To find a power that will aid the motion of the pendulum, and in conjunction renew its strength, is what is wanted to create perpetual motion. What I shall endeavor to explain will at least induce towards the discovery of this power. The principal parts of the machinery about to be shown are in number three: A vibrating pendulum. A revolving pendulum, and A tubular lever. A vibrating pendulum in motion describes a segment of a circle, and returns on the same segment, and at every vibration its described segment decreases. A revolving pendulum is composed of two or more pendulums, united at their lighter extremities, there revolving on an axis, the heavier extremities being placed at equal distances in the outer circle: this, I believe, is what is termed a fly-wheel when affixed to hand-mills, etc. The tubular lever is the chief instigator of the whole, and must contain a weight apportioned to the weights of the two pendulums. Fix the lever on a cross axis; thus, on an axis within a circle, the circle on an axis at opposite angles, thereby is given to each extremity of the lever a revolving power of motion; attach one extremity of the lever to the outer circle of a revolving pendulum, the other extremity confine within the bar of the vibrating pendulum; thus combined, the effect to be produced when put in motion will be this: The two pendulums will guide the motion of the lever, which then partakes of the power of a pendulum, giving fresh impulse at every vibration of the pendulum, and every half revolution of the revolving pendulum; for, as each extremity of the lever rises, the weight within falls to the opposite extremity, and gives fresh impulse to the whole: thus (if my idea is correct) will be produced motion perpetual--that is to say, perpetual so long as the materials of which it is made will hold together. I have given this short description merely by way of example, as I believe there are several ways of combining these three powers, so as to produce perpetual motion, if my idea on the subject is correct. The lever may contain mercury or a solid orb of heavy substance; and if the tube be exhausted of air the weight will pass more freely, and certainly increase the power of the lever. J. Welch In 1825 the following article was published in "Mechanics' Magazine," having been contributed by J. Welch: