PREFACE.

iv

...secondly because Mathematicians original: "Mathématiciens"; in the 18th century, this term often referred to theoretical scientists and natural philosophers who applied mathematical principles to study the laws of physics and nature. have not sufficiently applied to the perfection of the Arts original: "les Arts"; referring here to the "mechanical arts" or the practical application of skills in engineering, crafts, and construction. the consequences they could draw from their principles. For except for the Memoirs of the Royal Academy of Sciences, where one finds a great number of useful researches on all sorts of subjects, our Mathematical Books are written with such great dryness that it is not surprising that Practitioners The engineers, builders, and craftsmen who learned their trade through experience rather than formal schooling. find in them too little attraction to draw the knowledge that would be essential to them. They usually limit themselves to a few small Treatises on Geometry and Mechanics, and once they have learned the use that can be made of a few general propositions, they imagine they know enough. As for Algebra, they consider it fit only to serve as an amusement for those who have enough persistence to occupy themselves with difficult questions that lead to nothing.

However, as it is absolutely necessary to resolve an infinity of cases that present themselves every day in the construction of Works, it is to disabuse them of such an unjust opinion, and to show them the necessity of theory, that I have undertaken to write on Hydraulic Architecture The branch of engineering focused on the movement and management of water, such as canals, pumps, and naval construction., which is much more susceptible to theoretical application than civil architecture. Since no one is unaware of the importance of a subject that so closely concerns the needs of life, I believed that by applying myself to treating it with exactitude, I would be thanked for employing so usefully the moments of leisure at my disposal. I only fear that those who are not accustomed to the use of Algebra, and who have already complained about the amount I had included in my other Works, might murmur at finding so much of it in this one; but what would they have us do? It has become the key to all discoveries; it is not possible to do without it as soon as one wishes to act with precision. It is only by its means that one can deduce Methods to operate surely in the...