“That is what may be termed the usual formation. Conditions may be such that it would be desirable to make the advance party stronger; as where the enemy habitually opposes us with relatively small detachments and we want to run over them and drive them off without bringing the support into action. “In any case you must have a knowledge of the functions of an advance guard. You must know the mission and be able to size up the situation of the particular case. You must then use your plain commonsense in meeting the situations as they develop. “_Duties._—Now let us see what the duties of the advance guard are: “1. To prevent the main body of our troops from being fired into while they are in a formation that prevents them from defending themselves. You can imagine what would happen if an effective fire were suddenly poured into the company while it is marching in column of squads on the road. “2. To gain information of the enemy by sending out detachments to the front and flanks at such points as may be necessary. Here is an important thing to remember. Under the conditions of modern warfare, the haphazard method of sending out flanking patrols has every chance of resulting in disaster. These men never get back in time to be of use to you when you need them. Much of this patrolling and marching of flanking detachments across country is exhausting and wears out your troops. It should be reduced to the minimum. “3. To push back small parties of the enemy. The progress of the main body must not be arrested by small, comparatively insignificant detachments of the enemy. It is the duty of the advance guard to brush them aside. How many times at maneuvers have you seen a skillfully handled patrol make a whole advance guard deploy? It should have been swept away by the advance party. The idea is, that you simply have to keep pushing to the front until you really encounter something that will stop you. “4. To check the advance of the enemy in force long enough for the main body to prepare for action. When the enemy is met in sufficient force to warrant the employment of troops of the main body there is a certain process that the commander has to go through before he can get his troops in action. A reconnaissance must be made to determine the strength and disposition of the enemy, for it would be folly to commit a force to action without knowing something of these elements. Then, too, the orders for the deployment have to be issued and the deployment has to be effected. All of this takes a certain amount of time during which period the advance guard holds off the enemy. “5. To remove obstacles, repair the roads, and favor in every way the uninterrupted progress of the main body.