In one instance the device attracted the enthusiastic attention and elicited breathless interest from a doctor and surgeon of much more than ordinary skill and intelligence in his profession, and was hopefully regarded by a number of other persons who had had schooling advantages and were supposed to be versed in the rudiments of mechanics, and, it would seem to the author, ought at first sight to have perceived the fallacy and hopelessness of the inventor's dreams. All of these claimed inventions relying on the inclined plane with rolling weights were so nearly alike in the principle involved that all may be illustrated by the following explanation: [Illustration] The above figure shows a vertical section of a device that illustrates the controlling principle in all of these devices. It is manifest that the balls between A and C are hanging equally between A D and C D, the points of suspension A and C being in a horizontal line. It is also manifest that there will be a greater number of balls on the sloping incline A B than on the sloping incline B C. The Perpetual Motion seeker has always argued to himself that the _four_ balls between A and B should pull stronger to the left at B than the _two_ balls between B and C can pull. Sometimes this device has been varied whereby the balls would roll freely down the incline from B to A and then roll back toward C down another incline where they would be supposed to strike a lever and impel a ball from C to B, which ball would then roll down the incline B A, and so on indefinitely. The error of all this lies in the fact that the four balls between B and A will not elevate the two balls between B and C for the reason that they are on a less inclined slope. As we would ordinarily state it, B C is a "steeper" incline. One ball between B and C by force of gravity pulls stronger toward C than one ball on B A will pull toward A. It is manifest, therefore, that an equilibrium requires a greater number of balls on B A than B C. B A is longer and accommodates a greater number of balls than can be accommodated on B C. The number of balls that can be accommodated on the respective sides is always found to be such that the small number of balls between B C pull in the aggregate toward C the same as the greater number of balls between B and A pull toward A, and thus equilibrium is established. It is manifest, therefore, that with the pull from B toward C equal to the pull from B toward A, the mechanism finds its balance and motion ceases. This is true of all similar devices. CHAPTER III HYDRAULIC AND HYDRO-MECHANICAL DEVICES Enbom & Anderson's Pump "June 13, 1882 U. S. Patent, No. 259514 was granted to Andro Enbom and John A. Anderson, of Augusta, Kansas, U. S. A., on "Improvements in Pumps."