If one has to deal with Infantry only, then, since their rate of march is almost always the same, it is easy to calculate approximately where the several columns may be found; but it is quite different when one comes to deal with Cavalry, where the different Leaders may adopt very different rates of movement, or may have such variations forced upon them by other circumstances, and hence one has always to deal with quite indeterminable factors. This difficulty can never be altogether eliminated; one can only counteract it by laying down from the very first instructions for the advance of the several columns, according to time and space, from which no deviation is to be permitted without sufficient reasons, and organizing the circulation of orders and intelligence in such a manner that it will work with certainty. These two precautions supplement one another. If one can calculate approximately where the several detachments are to be found at a given time, then reports can be sent by the shortest way, and will reach their destination without delay.
It will be decidedly advisable that all detachments should report to Headquarters, and if possible to all adjacent columns, without distinct instructions, and at certain time intervals, both as to their advance, their bearing in relation to adjacent columns, as also any news they may have obtained about the enemy.
Nothing is more important to the Cavalry Leader than to be constantly informed as to the general situation of the units he controls; but it is equally important that the several groups should know what is happening to one another, for only then can they act in the spirit and in combination with the whole.
This is all the more essential because, owing to the rapidity of all movements, and to the great extension which has often to be given to the front, it is impossible for the higher Command to interfere in good time, or to obtain information from its subordinates in any emergency that may suddenly arise. The results, then, depend entirely on the independent judgment of the man on the spot, and suitable action can only be obtained when the latter is kept fully informed as to the nature of the general situation.
We should, therefore, avoid as far as possible the despatch of orders to individual Commanders without at the same time informing their comrades of the bearing of such instructions.