Whenever the progress of a train of waggons is arrested by the breaking down of any one of them, or other delay, all the waggons in the rear of the stoppage, should immediately drive up into the first open space, to as great a number as the open space will hold; this keeps the convoy together and better under the care of the escort.
The escort for a convoy should be divided into front, center, and rear guards; beside the divisions for the flanks, which should never be beyond musquet shot, or at most 400 yards from each other. The whole escort, should never be so separated that they could not be collected in an hour. Under proper precautions against an enemy, a convoy of any size cannot travel more than five or seven miles per day.
D ispart.—The dispart of a gun is the half difference between the diameter of the gun at the base ring, and at the swell of the muzzle. The general dispart of all guns is about the ¹/₅₆ part of their length. See the disparts of French and English guns under the word [Tangent Scale].
Fig. 1.
DISTANCES.—Inaccessible distances may be found several ways; the most correct of which of course is by means of proper mathematical instruments; which, however, are not always to be had in the field.
The following different methods are laid down by several authors, where instruments cannot be had.
I. Wishing to know the distance of the object A from B—([fig. 1.]) place a picket at B and another at C, at a few fathoms distance, making A B C a right angle, and divide B C into 4, 5, or any number of equal parts: make another similar angle at C, in a direction from the object, and walk along the line C D till you bring yourself in a line with the object A, and any of the divisions, (say o) of the line B C. Then, as Co : CD :: Bo : BA.
Vauban.