In the work before us, the nautical import of the terms is duly considered, and the orthography, as far as feasible, is ruled by authority and custom, with an occasional slight glance at the probable etymology of the words--slight, because derivation is a seductive and frequently illusory pilot. Our language is said to have been arraigned by foreigners for its hissing enunciation; but, regardless of the rebuke, our pundits have, of late, unnecessarily increased the whistling by substituting the sibilant _s_ for the vocal _z_, in all sorts of cases. Happily this same _s_ not being yet acclimatized to the galley, Jack will continue to give tongue to an enterpri_z_ing crui_z_e after Portugue_z_e merchandi_z_e, and there anent. The plan of our work may be said to comprise the treating _de omnibus rebus nauticis_, for many branches of knowledge are demanded of the intelligent seaman. Thus in Naval Architecture, the terms used in the construction of ships, the plans and sections, and the mechanical means of the builders, are undoubted requirements of a sea word-book. So also in Astronomy, or that portion of nautical science constituting observations which are necessary to the determinations of the navigator. In Mathematics, especially the branch distinguished as practical, the doctrine which teaches whatever is capable of being numbered or measured, requires verbal elucidation, not so much for the educated youth, as for him who labours under difficulties--who is "In canvass'd berth, profoundly deep in thought, His busy mind with sines and tangents fraught." Many of the words in our columns are not _de facto_ sea-terms, but as they are in rife and familiar use on ship-board, they obtained a lodgment; whence it becomes rather a difficult matter to mark a boundary for nautic language. Various expressions are also retained which, though unused or all but obsolete, occur so frequently in professional treatises and antiquated journals, that their exposition may often be welcomed by a general reader: they are here introduced, not as worthy of revival, yet as necessary to be understood when fallen in with. And it should be remembered, that--especially during our last conflict with France--so many combined enterprises occurred, that the most general naval and military phrases pertained, in a manner, to both arms of the service.