At length, retreat being no longer possible, the rebel chief turned at bay and fought his pursuers at a point near the head of the valley. His decision to throw down the gage of battle here was not the result of accident or impulse, but was due to deliberate calculation. The position was admirably chosen, and he held the enemy in check long enough to enable him to fortify it effectively. He threw a rough breastwork of tree-trunks across the narrow neck of a spur springing from a densely wooded hill, the approach to which was flanked by steep ravines, leaving so narrow a ridge that it could only be passed abreast by a very limited force of men. This wooden rampart, which presented so imposing a front to an enemy, was liberally perforated with loopholes, through which the defenders were able to concentrate their fire with deadly effect upon any approaching force. This arrangement, combined with the inaccessible nature of the ground, made its seizure by storm practically impossible. Nevertheless, an attack was determined upon, and on the morning of August 6, 1846, fire was opened upon the position, but with no other visible result than that Ensign Blackburn[183] and two privates were killed and nine others wounded. On the following day the assault, which had been so inauspiciously commenced, was suspended, for Major Last had now seen enough to convince him that some projectile more searching than bullets was necessary to dislodge the defenders from their stronghold. He accordingly sent to Porirua and procured two small mortars, which, after infinite labour spent in dragging them into position, were discovered to be absolutely worthless for purposes of attack, for the high forest trees made accurate gunnery impossible. Seeing his troops in a deplorable condition, even after this short bush campaign, and hopeless of driving Rangihaeata out, except at an enormous sacrifice of human life, Major Last decided to withdraw the regular troops and leave the friendly natives, under Puaha, to watch and wait for hunger to work its effects upon the stubborn garrison. A few days sufficed for this. On the 13th the allies were surprised by a hail of lead suddenly raining down upon their lines. No sooner had they sprung to arms than they saw that the enemy was afoot, the volley which they had fired being the signal for retreat. Immediately the real nature of the movement was ascertained, Puaha and his loyalists rushed forward over the fallen trees and broken ground, and reached the breastwork only in time to see the last of the defenders escape by the thickly veiled forest track, where they were swallowed up by the bush and lost to human view.