Besides, if small columns are employed, the whole country will be, in the first instance, over-run, and the enemy may, on account of the apparent weakness of the various detachments, take heart of grace and fight.
This, after all, is what is most desired, for the aim is always to attain rapid and decisive victory, and so end the campaign.
An argument against convergent invasion is, that since it may be necessary to use more than one line of communication, not only will the employment of larger numbers be necessary, but more transport animals, the provision and care of which really constitutes the main difficulty in frontier warfare, will be required.
This drawback may, however, be mitigated by opening only one line of communication, along the easiest route, the other detachments moving as flying columns, until the heart of the district is reached, when their surplus animals can be transferred to line of communication duties.
STRENGTH AND ORGANISATION OF COLUMNS.
In deciding the strength of a column for an expedition against the North West Frontier tribesmen, the first requisite, having regard to the foregoing considerations, is so to limit numbers, that, in the topographical conditions likely to be met, the force can, as an entirety, make a march of reasonable length, let us say eight or ten miles. Assuming that the column will move at an average rate of about two miles per hour, that, in order to avoid risk of disaster, it is, as a rule, desirable for the main force not to march before dawn, and to be in camp by dusk, and that ten—twelve hours of daylight are available, it is clear that the road space occupied must not, for a ten mile march, exceed ten to fourteen miles. That is to say, the numbers that can fulfil this condition on a narrow track, amount to about 4500 fighting men, carrying three days' rations on the person, and five days' on transport animals.
Suppose that four such columns are destined to invade the Afridi Tirah.
The Afridis are said to possess 25,000 to 30,000 fighting men, and if it be assumed that two-thirds of these have breech loading rifles, and that the whole mass is unlikely to attack any, one, or even two columns, the largest hostile gathering that a British detachment may expect to meet is 6000-8000 men, of whom 4500-5500 may be well armed.
A column of 4500 disciplined troops need not therefore fear reverse.