly ment to the lip of the case (4,) equal to all the musical instruments which have N N, the distance from the air hole of been designed to have their sounds swelled case 3, to the top of the wick tube, or by the pressure of the finger of the per. burner, or more usefully, to within ths former, the vibrations of the elastic body, VOL, XXXVII.

00

Τ Η Σ
FRICTION,

on which the pitch of their sounds de doubt had a horror of the monster's pends, has been either excited or con excessive competition,” equalling that tinued by the friction of some moving of Robert Owen himself. substance, acting in a similar manner to The best mechanical fiddle ever conthe bow of the violin ; and indeed the structed is that powerful and full-toned great desideratum appears to be to con instrument, the claviol, or keyed violin, trive a substitute for a bow, which shall of my respected friend, John Isaac Hawa be capable of eliciting tones comparable kins, Esq., the excellence of whose tone to those produced by that simple con is probably due to the construction of trivance in the hand of a Paganini. the wheels, or substitutes for bows, and From the perfect swell obtained by per a more scientific adjustment of the veloformers on wind instruments by more city of their motions to the rates of the forcible blowing, it would naturally be vibrations of the strings ; for it is of supposed that a perfect swell could be great practical importance, for the purobtained in the organ by having a com pose of ensuring an equal quality of tone mand over the pressure of air in the throughout the compass of such instru. wind-chest; but, unfortunately, this puts ments, that the motions of the bows, or the instrument out of tune, and we are whatever is substituted for bows, should compelled to bear with that very imper be well proportioned to the pitch of the fect substitute, a swell pedal, which merely sounds. In a compass of six octaves, peropens a box, but cannot affect the rela haps, the motion of the high treble bow tive power of any one sound produced should be five or six times as rapid as by the pipes within it. In the eolophon, that for the lower bass sounds. In the and other instruments constructed on the claviol the substitutes for bows are hoops free reed or valve principle, a very per perforated by a great number of holes, fect swell inay be obtained by increasing through which horse hair is passed, so the pressure of the wind, which does not that the interior surface of each hoop materially alter the pitch ; and by having becomes a polygon, whose angles are an extra bellows, and two or more rows very numerous. of keys, I am convinced very expressive It was a favourite theory with the effects may be attained. The earliest mathematicians, that a circle is only that instrument of continued sound with which impossible bull "an infinite number of I am acquainted, whose sounds depend straight lines, whose angles of intersecon friction, is the once common hurdy tion are infinitely small. Now, for every gurdy, or vielle ; and, however barbar.

practical purpose, the angles formed by ous its sounds may be deemed, they are the crossing within the hoop are infinitely an expressive type of a rather large class small; for, from their relative position of bad mechanical fiddles, which have and great number, combined with the been tried and found wanting during elasticity of the hair, the ear is unable the last half century. In this instrument to detect any inequality of tone. This a wooden (!!) wheel or cylinder is made to excellent contrivance, worthy its talented rub against the strings; and, between the author, was pirated by the French for dead harshness of the tone produced by an instrument termed the orchestrina, the "wooden" wheel, and the chattering and, like the ever-pointed pencil of the of the strings, produced by imperfect same individual, is less known to the stopping at what should be their aliquot public as the production of its inventor, parts, the noise is almost enough to pro than as associated with other names. duce a mortification of our auditory The claviol has many other advantages,

A monstrous hurdy-gurdy—it in particular that of standing remarkably had a fairer name given to it, but it was well in tune, which is effected by proone-was constructed, about ten ortwelve tecting the gut strings from atmospheric years since, for the Italian Opera, with humidity by a coating of varnish, and the modest'intention of superseding the preserving an almost perfectly uniform double basses, &c.; but from the diffi force of tension, by attaching one end of culty of stopping, which was attempted each string to a very long helical spring, by an action similar to that of the harp, made of hardened and tempered steel and perhaps its defects of tone, it was wire. By these arrangements the pitch laid aside, to the great relief of Messrs. is prevented from undergoing any consiLinley, Dragonetti, and Co., who no derable variation with the extreme vari

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ations of atmospheric temperature, and fined to the ædephon, for it exists to a the intonation is preserved almost as greater degree in that delightful instruperfectly as if the sounds were produced ment, the harmonicon of Dr. Franklin, by as many tuning forks.

in which the glass bells are all fixed on The mention of tuning forks has re one spindle or axis; and, consequently, minded me that a musical instrument has the larger ones, which produce the bass been constructed, which consists of a sounds, perform the same number of reseries of such forks made to vibrate by a volutions per minute as the small bells rosined silk band brought in contact with which utter the highest treble, though the prongs by means of a lever, at one their peripheries being so much larger, end of which is a small pulley, the other the motion of the surfaces is much being connected with the finger key. I quicker. This evil might be avoided by think Mr. Goldsworthy Gurney, of steam putting each octave of bells on to a sepalocomotive notoriety, constructed an in rate axis, and if the axes were made strument of this kind, as well as his piano, tubular, and one allowed to revolve within which heavy steel springs are substi in the other, any required speed might tuted for strings, neither of which are be communicated to each, and the quality much more novel than the arrangements of the tone be rendered equal throughout of his steam carriage, which resembles the compass. The harmonicon is subject Trevethick's, for I have seen a piano-forte to the very disagreeable accident of the of this kind thirty years old. Both in glass bells breaking in use, by which the struments labour under the great defect fingers of the performer are liable to be of requiring much power to put the severely cut, if applied directly to the heavy springs into a state of vibration, glass bells. Those made to play with which causes the bowing in one, and the keys are not so dangerous, but the tone blow of the other to be too much heard, is not so good. Perhaps some of your a defect which does not exist when the musical readers can inform me if a vibrating parts are not heavier than the harmonicon has yet been constructed with steel or gut strings of a piano or violin. metal bells; they would possess the ad

