_The regimental orderly_ BOOK contains the peculiar instructions of corps which are given by a colonel or commanding officer to the adjutant--hence _adjutant’s orderly_ BOOK--and from him to the serjeant-major, who delivers the same to the different serjeants of companies assembled in the orderly room for that purpose--hence the _company’s orderly_ BOOK. _The regimental_ BOOK is kept by the clerk of the regiment, and contains all the records, &c. belonging to the corps. _The Company_ BOOK, is kept by the commanding officer of every company; and contains returns of all incidents and payments. _The black_ BOOK is a sort of memorandum which is kept in every regiment, to describe the character and conduct of non-commissioned officers and soldiers; when and how often they have been reduced or punished, &c. Every quarter-master belonging to the cavalry and infantry, has likewise a book which may not improperly be called a book or inventory of regimental stores, &c. _Practice_ BOOK. Every officer of the artillery ought to have a book in which he should note every useful fact that occurs in practice. BOOM, in marine fortification, is a long piece of timber, with which rivers or harbors are stopped, to prevent the enemy’s coming in: it is sometimes done by a cable or chain, and floated with yards, topmasts, or spars of wood lashed to it. BORE, in gunnery, implies the cavity of the barrel of a gun, mortar, howitzer, or any other piece of ordnance. BOSSE, _Fr._ a term used in the French artillery, to express a glass bottle which is very thin, contains four or five pounds of powder, and round the neck of which four or five matches are hung under, after it has been well-corked. A cord, two or three feet in length, is tied to the bottle, which serves to throw it. The instant the bottle breaks, the powder catches fire, and every thing within the immediate effects of the explosion is destroyed. BOTTES, _Fr._ boots. _Grosses_ BOTTES, _Fr._ jack-boots. BOTTINE, _Fr._ half-boots worn by the hussars and dragoons in foreign armies. BOUCHE, _Fr._ means the aperture or mouth of a piece of ordnance, that of a mortar, of the barrel of a musket, and of every species of fire-arms from which a ball or bullet is discharged. BOUCHES _à feu_, _Fr._ is generally used to signify pieces of ordnance. BOULER _la Matiere_, _Fr._ to stir up the different metals which are used in casting cannon. BOULETS _à deux têtes_, chain-shot. BOULEVART, _Fr._ formerly meant a _bastion_. It is no longer used as a military phrase, although it sometimes occurs in the description of works or lines which cover a whole country, and protect it from the incursions of an enemy. Thus Strasburgh and Landau may be called two principal boulevarts or bulwarks, by which France is protected on this side of the Rhine. The elevated line or rampart which reaches from the Champs Elysées in Paris beyond the spot where the bastille was destroyed in 1789, is stiled the Boulevart.