For daytime signaling the United States Army favors the mirror or heliograph (sun-writing) system. The 1 is a short flash, the 2 is two short flashes, the 3 is a long, steady flash. This system can be read through 100 and 150 miles.
The United States Navy employs a two-arm or a two-flag system, which by different slants and angles of the arms or flags signals by the Army and Navy code. It is called the Semaphore system—like the semaphore block signals of railroads. It is more convenient for windy weather, because the flags are shorter and smaller than the flags of the three-motion wigwag.
Scouts should have in their library a copy of the United States Signal Corps booklet, "Manual of Visual Signaling," which can be had at a small price from the Government Printing Office at Washington. This tells all about the different systems of day and night signaling, and shows alphabets, signal flags, codes, ciphers, and so forth.
The Indians of the plains and mountains have had systems of signaling as perfect as those of the Army and Navy. In early days of the Army on the plains, the Indians passed news along among themselves over long distances faster than it was passed by the military telegraph. They used a smoke code; and they used also mirror-flashes, blanket-waving, pony-running, foot-running, and hand gestures.
Their secret signals were never told; no threats or bribes could make an Indian divulge his tribal or his band code. Not even the white men who lived with the Indians could learn it. Once some Army officers watched a Sioux chief, posted on a little knoll, drill his red cavalry for an hour, without a word or a gesture; all he used was a little looking-glass held in the palm of his hand.
However, some of the signs were general. A tremulous motion or flash meant game or enemy. Several quick flashes, close together, meant "Come on." A beam to the left meant "By the left"; to the right meant "By the right."
When looking for buffalo, the number of flashes would tell how many bands of buffalo were sighted, and a quivering motion would bid the hunters to "Come on."
Scouts will find some blanket signs handy. If the blanket is too large to manage, fold it once.
"Who are you?" Hold the blanket by the two upper corners, in front, and bend with it far to the right and to the left.
"We want peace." Hold the blanket by the two upper corners, in front, and bending forward lay it flat upon the ground.