On War

by Carl von Clausewitz

Nowadays, even if the army is to fight as a whole, columns need no longer be kept together so as to be able to join up before the action begins. They can do so while the engagement is in progress.

Arithmetically speaking, the dangers of subdivision are in inverse ratio to its necessity The smaller the units, the more likely they are to have to go to one another's help. The larger they are, the longer they can look out for themselves.

in planning a march, there will be no major problems that could render speed and punctual arrival incompatible with a proper concentration of strength.

in modern war it is no longer very difficult to organize a march. Prompt and rapid marches no longer require the special skill and the wealth of local knowledge which Frederick the Great, for instance, had to apply during the Seven Years War.

Modern armies have long been accustomed to consider a fifteen-mile march as a day's work. In extensive operations it must be reduced to an average of ten miles in order to allow for the requisite days of rest on which necessary repairs and maintenance can be carried out.

Forced marches, if undertaken one at a time, may cover twenty-five miles, or thirty at the most; if they continue, only twenty.