As soon as the Indians are discovered in their bivouac, the pursuing party should dismount, leave their horses under charge of a guard in some sequestered place, and, before advancing to the attack, the men should be instructed in signals for their different movements, such as all will easily comprehend and remember. As, for example, a pull upon the right arm may signify to face to the right, and a pull upon the left arm to face to the left; a pull upon the skirt of the coat, to halt; a gentle push on the back, to advance in ordinary time; a slap on the back, to advance in double quick time, etc., etc. These signals, having been previously well understood and practiced, may be given by the commander to the man next to him, and from him communicated in rapid succession throughout the command. I will suppose the party formed in one rank, with the commander on the right. He gives the signal, and the men move off cautiously in the direction indicated. The importance of not losing sight of his comrades on his right and left, and of not allowing them to get out of his reach, so as to break the chain of communication, will be apparent to all, and great care should be taken that the men do not mistake their brothers in arms for the enemy. This may be prevented by having two _pass-words_, and when there be any doubt as to the identity of two men who meet during the night operations, one of these words may be repeated by each. Above all, the men must be fully impressed with the importance of not firing a shot until the order is given by the commanding officer, and also that a rigorous personal accountability will be enforced in all cases of a violation of this rule. If the commander gives the signal for commencing the attack by firing a pistol or gun, there will probably be no mistake, unless it happens through carelessness by the accidental discharge of firearms. I can conceive of nothing more appalling, or that tends more to throw men off their guard and produce confusion, than a sudden and unexpected night-attack. Even the Indians, who pride themselves upon their coolness and self-possession, are far from being exempt from its effects; and it is not surprising that men who go to sleep with a sense of perfect security around them, and are suddenly aroused from a sound slumber by the terrific sounds of an onslaught from an enemy, should lose their presence of mind. TELEGRAPHING BY SMOKES. The transparency of the atmosphere upon the Plains is such that objects can be seen at great distances; a mountain, for example, presents a distinct and bold outline at fifty or sixty miles, and may occasionally be seen as far as a hundred miles.