Nearly allied to the instrument con vantage of not being liable to fracture, sisting of tuning-forks is the terpodian, and the compass might be carried lower and what is nearly the same the ædephon; in the bass with more facility ; they but instead of the vibrating springs being would also be very easy to tune, which in the form of forks, they are cylindrical glasses certainly are not, as any one who rods of metal, from which depend thin has made the attempt can testify. The pieces of brass, on the fronts of which are tone and power of expression on this inaffixed pieces of felt. The action brings strument are so delightful that it deserves the thin piece of brass, or rather its some labour should be bestowed on the covering of felt, against a revolving cylin attempt to diminish its defects. der of metal, or more properly a number When describing the claviol I ought of cylinders on one axis, whose surfaces to have mentioned what should perhaps are coated with rosin. The bowing ac be termed a humble imitation of that intion of the cylinders is communicated by strument, which was exhibited to the the depending pieces of brass to rods musical public under the title of euphoabove, causing them to vibrate. The non. In this instrument the strings are tones thus produced are most delightful of steel wire, excepting the bass, and in the middle part of the compass, and they are put into vibration by an endless the swell produced by the pressure of the band, acting as a bow, one band to each finger, is perhaps superior to that of any string. It is less expensive in construcother keyed instrument; but it is difficult tion than the claviol, but its tone is far

to keep in order, and the quality of tone inferior in power and quality, and from • varies much at the extremities of the the great number of bows or bands is

compass; but this I attribute to a strange more difficult to keep in order; besides, it error of the maker, who has put the has no contrivance for insuring a nearly largest cylinder to act on the bass rods, equal straining force on its strings, and and the smallest to the treble ; and all the consequently does not stand in tune better cylinders being on the axis, the rates of than an ordinary piano, which it much motion of their surfaces are just contrary resembles in its construction, excepting to what they should be : an evil not cons the action. Instruments of this kind, I

believe, are not very modern. I saw one these points is not absolutely fixed, it ten years ago, perhaps thirty or forty being the end of a very long helical years old, which was of German manu spring, which might be stretched perhaps facture, but they underwent some im the twentieth part of an inch without provements by Mr. Pinnock, and also I greatly increasing the straining force. believe by Mr. Hawkins. In the old one, This, I believe, is the cause of the pitch before mentioned, the bows or endless of that instrument not rising when the bands all moved with the same velocity, sound is swelled to any very appreciable but I believe this great error was cor extent. rected in some of the more modern in I feel this very long article ought to struments. The same contrivance of be concluded, but cannot find the heart bands or bows has been applied in Ame to do so without adverting to the sos. rica to continue the sounds of the piano tinente pianoforte of the ingenious Mr. forte, See article Piano, Herbert's Mott. This instrument, which comCyclopedia.

bines the rapidity of the most brilliant The late Mr. Walker, whose Lectures pianoforte execution, with the power of on Astronomy are amongst the memo sustaining and swelling the sounds and rabilia of our immediate progenitors for varying their quality at the pleasure of many years, used to perform the music the performer, must, I think, stand A 1 of the spheres” on an instrument he in the scale of excellence of instruments termed the celestina, and much specula with keys. Its power of sustaining its tion existed as to how its delicate tone sound is due to an interesting fact in was produced; but as all human secrets physical science, viz., that if an exciting are in time discovered, it was found to be cause of vibration (as for instance the nothing but that much underrated instru. action of a bow) be applied to an elastic ment the harpsichord; and as the action body, the motion so imparted will be is of easy construction, and the effects communicated to another elastic body in of the instrument very pleasing, I may, contact with the first. The talented inMr. Editor, should you think it would be ventor applied this principle by making acceptable, at some future period de this substitute for a bow act not immescribe it more fully for the benefit of such diately on the strings of the piano, but on of your readers who, being both mecha a series of pieces of silk or hair attached nical and musical, may desire to con. to them, and by this happy thought obstruct it for themselves; but the length viated the evils which would ensue from of this communication already warns me want of elasticity in the cylinder, thereby that I must say no more at present than greatly improving the tone and producing that it consists of an endless band of silk, à touch which enables the fingers of the rosined, which is made to rub against the performer to do that his mind willeth to strings by being brought, while in mo do; but I need not go into further detion, between the two strings, which are tails of the construction of this instruturned in unison by small pullies which ment, as we may congratulate ourselves are affixed to the ends of levers connected on living in an age when it is procurable with the finger-key. It is obvious that for love or lucre, which is not the case in the celestina the friction of the end with the claviol, celestina, ædophon, and less band may be used either originally some others, which, like the tones of to excite the vibration of the strings, or Paganini's fiddle and Malibran's voice, to continue their vibrations after being are heard no more in the land. struck by the plectra, and of course the

Yours most respectfully, sound is very perfectly swelled by in

ALFRED SAVAGE. creasing the

pressure of the finger on the 16, Garlick Hill. key and moving the pedal quicker, having the general defect of raising the pitch

COLD-BLAST ANTHRACITE IRON. thereby. This evil is very perceptible in the swell of all instruments with metal

The Ystalyfera Iron Company beg to hand strings which are sounded by friction.

to the Editor of the Mechanics' Magazine a The pitch of a gut string does not rise so

copy of Mr. Mushet's elaborate trials on much, but still it is sensible when the their cold-blast anthracite iron, which they two points to which the strings are affixed hope he will think of sufficient importance are immovable. In the claviol one of and interest to deserve insertion in his next

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