PREFACE.

...a number of skilled people from every country where necessity has suggested means of avoiding a common evil or procuring a general good; having maintained a correspondence with all those who could provide us with assistance. Thus, it is the fruit of the meditations and long experience of the greatest Masters that forms the substance of this Treatise.

The difficulties ordinarily experienced when one wishes to build in water almost always come from the poor quality of the foundation, which most often must be drained dry. Therefore, we have begun with the details of everything that must contribute to the construction of the works, without neglecting the establishment of cofferdams original: "batardeaux." These are temporary, watertight enclosures pumped dry to allow construction work to take place below the waterline., nor the choice of machines for driving piles original: "pilots." Heavy timber stakes driven into the earth to provide a solid foundation in soft or waterlogged soil., the greater or lesser perfection of which leads to extreme consequences for the economy and speed of the work. Those who have considered these things only superficially will be surprised to see how much they are susceptible to an accurate analysis, and how necessary it is to know how to make good use of them.

Since sluices original: "écluſes." In this context, the term refers generally to water-control structures, including canal locks and tide gates. are the most essential part of Hydraulic Architecture, we have applied ourselves to developing them thoroughly throughout this first volume, of which they form the primary subject matter. As the size of their components has until now been purely arbitrary, we have subjected them to general rules, in the style of those established for the Orders of civil Architecture This refers to the Classical Orders (like Doric or Ionic), which are governed by strict proportional relationships.; that is to say, in imitation of Architects, who divide the lower semi-diameter of a column into a certain number of equal parts to determine the members of an Order, we have divided the width of the sluices into twelve modules original: "modules." A standard unit of measurement used to ensure all parts of a structure are in proportion to one another. to fix their own; and starting from this fundamental base,