A different form of the combination of defence with manoeuvre is the Defensive-Offensive battle, with examples of which the history of Warfare is amply supplied--Marengo, Austerlitz, and Waterloo being typical battles of this nature. In this form of defensive action a commander invites the enemy to attack a well-chosen position, and after exhausting the enemy's strength and holding up the assault, the commander passes from the guard to the thrust and overwhelms {77} the exhausted foe by an irresistible and sustained counter-attack with all the means at his disposal. A position is sometimes occupied as a matter of necessity, sometimes merely as a matter of tactical prudence. At _Nachod_ (June 27, 1866) the Prussian Advanced Guard hurriedly established a defensive position and kept at bay the whole Austrian Army, while the Prussian Army emerged in security from a defile and manoeuvred into battle array. The _Pass of Thermopylae_ was occupied in B.C. 480 by 1,400 Greeks under Leonidas, King of Sparta, to withstand the Persian hosts of Xerxes, and although the Greek force was destroyed by an attack from the rear (through the disclosure of a secret path by a renegade in the Persian service), the resistance offered to the "invincible" Persians emboldened the Greeks in their future encounters, and led to the ultimate defeat of the invaders. According to the legendary history of Rome, Horatius Cocles and two companions defended the _Sublician Bridge_ over the Tiber against Lars Porsena and the whole army of the Etruscans. This legendary heroism was equalled or surpassed during the _Second Battle of the Somme_ (March 21, 1918). "The bridges across the Crozat and Somme Canals were destroyed, though in some cases not with entire success, it being probable that certain of them were still practicable for infantry. Instances of great bravery occurred in the destruction of these bridges. In one case, when the electrical connection for firing the demolition charge had failed, the officer responsible for the destruction of the bridge personally lit the instantaneous fuse and blew up the bridge. By extraordinary good fortune he was not killed" (Sir D. Haig's Dispatches). At _Rorke's Drift_ (January 22, 1879) a force of 80 other ranks of the 24th Regiment, under Lieutenants Chard and Bromhead, with about 40 hospital cases, drove off the repeated attacks of 4,000 Zulus, part of Cetewayo's army which had surprised and annihilated the garrison {78} at _Isandhlwana_ earlier the same day. An astounding feat of arms was performed by a small body of troops during the withdrawal of the British Army in face of the overwhelming German attack at the _Second Battle of the Somme_. A detachment of about 100 officers and men of the 61st Brigade, 20th Division, was detailed to cover the withdrawal of their division at _Le Quesnoy_ (March 27,1918). Under the command of their Brigade-Major (Captain E. P. Combe, M.C.) the detachment