1082

THEORY AND PRACTICE OF ENGINEERING.

Book II.

arrangement to maintain a perfectly horizontal action for the machinery, in whateversituation it might he applied. In the “ Traits complet de Mlcanique appliquee auxArts,” by M. J. A. Borgnis, some other machines for this purpose are described.

Fig. 1655. db cessart’s pile-cctter.

Louis Alexander De Cessart, who executed the celebrated breakwater at the Port ofCherbourg, described in a former part of this work, published an account of most of hisengineering works, among which is the detailed account of the dimensions and weight ofthe several parts of his machine for cutting off the heads of piles under water : as it is acurious document, and an example of the minute calculations entered into by French engineers for the construction of such kind of machinery, we have thought right to insertit; the dimensions are given in French feet, as the calculations in metres were not at thattime established.