vij

PREFACE.

to embrace generally everything that related to the manner of conducting, raising, and managing Water original: "Eaux"; referring here to the broad field of hydraulic engineering, including irrigation, fountains, and supply systems., without troubling myself with the length of the labor, nor the dissatisfaction that the delay in the printing of my Work would cause; persuaded that when it appeared, I would be thanked for having made my efforts to deserve the good opinion that the Public showed it had formed by its impatience to see it appear. Furthermore, in order not to bore with a longer detail, let it be known that I have divided it into two Parts; as the present concern is only with the first, comprised of four Books, here is its objective.

The first Book is an Introduction to the entire Work: it was believed that for the understanding of those who were ignorant of the Principles of Mechanics, or who, having learned them, did not have them present enough in mind to feel their application; it was appropriate to begin by giving them a Preliminary Treatise, written in such a way that they can form a correct idea of the different movements encountered in compound Machines original: "Machines compoſées"; machines that utilize a combination of two or more simple machines, such as levers, pulleys, or screws., to calculate their effect regardless of the directions of the power and the weight original: "puiſſance & du poids"; in 18th-century physics, "power" refers to the input force applied to a machine, while "weight" refers to the load or resistance to be moved.. This Treatise is accompanied by the theory of motion and the impact of bodies original: "choc des corps"; the study of how forces are transferred during collisions, which is vital for understanding how moving water strikes the blades of a waterwheel., in order to deduce the Rules of Hydraulics by shorter and clearer paths than those followed until now.

Next, we examine the resistance caused by friction original: "frottement"; the force resisting the relative motion of solid surfaces or fluid layers sliding against each other., and the manner of calculating the loss original: "déchet"; specifically, the loss of mechanical efficiency or power resulting from friction and other resistances. in all sorts of cases, to account for it in practice. This Subject is treated thoroughly and applied to examples fit to gradually enlighten the mind regarding the advantages and defects of all Machines: we have added Maxims General rules or fundamental principles derived from experience. on what must be observed when one wishes to create a project, and to put the Reader in a position to do so by himself in