Pontonier, or Pontonnier. A soldier having the charge of constructing bridges.
Pontons. A kind of portable boats specially adapted for the formation of floating bridges required by armies. They are constructed in various ways, of wood, metal, or prepared canvas, stretched over frames made for the purpose (the latter it is said are much in favor), and have the necessary gear placed with them for transport. The ponton used in the U. S. army is constructed as follows:
The ponton frame is composed of two side frames, of twelve narrow and of two wide transoms. The former are strengthened at the ends by iron straps, which are countersunk and perfectly smooth; all the edges of the frame and transoms are well rounded to prevent chafing the canvas. The wide transoms are of 10-inch by 11⁄2-inch plank, provided with tenons to fit the mortises in the frame. The narrow transoms are of 4-inch by 21⁄2-inch scantling. The articles of each of the above classes are made exactly alike, so that they may be interchanged. Two of the narrow transoms are provided with an iron mooring becket.
The frame when assembled is held together by a rope passed through the rings in the ends of the side frame, and tightened with a rack-stick.
The ponton cover is of 0000 cotton duck, double-seamed, with the border double for 11⁄2 inches in width. The clew-line eyelets are of metal. The lashings are of 1-inch rope 18 feet in length, and looped at one end, and the cable used is of 3-inch Manilla rope, 30 fathoms long.
Bridge Equipage.—The United States bridge equipage is composed of reserve and of advance-guard trains. The former are intended to accompany large bodies of troops in the field, and are provided with the material necessary for the construction of bridges of sufficient capacity to pass large armies with their heaviest trains over rivers of any size and rapidity.
The advance-guard equipage is intended for the use of light troops, such as advance-guards, cavalry expeditions, etc. It is organized, both as regards material and carriages, with a view to rapidity of movement. At the same time, it is capable of furnishing a bridge which will fulfill all the requirements of troops engaged on such service.
Organization.—The reserve equipage is divided into trains, each of which is composed of four ponton divisions and one supply division. Each division is accompanied by tool-wagon and traveling-forge.
Each ponton division is complete in itself, containing all the material necessary for constructing a bridge of eleven bays, or 225 feet in length.
Each of these divisions is subdivided into four sections, two of which are ponton and two abutment sections; the former contain three ponton-wagons and one chess-wagon; the latter, one ponton-, one chess-, and one trestle-wagon each.