A Military Dictionary and Gazetteer / Comprising ancient and modern military technical terms, historical accounts of all North American Indians, as well as ancient warlike tribes; also notices of battles from the earliest period to the present time, with a concise explanation of terms used in heraldry and the offices thereof. The work also gives valuable geographical information. Compiled from the best authorities of all nations. With an appendix containing the Articles of war, etc.

by Thomas Wilhelm

Principes. In the Roman armies, were the infantry, who formed the second line in the order of battle. They were armed like the hastati, with this difference, that the former had half-pikes instead of whole ones.

Principles, Military. The basis or ground-work upon which every military movement is made, and by which every operation is conducted.

Prismatic Compass. A surveying instrument, much used on account of its convenient size and form in military sketching, and for filling up the details of a map where great accuracy is not required.

Prismatic Powder. See [Gunpowder].

Prisoners. Are persons under arrest or in custody, whether in prison or not. Whenever any officer is charged with a crime, he is to be arrested and deprived of his sword by the commanding officer; and soldiers charged with crimes are to be confined until tried by a court-martial, or released by proper authority. (See Appendix, [Articles of War], [65] and [66].) When brought into court, a prisoner should be without irons, or any manner of shackles or bands, unless there is danger of an escape, and then he may be secured with irons.—Blackstone.

Prisoners of War. Are soldiers captured during an engagement, siege, or continuance of hostilities, who are deprived of their liberty until regularly exchanged.

Prisons, Military. Are buildings constructed for the retention of prisoners of war, or for the safe-keeping and punishment of offenders against military law. Sometimes during war forts and other strong buildings are utilized for these purposes. The following were noted prisons during the civil war, 1861-65, for the retention of Federal prisoners of war:

[Andersonville] (which see).

Belle Isle.—An island in the James River near the city of Richmond, Va. The unfortunate prisoners taken were placed on this island without shelter of any kind to protect them from the scorching rays of the sun during the day or the chilly cold mists of the night, until death or exchange released them from their sufferings.

Castle Thunder.—A fort in Charleston harbor, S. C., which was used for the same purpose.