Page:The New International Encyclopædia 1st ed. v. 14.djvu/198

* MUSHROOM. 162 MUSIC. oughly liigested. Kcccnt exiM'riments show that 25 to 5!) per cent, is indigestible. See Plates of Edible a.d Poisonous Fi;x(ji. Biui.iocRAHiiy. Consult: Mollvaine, Oiw Thou- sand Atiicrican Funyi (Indianapolis, 1900); At- kinson. •Studies of Aiiicricun Fuiiiji, Edible and Poisonous Mushrooms (Ithaca, N". Y., 1900); per second. Heat vibrations begin at 134 tril- lions per second; light vibrations, visible to the eye, at 483 trillions. The gamut of the rainbow lias its velocity measurements. Chemical vibra- tions, "shown only by certain reactions in pre- pared photographic plates," are beyond our sense perceptions. Sonorous vibrations, then, are really J?adnian. Treatise on the Eseulent Funguses of the slowest of all. Dr. William Ramsay asserta Enyhind (London. 1803); Cooke. Edible atid Poisonous Mushrooms (London, 1894) : Dallas and Burgin, .4»io»;/ the Mushrooms (Philadel- phia, 1900) ; Falconer, How to Grow Mushrooms (New York, 1892) ; id.. United States Dejiart- nunt of Agrieutlure, Farmers' Bulletin oJ (Washington. 1897) ; Farlow, "Some Edible and Poisonous Fungi," United .States Department Agrieullural Yearbook (Washington, 1894); Gibson. Our Edible Toadstools and ^iushrooms (New York. 1895) ; Palmer, About Mushrooms (Boston. 1894) ; Peck, Mushrooms and Their Uses (Cambridge, Jlass., 1897); Smith. Mush- rooms and Toadstools (Ixmdon, 1879); Robin- son, On Mushroom Culture ( ib., 1870); Ilussey, Illnslrations of liritish Miieoloyij (ib.. 1855); Taylor, student's Handbook of Mushrooms of America (Washington, 1897). MUSHROOM GNAT. The name given bv in his Essay o)i Smell, that tlie sense of smell ' is excited by vibrations of a lower period than light and heat. Sounds of a musical character rarely extend beyond a minimum of 10 and a maxinmni of 4138 vibrations, respectively the | rates of vibration of the lowest tone of an organ i with a pipe of thirty-two feet and the top note I of a piccolo. The production of sound, its trans-, mission, and its aural perception may all be : demonstrated with a long piece of stretched string. In its position of equilibrium it repre- sents a straight line; pluck it and its elasticity will cause it to return. This is a simple vibra- i tion. But the string also goes in the opposite direction, and this is a double vibration. Like a pendulum, the vibrations of the string are iso- • ehronous, each occupyijig exactly the same length ' of time. By shortening the string or increasing } its tension we get vibrations of various velocities, ' and the ear perceives various pitches from 16 mushr.Kiin Lirowcrs to any of the fungus-gnats vil.rations to the second up to 4224 vibrations of the family .lycct(.[)hilid;r. (See Gnat.) These Increase the tension bevond this point, shrillness are small, niosquito-like creatures with feathered point, shrillness i results, below IG a dull unmusical whirring. The '[ same results acoustically may be produced with. pipes of varying lengths. The vibrations are, as in the ease with strings, isochronous; they ) vary in rapidity according to the length of the ^ pipe: subdivide them and harmonics are pro- ^i. duced. Nodes and vibrating segments are the (| crude material of music; pitch, force, or loudness, ; and timbre or quality of tone. All these quali- i MUSIC (OF., Fr. jiih-siV/hc. from Lat. musica, ties depend upon the rapidity of the vibrations, f from Uk. fu)V(TiKi/i, «iohai7,(", music, from /wvffiKit, It is demonstrated : that the number of vibrations ll nmusikos. relating to the ]Muses. from MoCo-o, of strings is inversely proportional to their ^' length; that the number of vibrations of strings .'' antenna and frequent, as a rule, vegetalile mat- ter or fungi, upon which their larva- feeil. The larviE are slender, white, wormlike creatures, with a distinct black head. The larva of one species of the genus Sciara is especially injurious to mushrooms, which it eats into and ruins. In mushriKjni cellars, fumigation with tobacco or pyrethruiii will kill the llies. iMousa, !Muse). Ohigins. .Music is a mode of motion. It is a modification by art of aerial vibrations, whose inii>act upon the auditory nerve makes mental varying images. Sound, the raw material from which music is fashioned, is pro- duced l)y motion. Matter is the stimulus; sensation is the result. "The kind of motion, however, that goes to produce sound is not that of matter precisely, but rather of the molecules or ultimate particles of which iiiiitter is composed. When tlie state of equilibrium of an elastic body is disturbed by a shock or by friction, it tends to regain its condition of equilibrium, but does so only after a greater or less number of vibrations, or oscillat- ing movements, of the molecules of which the mass of the body is composed." Thus .T. A. Zahm. a profouiKl investigator in acoustics and a follower of the great llelinlioltz. whose mas- terly tonal researches are set forth In his Die Lchre ron drn Tonempfindunyen. The nature of sound. Lord Bacon observes, "in general hath been superlicially observed. It is one of the !» is in inverse ratio to their diameter; that ex- i Jierimenting with two wires at tension, but of *i dilTcrlng ilensity, we get the rule that the number fj of vibrations of a string is inversely proi)ortional | to the square root of their density; finally, as? Ilelmholtz shows by varying the stretching weight, that the number of vibrations of strings is directly proportional to the square root of their stretching weights. Thus the longer, thicker, heavier a string is. the slower are its vibrations; the deeper is its tone. The shorter, finer, lighter, tenser it is. the more rapid are its vibrations; the higher is its tone. Now the sound ]iroduccd by a string vibrating its entire length is its funda- mental or natural tone. It can produce many other sounds at the same time, subdividing tliera as it vibrates; there are the overtones cjr har- monics, partial and concomitant sounds. The series of harmonics theoretically may be divided inlinitely, but iiir musical purposes they are numbered in accordance with the number of vibrating seiiments or loops. The nodes exceed t} siilitilest pieces of Nature." The nineteenth cen- by one in number the loops — taking the ends of tury has endeavored to wipe away Bacon's re- the tense string as nodes. The fundamental vi- proach. for the studies and experimentings of brating with one loop is the first harmonic of the such men as Helmholtz, Rudolf Ki'mig, and tone, and the harmonics on the numerical order others have lifted into light the darkest |)roblems are constantly nearer and nearer together, the of neouslies. The latest researches teach us that successive intervals being an octave, fifth, fourth, sound vibrations — vibrations audible to the ear — third, second. We arc at the very beginnings of have a rapidity which ranges from 16 to 3ti,.500 the .scale. The clay is ready for the musical