On Musical and Sensitive Flames
355 I am sorry to say that at the present time the deception is vast living body the throbbings of the universe announc� the I with smoke. This histori;Jal notice wouid be unjust without still practiced of engraving false names on their imitations accord of its varied parts. This rhythmic flow of nature conreferring to an observation made ten years ago in America by of American watches. But if they were to engrave them in stitutes most literally the " Music of the Spheres. " Not this ,
... Leconte. That physicist had noticed that certain this way: American Caliber or Style-then put their names if I but a less ethereal music , I have had the honor of being in-sustained sounds in an instrumental concert caused a very they wished , or leave them blank , I believe it would be more vited to bring before you this afternoon. susceptible movement of the ordinary gas flames in the room. honorable , both for the maker and the dealer; and although The 1I0-called musical or singing flames were discovered This observation is really the germ of the more wonderful some may make money by the operation , I do not envy them nearly a century ago by a native of this city , Dr. Higgins , effects afterwards independently discovered by the lecturer. their gains. who found that , when a flame of hydrogen was burning within Though Professor Leconte was the first to publish the fact , in In England this fraud was not carried to such an extent , a glass tube , the flame emitted a musical note. The experi-1838, it appears that , previous to this date , artisans had fre· yet it was and is still done in many instances , by putting the ment was repeated; and it was moreover shown that glass quently noticed the phenomenon as resulting from the shrill names of good makers on very inferior watches. In both tubes were not necessary , for similar sounds , though of differ. sounds of their work; and several musicians have informed countries the laws against this is very severe : yet the un-ent quality , were produced when metal or pasteboard tubes the lecturer that the same effect has been one they have com· principled find means to evade the law-and throughout the were employed. Neither was it necessary to use hydrogen , monly observed. world men are found who value money better than good rep· fo r a small flame of common coal gas gave a musical note Turning now from scientific history to experiment , the lec. utation. The Swiss are now , as the saying goes , "being paid when burning within a tube. turer showed various kinds and degress of sensitive flames. back in their own coin , " for many who first induced them to The cause of this phenomenon had been investigated by First , a "batswing" flame , which , under the ordinary gas do this wrong at'e now trying to injure their manufactures, many , but most successfully by an illustrious man who had pressure , moved slightly at the sound of a whistle , but thrust by giving them a bad name; and they will take time to reo lately passed from among us-a man who has left behind out long tongues of fire when the pressure was increased by gain what they have lost , but it can and I trust will be done. him a name as good as it was great , and who possessed a urging the gas from a holder. The increased pressure was My Swiss readers must forgive me if I am too severe. But mind as simple and child-like as it was sagacious and pro-always necessary to obtain the more sensitive flames , for a although myself and my descendants are now Americans , yet found-the late Professor Faraday. This sub ject had been reason that will be understood directly. A jet of gas , issuing Switzerland , my native land , with all thy faults I love thee one of Faraday's early flames. The cause was shown to be from a V-shaped orifi ce , was shown to be quite insensible to still , and if thou errest I must tell thee , for my idea is. that due to the fact that the gas, in issuing from the burner , did sound until the flame reached a hight of ten or twelve inches , to prosper in this world , and to have no fear of the next , one not burn silently. It rustled in passing through the orifice and then , at the sound of cBrtain high notes, the flame short must act on the square towards aE men , and be willing to of the burner , and in burning it made a continuous series of ened aRd spread out into a fan shape. Whistling to this be judged by our deeds. inaudible explosions. Thie was proved by sever. al experiflame in one key had no effect , while in another t4e effect was The reader , I think , must allow that although born in ments , for , by suitable means both these causes could be exvery marked. Playing an air upon a so-called bird-organ , Switzerland and educated in England , I speak plainly and im-alted so as to become sellsible. The resonance of the tube the flllme selected the high notes , and promptly shortened at partially , and I always intend to do So when I see a wroug placed over the flame renders audible all the sounds of a certheir recurrence. done , but I desire not to offend any one. If any feel them-tain pitch made by the gas. By a series of experiments it The probable cause of the sensitiveness of these flames was selves aggrieved, to them I say , we had far better appear was then proved that any noise , if made regularly and with then alluded to. The impact of air evidently had nothing to what we are than pretend to be what we are not. sufficient rapidity , was converted into a musical note. Thus do with the phenomenon. This was strikingly shown in the Watches whose cases open at the back by a spring are not rough and rude taps , and hard and harsh explosions could be following experiment; By tapping a membrane stretched so secure and free from dust as those with a proper snap. chased into perfect melody by mere rapidity of succession. over the mouth of a large tin funnel , a puff of air could be which can be made to shut close and open easily; springs are The condition of the flame when burning within the tube driven with such force from the narrow extremity that a can only necessary for wearers whose fingers are particularly soft , was shown by a moving mirror. It was seen that when the dIe was easily extinguished some twelve feet away. Direct· or to raise the covers of hunting watches. flame was silent , and the mirror moving , a band of light was ing this puff of air against the sensitive flame , it was seen Hunting watches have a cover to protect the glass , and it produced; but when the flame was sounding , this luminous that the flame moved violently , but was utterly unaffected will do so when sufficiently thick and convex , but very flat ribbon was broken up into a series of disjointed images of when the puff was driven either to the right or left. This hunters neither admit of the necessary shape nor thickness; flame. The eff ect of lengthening the tube in which the should also be the case if in former experiments it were the in many that are now made , particularly Swiss watches , the flame was burning was next shown , and a series of gas jets impact of the air , and not the sound , that produced the effect. glass is nearly as liable to be broken from pressure as it was burning within glass tubes of varying length gave a corres. But it was at once seen that when the lecturer whistled , at when unprotected, and the difficulty of procuring another is ponding series of musical notes of varying pitch. By placing the same time slowly turning round , the flame still continued muck greater. When flatness is necesE\ll ry , an open-faced the finger upon the top of these tubes the sound could be to shrink, and was almost as powerfully moved when the watch should be preferred , with a number of spare glasses , que nched , and thus a novel musical instrument could be back was turned to the flame. The effect , then , is solely pro which a very little practice will enable any wearer to put constructed. From glass tubes the lecturer passed on to show duced by the wave-like to and fro motion of the sonorous properly in their place. the effects of flames burning within extremely long tin pUlses. As first indicated by Professor Leconte , a gas flame , In giving advice with regard to choosing a watch , I have tubes. Within a tube six feet long , and about one and one. to be sensitive , has to be brought near its point of roaring; it said nothing but what every good watchmaker or importer of half inches in diameter , the flame of a large gas burner gave then stands , according to Dr. Tyndall , as it were on the brink Abstract of a Lecture delivered belore the DubliG Royal Society, by W. F. Barrett.) of which has been the discovery of the conditions of success turn this music?" ShoUld we not instantly condemn a speech for obtaining flames sensitive to the slightest sound. Some so characteristic of a sordid and sensuous mind? And when One of the earliest natural facts which arrest the attention month after the above observation , Professor Tyndall took up the student of nature is listening with admiration and even of a thoughtful mind is the stability of the wonderfUl unithe subject, and having largely added to its interest and imawe to the sweet, though silent , music sung to him by every verse in which we live. This permanency is, nevertheless , portance , offered an explanation of the phenomenon in a lecobject of his diligent study-by air and water , by flowers and the product of incessant change; for nothing is absolutely ture delivered at the Royal Institution , in January , 1867. At flowers-he is conscious that he bows before an oratorio as at rest. The secret of the stability of nature , its unresting this lecture the discovery was first published, and the name far above that of Handel as the works of the Creator are su repose , is found in the fact that the motion is regular-the given to" Sensitive Flames." Subsequently the lecturer had perior to the composition of the creature. change is periodic. Atoms , as well as planets. have their proposed a fuller explanation , and had discovered that not Still , however , the lecturer was enabled to show a practical period of revolution. Hence , sooner or later , in the physical only flames , but all gases could be rendered extremely sensiapplication of these sensitiv e flames. Attention was drawn world at any rate, phenomena repeat them�elves. Like a tive to sound, the track of the gas being marked by mixing it to the fact, that the flame sho):1;ened and lipread out laterally © 1868 SCIENTIFIC AMERICAN, INC. 356 under the influence of a whistle. Advantage was taken of this peculiarity to construct an instrument which may be turned to some practical use. The instrument consists of two sliding brass rods , bb' (see diagram) , attached at right angles; to the summit of one is a compound metallic ribbon , con8ist ing of thin layers of silver , gold , and platinum , welded together. This arrangement expands unequally by heat , by so doing it swerves aside , and is thus brought into contact with a platinum point projecting from the top of the second brass rod , which is fixed about half an inch from the free extremity of the compound metallic ribbon. Connected with the two brass rods is an elec tric battery , associated with which is an electric bell , placed in a far distant part of the room. The bell will immediately ring if the elec tric circle be complete , but at present there is a gap in the circuit between the me tallic rib bon and the plati num point. "I now ignite , " said the lecturer, "a sensi tive flame , which , in its ordinary sta te , burns at about two inches from the compound metal ribbon. I retreat some thirty feet from the flame , and whistle; the flame at once responds; it shrinks and spreads out sideways. By so doing it comes in contact with the metal ribbon; the latter instantly springs aside at the warm touch of the flame , strikes against the platinum point , com· pletes the electric circuit , and there you hear that distant bell answering me every time I whistle . " In the same way , at any hour of the night , the crying of a child in it9 cot would automatically announce itself in its parent's room. By a somewhat similar arrangement , using , however , a different burner, a burglar filing the iron-cased doors of a jeweller'S shop could be made to sound an alarm bell; and it is even possible , by making use of the propagation of sound through water , the reflection of that sound through a trumpet im mersed in the water, and its conduction to a sensitive flame , shut out by non-conductors of sound from the noises on board ship , that an arrangement might be constructed by which the approach of a vessel in a fog might be detected by ring ing a bell in the captain's cabin. It is not , however , my province to develop such inventions. With diffidence I throw out these suggestions , which may , I trust , by the practical I present above another diagram, wherein the lines of com parison have no contact with each other. The four lines ard' exactly equal in length, yet there is a great apparent differ� ence. I doubt whether it is possible for any person to group mere straight lines , or bars, in any other manner , to show such a speming disparity as appears in this. It is worth try' ing , merely for pastime , if nothing more.