William Duane, A military dictionary
“ Rank, is a straight line made by the soldiers of a battalion, or squadron, drawn up side by side: this order was established for the marches, and for regulating the different bodies of troops and officers which compose an army.Doubling of the RANKS, is the changing one rank to two, by telling off the files, one, two, one, two, &c. and by the word, even files to the rear double; this method is frequently used in the manœuvres of a regiment.Rank and file, men carrying the firelock, and standing in the ranks, are called rank and file. ”
