the cultivated countries of central Europe there are, generally, lateral roads which can be used for a march, so that there is no necessity to go across country, as was so often done in the Seven Years’ War.
Again, it is known by experience that the head of a column composed of four divisions and a reserve of cavalry, even on indifferent roads, generally gets over a march of three miles in eight hours; now, if we reckon for each division one league in depth, and the same for the reserve cavalry and artillery, then the whole march will last thirteen hours. This is no great length of time, and yet in this case forty thousand men would have marched over the same road. But with such a mass as this we can make use of lateral roads, which are to be found at a greater distance, and therefore easily shorten the march. If the mass of troops marching on the same road is still greater than above supposed, then it is a case in which the arrival of the whole on the same day is no longer indispensable, for such masses never give battle now the moment they meet, usually not until the next day.