PREFACE.

...along with everything that may concern the preservation of dikes. We have no less applied ourselves to the manner of draining marshes, protecting against the causes that create them, constructing ponds, and directing canals and irrigation ditches, following the best practices used in Italy, Provence, and Switzerland.

The means of making rivers navigable, of containing them within their beds, and of preventing certain currents from encroaching upon neighboring lands, is a subject too interesting for us not to have made it an objective. As several Italian authors have written excellent things on this subject, we have profited greatly from their instructions. The King’s Engineers original: "Ingénieurs du Roi." These were the elite corps of military and civil engineers serving the French crown, often involved in massive infrastructure projects. in Alsace have their own specific method of building spurs original: "épis." Also known as groynes, these are low walls or barriers built out from a riverbank into the stream to redirect the current and prevent erosion of the shore. along the banks of the Rhine, to compel the river's current to follow the path most suitable for the preservation of the land; we report in the greatest detail what is practiced there.

A good portion of this work also concerns navigation canals; we mention those that have been executed or simply planned among all nations, by both the ancients and the moderns, and what must be observed when forming projects of such consequence, in order to take the most advantageous course. There is much to say on how to avoid unnecessary expenses, prevent the inconveniences inseparable from such undertakings, make a precise estimation of the water volume available, and the economy one must exercise when managing water drawn from the summit level original: "point de partage." In canal engineering, this is the highest point of a canal where water must be supplied to flow down both sides of a watershed divide., by ensuring, through a simple but little-known method,