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.
The Indians, availing themselves of this fact, have been in the habit of practicing a system of telegraphing by means of smokes during the day and fires by night, and, I dare say, there are but few travelers who have crossed the mountains to California that ave not seen these signals made and responded to from peak to peak in rapid succession.
The Indians thus make known to their friends many items of information highly important to them. If enemies or strangers make their appearance in the country, the fact is telegraphed at once, giving them time to secure their animals and to prepare for attack, defense, or flight.
War or hunting parties, after having been absent a long time from their erratic friends at home, and not knowing where to find them, make use of the same preconcerted signals to indicate their presence.
Very dense smokes may be raised by kindling a large fire with dry wood, and piling upon it the green boughs of pine, balsam, or hemlock. This throws off a heavy cloud of black smoke which can be seen very far.
This simple method of telegraphing, so useful to the savages both in war and in peace, may, in my judgment, be used to advantage in the movements of troops co-operating in separate columns in the Indian country.
I shall not attempt at this time to present a matured system of signals, but will merely give a few suggestions tending to illustrate the advantages to be derived from the use of them.
For example, when two columns are marching through a country at such distances apart that smokes may be seen from one to the other, their respective positions may be made known to each other at any time by two smokes raised simultaneously or at certain preconcerted intervals.
Should the commander of one column desire to communicate with the other, he raises three smokes simultaneously, which, if seen by the other party, should be responded to in the same manner. They would then hold themselves in readiness for any other communications.
If an enemy is discovered in small numbers, a smoke raised twice at fifteen minutes’ interval would indicate it; and if in large force, three times with the same intervals might be the signal.
Should the commander of one party desire the other to join him, this might be telegraphed by four smokes at ten minutes’ interval.
Should it become necessary to change the direction of the line of march, the commander may transmit the order by means of two simultaneous smokes raised a certain number of times to indicate the particular direction; for instance, twice for north, three times for south, four times for east, and five times for west; three smokes raised twice for northeast, three times for northwest, etc., etc.
By multiplying the combinations of signals a great variety of messages might be transmitted in this manner; but, to avoid mistakes, the signals should be written down and copies furnished the commander of each separate party, and they need not necessarily be made known to the other persons.
During the day an intelligent man should be detailed to keep a vigilant look-out in all directions for smokes, and he should be furnished with a watch, pencil, and paper, to make a record of the signals, with their number, and the time of the intervals between them.