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Oscillation

Oscillation
Oscillation
Oscillation

"Oscillation is a rhythmically recurring translatory movement." [Keely]

OSCILLATION. - The swing of a pendulum, and its return. [Scientific Basis and Build of Music, page 25]

Not the same as vibration. [see Vibration]

Ramsay
"In the laws of quantities and motions there are three primary ratios from which the musical system of vibrations is developed. Pendulums, from the slowness and continuance of their motions, are well adapted to give an ocular demonstration of the relative motions of each of these three primary ratios when compared and combined with the unity and with each other. The numbers 2 and 4 express the first condition in the first ratio; as, in falling bodies, when the times are 2 the distances are 4. In the case of two pendulums, when the length of the one is one fourth part of the other the motions are 1:2; and when two is counted for the upper one, the oscillations of these two pendulums will meet at one. The numbers 3 and 9 express the first condition of the second ratio; as, in falling bodies, when the times are 3 the distances are 9. In the case of two pendulums, when the length of the one is the ninth part of the other, the motions are 1:3; and when three is counted for the upper one, the oscillations of these two pendulums will meet at one. The numbers 5 and 25 express the first condition in the third ratio; as, in falling bodies, when the times are 5 the distances are 25. In the case of two pendulums, when the length of the one is twenty-fifth part of the other, the motions are 1:5; and when five is counted for the upper one, the v of these two pendulums will meet at one. In the system of motions in pendulums, the three primary ratios indicated in the foregoing paragraph, namely, 2:4, 3:9, and 5:25, are compared and combined with three different units. In their comparison, 1 is the unit of quantities, that is lengths, and 1 is the unit of motions. The numbers 1/4, 1/9, and 1/25, when taken together with 1 as unity, express the first comparison and combination of quantities; and the numbers 2, 3, and 5, taken together with 1 as unity, express the first comparison and combination of motions." [Scientific Basis and Build of Music, page 15]

"The numbers which express the motions of these twenty-five quantities have among themselves nineteen different ratios, or rates of meeting; and when these ratios are represented by the oscillations of twenty-five pendulums, at the number of 64 for the highest one, they will all have finished their periods, and meet at one for a new series. This is an illustration, in the low silence of pendulum-oscillations, of what constitutes the System of musical vibration in the much higher region of vibrating strings and other elastic bodies, and determines the number of undeveloped sounds which form the harmonious halo of one sound, more or less faintly heard, or altogether eluding our dull mortal ears; and which determines the number of sounds which, when developed, constitute the System of musical sounds." [Scientific Basis and Build of Music, page 16]

"Things are not always what they seem. Common sense, so very valuable in every-day life, goes but a very little way in science. Common sense could not have told that, when a uniform body is suspended at one end and oscillated as a pendulum, the oscillations would be the same if suspended at one-third from the end. Much less could common sense have told that suspension at a point between these two points, namely, at two-thirds of this one-third from the end, would give the highest rate of speed of oscillation of which the body is capable, a point which we shall call the center of Velocity." [Scientific Basis and Build of Music, page 18]

"the other, like as we also reckon the vibrations of a pendulum." Holden adds that Dr. Smith, in his Harmonics, reckons the complete vibration to be double of this. Lees, in his Acoustics, says- "The travel of a vibrating elastic body from one extreme to the opposite and back again is called a vibration. Continental writers define a vibration to be the travel of a vibrating body from one extreme position to the opposite. This corresponds to our definition of the oscillation of a pendulum." [Scientific Basis and Build of Music, page 23]

"If we take a pendulum which goes from side to side 60 times in a minute, and another which goes from side to side 120 times in a minute, these two pendulums while oscillating will come to their first position 30 times during the minute. Now, if an oscillation is to be considered a natural operation, like the revolution of a wheel, or that of a planet in its orbit, which is completed when it returns to the place where the revolution began, then the pendulum's oscillation is not completed till it returns to the place of starting; and thus defined the oscillations of these two pendulums in the minute are not 60 and 120, but 30 and 60; 30 is the unit of measure in this case - 30 is the 1, and 60 is the 2; and this would establish the ratio of 1 to 2 in these two pendulums. And what is true in the ratio of 1 to 2 is true also of every other ratio, in this respect. This is a natural basis to work on, and defines the oscillation of a pendulum to be its excursion from extreme to extreme and back." [Scientific Basis and Build of Music, page 25]

pendulum where fourth the length is double the oscillations. A third condition in this order is in springs or reeds where half the length is four times the vibrations. If we take a piece of straight wire and make it oscillate as a pendulum, one-fourth will give double the oscillations; if we fix it at one end, and make it vibrate as a spring, half the length will give four times the vibrations; if we fix it at both ends, and make it vibrate as a musical string, half the length will produce double the number of vibrations per second. [Scientific Basis and Build of Music, page 80]

See Also


Rhythmic Balanced Interchange
Ramsay - The New Way of Reckoning a Pendulum Oscillation
Rotation and Revolution are Reciprocals
Sine Wave
Vibration
Vortex
Wave
Wave Field
7.2 - Rhythmic Balanced Interchange
8.2 - Oscillation versus Vibration

Created by Dale Pond. Last Modification: Tuesday November 24, 2020 05:32:12 MST by Dale Pond.