Talk:Thomas Newcomen/Material from Wikipedia user Dr. Gabriel Gojon/The Development of Dynamics

The Development of Dynamics Equipped with a matter containing unlimited resources ("slumbering parts which must yet be awakened"), Leibniz transcended the science of mechanics that had dominated Western thinking since Archimedes. Where mechanics pertained to the passive effects of ancient machines-- the lever, pulley, inclined plane, etc.-- dynamics was conceived as the science of the active, living force (vis viva, or kinetic energy) of "violent actions" - like the explosion of gunpowder, and rapid expansion of high pressure steam: "The ancients, so far as is known, had conceived only a science of inactive force, which is commonly referred to as Mechanics, dealing with the lever, the windlass, the inclined plane pertinent to the wedge and screw though there is discussion of the equilibrium of fluids and of similar problems; only the effort or resistance of bodies and not the impetus they have acquired through their action, is discussed .... "For I here refer not to any effect, but to one produced by a force which completely expends itself and may therefore be called violent; such is not the case with a heavy body moving on a perfectly horizontal plane and constantly preserving the same force; this is a harmless sort of effect, so to speak, which we can also calculate by our method, but it is not the one we wish to consider now."

Since it is limited to the study of "harmless sorts of effects," mechanics considers the total absolute force of bodies acted upon by the ancient machines, as directly proportional to the acquired velocity, or F = mv. In contrast, Leibniz considered the equivalence of the kinetic energy of a heavy body falling from a given height (violent action), to the work required to raise it to that height, and determined that the live force of a body in motion is directly proportional to the square of the velocity; that is, F (proportional to) mv². Leibniz's practical goal became to harness the most violent actions, for the purpose of advancing the material conditions of man. By applying the law of the conservation of vis viva to maximize the conversion of the kinetic energy of such actions into useful work, Leibniz envisioned mastering the direct force of explosions to power ships, carriages, airplanes, and factories. In contrast, how could a scientific establishment possibly invent anything useful while insisting, as the British Royal Society did throughout this period, that one's preference between measuring force by mv or mv² is simply a matter of personal taste, the consequence of a mere semantic quibble?

From the beginning of his study of the matter, Leibniz had insisted on the practical implications of his dynamics, particularly the issue of mv² versus mv, for the construction of machines and the perfection of technology. He wrote in 1695:

These things are not worthless to consider, nor are they quibblings over words, for they are of the greatest importance in comparing machines and motions. For example, if power is obtained from water or animals or from some other cause, by which a weight of 100 pounds is kept in constant motion so that within a fourth of a minute it can be made to complete a circle of 30 feet diameter, but someone else maintains that a weight of 200 pounds can in the same time complete half the circle with less expenditure of power, his calculation seems to yield a gain; but you ought to know that you are being deceived and getting only half the power .... By 1675, the impact of the reactionary shift in the policies of Louis XIV, which began with the French invasion of Holland in 1672, reached Colbert's Academy. The result was a forced exodus of Protestant scientists. Leibniz left Paris reluctantly to accept a post as librarian in Hanover, while Papin left for England.