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acqv Adult angle annuity appears applied arpu Axiom axis Cambridge CAMBRIDGE PHILOSOPHICAL SOCIETY capital chronometers clock condensations conic section considered constant curve density determined diameter diaphragm diminished direction disc distance disturbance dºp effect equal equation equi-convex eye-piece Female fluid force friction function GEORGE BIDDELL AIRY give given instant Hence increase integral interval length lens lenses longitude Male manner motion nearly object-glass observations obtained orifice paper plane particles pendulum pipe pitch plane plano-convex plumage portion position pressure principal vertex probability produce profits propagation quantity rarefaction ratio reed rent satellites shew shewn Society soil supposed supposition surface Table of mortality theorem tion Titmouse TRINITY COLLEGE tube varies velocity velocity of propagation vibration vowel wave
الصفحة 244 - Euler, if a single pulsation be excited at the bottom of a tube closed at one end, it will travel to the mouth of this tube with the velocity of sound. Here an echo of the pulsation will be formed which will run back again, be reflected from the bottom of the tube, and again present itself at the mouth where a new echo will be produced, and so on in succession till the motion is destroyed by friction and imperfect reflection — The effect therefore will be a propagation from the mouth of the tube...
الصفحة 233 - ... instruments, what forms of cavities or other conditions are essential to the production of these sounds, after which, by comparing these with the various positions of the human organs, it might be possible, not only to deduce the explanation and reason of their various positions, but to separate those parts and motions which are destined for the performance of their other functions, from those which are immediately peculiar to speech (if such...
الصفحة 116 - ... in which the bob is conceived to be a mere material particle, and the suspending rod is assumed to be devoid of mass, and the motion is assumed to be confined to some one vertical plane passing through the point of support, and all retarding influences, such as the resistance of the air and the friction at the point of support, are neglected. The "period of oscillation...
الصفحة 234 - ... parts and motions which are destined for the performance of their other functions, from those which are immediately peculiar to speech (if such exist) . " In repeating experiments of this kind, it must also be kept in mind, that the difference between the vowels, depends entirely upon contrast/23) and that they are therefore best distinguished by quick transitions from one to the other, and by not dwelling for any length of time upon any one of them. A simple trial will convince any person, that...
الصفحة 244 - ... the pulsation will be formed which will run back again, be reflected from the bottom of the tube, and again present itself at the mouth where a new echo will be produced, and so on in succession till the motion is destroyed by friction and imperfect reflection — The effect therefore will be a propagation from the mouth of the tube of a succession of equidistant pulsations alternately condensed and rarefied, at intervals corresponding to the time required for the pulse to travel down the tube...
الصفحة 239 - Let the line abed represent the length of the pipe measured from a, and take ab, be, cd, &c., respectively equal to the length of the stopped pipe in unison with the reed employed, that is, equal to half the length of the sonorous wave of the reed. " Now if the pipe be drawn out gradually, the tone of the reed, retaining its pitch, first puts on in succession the vowel qualities...
الصفحة 233 - ... than as a branch of acoustics." Soon after he goes on: " Kempelen's mistake, like that of every other writer on this subject, appears to lie in the tacit assumption, that every illustration [of vowel-sound] is to be sought for in the form and action of the organs of speech themselves, which, however paradoxical the assertion may appear, can never, I contend, lead to any accurate knowledge of the subject The vowels are mere affections of sound, which are not at all beyond the reach of...
الصفحة 194 - ... inasmuch as it will make it inevitably necessary to separate the moral axioms and assumptions on which the theories rest, from all other matter which may tend to obscure or confound them. It will also separate entirely the two parts of the subject which it is of immense importance to keep separate; — the business of proving these assumptions, and that of deducing their conclusions.
الصفحة 240 - ... as represented in the diagram, then in direct order again, and so on in cycles, each cycle being merely the repetition of bd, but the vowels becoming less distinct in each successive cycle. The distance of any given vowel from its respective centre points a, c, &c. being always the same in all. " When the pitch of the reed is high, some of the vowels become impossible. For instance, let the wave of the reed =ac (No. 3), where %ac is less than the length producing U. * "I use these letters throughout...
الصفحة 194 - Whewell then proceeded to consider an imaginary non-mathematical mechanics discerning therein three dangers all of which had in reality been overcome: They might have assumed their principles wrongly; they might have reasoned falsely from them in consequence of the complexity of the problem; or they might have neglected the disturbing causes which interfere with the effect of the principal forces. But the making mechanics into a Mathematical science supplied a remedy for all these defects. It made...