If all the companies be present, and the formation in three ranks, the depth of column will be twelve files; if in two ranks the depth will be eight, files.

If the flank companies be detached, the depth of column will be, for three ranks nine files, and for two ranks six files.

(Figs.

27 and 28.) In the Russian service each, battalion has four divisions of three ranks each.

But the third rank is employed as tirailleurs, which gives a depth of column of eight files.