An impulse can be soft or hard or in between. In the case of a soft impulse such as a soft rubber mallet impacting a bell few harmonics are created. With a hard impulse such as a steel hammer on a bell the power of impact develops countless harmonics via the Law of Cycles. (see Syntropy, Principle of Regeneration)
Keely "When the proper impulse is given to induce the rotation with pure alternating corpuscular action, the conditions of action become perpetual in their character, lasting long enough from that one impulse to wear out any machine denoting such action, and on the Sympathetic Stream eternally perpetual. The action of the neutral or focalizing centers represents molecular focalization (syntropy) and redistribution (entropy), not having any magnetism associated with them; but when the radiating arms of their centers are submitted to the triple compound vibratory force, representing their mass thirds, they become magnetic and consequently cease their rotation. Their rotation is induced by submitting them to three different orders of vibration, simultaneously giving the majority to the harmonic third." [Keely in Keely and His Discoveries]
"Keely teaches that an unknown potency is held in the atom's tenacious grasp until released by an introductory impulse given by a certain order of vibration, depending upon the mass-chord of the aggregation; which impulse so increases the oscillation of the atoms as to rupture their etheric capsules." [Bloomfield-Moore]
"Luminiferous ether," he writes, "or celestial mind force, a compound interetheric element, is the substance of which everything visible is composed. It is the great sympathetic protoplastic element; life itself. Consequently, our physical organisms are composed of this element. This focalizing, or controlling media, of the physical, has its seat in the cerebral convolutions; from which sympathetic radiation emanates. This sympathetic outreach is mind flow proper, or will force; sympathetic polarization to produce action; sympathetic depolarization to neutralize it. Polar and depolar differentiation, resulting in motion. The true protoplastic element sympathetically permeates all forms and conditions of matter; having, for its attendants, gravity, electricity, and magnetism; the triple conditions born in itself. In fact, it is the soul of matter; the element from which all forms of motion receive their introductory impulse." [Vibratory Physics - The Connecting Link between Mind and Matter]
"Inaudible vibrations are tested by the magnetic needle and sound colours. Every gaseous molecule is a resonator of itself and is sensitive to any and all sounds induced, whether accordant or discordant. At the normal density of the atmosphere we hear a volume of sound, focalized by the combined association of every molecule brought under sound influence. When we reduce the atmospheric volume of a chamber to 50/100, then the ear is sensitive to the reduction of the acoustic force evolved on the same ratio, and so on, until sound becomes inaudible. This inaudibility to our organ of hearing is no proof whatever of any reduction of the acoustic force evolved on the introductory impulse given to the bell. If is only a proof that the number of the molecules left for the acoustic force to act upon has been so reduced by increasing the acoustic force, that the concentration of sound from the diminished number cannot be heard. The ear is not susceptible to the acoustic force emanating from one molecule, nor even from the concentration of one hundred millions of billions molecules. The highest acoustic force that can be induced, taking but a cubic inch in volume to act upon, will leave a residual number of molecules one hundred billion times as great as the above given number and yet be perfectly inaudible when all their acoustic force are focalized." [Vibratory Physics - The Connecting Link between Mind and Matter]
"In theorizing on the philosophy of planetary suspension Mr. Keely writes:- "As regards planetary volume, we would ask in a scientific point of view - How can the immense difference of volume in the planets exist without disorganizing the harmonious action that has always characterized them? I can only answer this question properly by entering into a progressive synthesis, starting on the rotating etheric centres that were fixed by the Creator with their attractive or accumulative power. If you ask what power it is that gives to each etheric atom its inconceivable velocity of rotation or introductory impulse, I must answer that no finite mind will ever be able to conceive what it is. "The philosophy of accumulation", assimilation, Macvicar calls it, "is the only proof that such a power has been given. The area, if we can so speak of such an atom, presents to the attractive or magnetic, the elective or propulsive, all the receptive force and all the antagonistic force that characterizes a planet of the largest magnitude; consequently, as the accumulation goes on, the perfect equation remains the same. When this minute centre has once been fixed; the power to rend it from its position would necessarily have to be as great as to displace the most immense planet that exists. When this atomic neutral center is displaced, the planet must go with it. The neutral center carries the full load of any accumulation from the start, and remains the same, for ever balanced in the eternal space.''" [More Science]
Cayce "Now, respecting the conditions regarding motor, and motive forces or powers in the activity of that as is set forth, both in that as builded and that as contemplated - while it becomes necessary for the stabilizing of the energy that is created in the active forces of the integration and disintegration of the elements, in the active force of gravitation produced in the motive energy that is to be expanded in motor - it is well that these be changed to meet the needs of such stabilization, and with the ability to control the force and power created. But to change from the chemical activity, that brings the force to act with the expansion in gravitation, would be to defeat the purpose of that as being created. While the drawings, and the constructive force, may carry out the principle in action, there must be that motive power to create the first active force. And this will only act in the way as has been set up.
"Make the stabilizing power or element stable, and not to leave out the chemical reaction that must begin the activity from the place of the operating element. When one pulls, the other must pick up, and it must be as the gravitation in its action to create this." Cayce (195-61) see Cayce Perpetual Motion Machines