DREDGERS are an extemely varied, albeit highly specialised, type of vessel, interesting alike to the naval architect, the engineer, and the shipbuilder. Literature on the subject of dredger design is, however, far from voluminous and, indeed, is remarkable mare for its paucity than for its fullness. There is abundant scope, then, for the volume by Mr. Dekker, and hfs description of a number of present-day dredging vessels and appliances forms a useful addition to the reference library of the practising engineer. It will b felt, on perusal, that the book is, in fact, mainly descriptive, and that it concentrates largely on iiidivkluai examples of dredger construction. This does not detract from the utility of the work as a practical directory to the subject, but it still leaves the field open for a dissertation on the principles underlying dredger design. Such a work would, perhaps, be the special province of the naval architect. Dredging and Dredging Appliances. By P. M. Dekker. Pp. xvi + 170. (London: Crosby Lockwood and Son 1927.) 36s. net.