A circle, therefore, is the most compact disposition for defence, and so most ideal for smaller numbers.

It is concentration in its most effective {p.188} form, while sacrificing nothing in elasticity and flexibility of motion.
These are the intrinsic defensive advantages--as distinguished from the offensive threat to the enemy's communications--secured to the weaker party by a permanent position, and these are its compensations for the loss of open communications which have been deliberately abandoned.
In Natal, at the end of October, 1899, the British army was much inferior to the enemy in both numbers and mobility; and while several lines of defence were to be found in the region behind, as was shown by the stubborn resistance which the Boers, when in turn outnumbered, made at the Tugela, these positions were open to the danger of being turned by superior numbers or superior rapidity; still more when these two were combined.

In fact, much of the subsequent Boer success in defence resulted from the fact that, acting on the inside of an arc, with the advantage of interior--shorter--lines, they also moved over the latter with greater speed, owing to their distinguishing characteristic as mounted troops.

They had particular facilities, in {p.189} a word, for accumulating successful numbers at a threatened point of a stationary defence, which the British would not have had in an active campaign of retreat.
It became therefore advisable, if not imperative, for the British commander in Natal to resort to a stationary defence for the preservation of his division, and to place himself for offensive purpose upon the flank of the enemy's possible line of invasion, in order to deter him from further advance.

As to situation, Ladysmith was clearly indicated by the reasons before stated, and especially because there was there accumulated a great quantity of ammunition, provisions, and other supplies, which not only should not be allowed to fall into the hands of the Boers, but also would be essential to the maintenance of the garrison, if relief were long delayed, as it proved to be.