All was ready by the 16th of June, and Colonel Despard of the 99th Regiment began the second campaign against Heke, who had withdrawn to a _pa_ of immense strength at Oheawai, sixteen miles inland from the Bay of Islands. The colonel, an experienced soldier, commanded a force of six hundred and forty regulars from the 58th, 96th, and 99th Regiments; sailors from the _Hazard_; a company of one hundred volunteers, and two hundred and fifty friendly Maori. Four guns were with infinite pains hauled along the difficult track, through mud of a depth rarely seen in Britain, and over creeks and rivers with steep, defiant banks, between which the water often rushed in flood. June is midwinter in New Zealand, and no worse time could have been chosen for the expedition. Yet, in the judgment of those most deeply concerned with the colony's fortunes, it had to be undertaken. The force encamped near the mission-station on the Waimate or River of Tears, and on the 23rd of June marched to Oheawai, where a small garrison under Kawiti and Pene awaited their attack. Heke was still incapacitated. The night was spent in preparing batteries for the "potato pots," as the Maori styled the mortars with which it was intended on the morrow to breach the palisades of the _pa_,--four barricades of massive logs,[61] twenty feet in height, with a broad ditch between the first and the second. Some heavy hammering would be necessary before a path could be smashed through those tremendous defences. Yet it was confidently expected that the mortars would accomplish their part of the programme of attack. When they had turned in, the experience of the rest of the night must have been weird to the unseasoned British. Throughout the long, dark watches the comforting "All's well!" of the sentinels was drowned by the oft-repeated challenge, thundered by the guards in the _pa_, "Come on, O _hoia_![62] Come on and revenge your dead of Okaihau! Come on! Come on!" And the deep-toned, defiant watch-cry of Waka Nene's men from their hill, "Come on, O Nga-Puhi! Come on for your revenge! We have slain you in heaps ere now! Come on! Come on!" The bombardment began on the morning of the 24th, and for six days thereafter was continued. The round shot bowled through palisades one, two, three and four, or stuck fast in the giant posts; but never a trunk was shaken down, never one so hopelessly smashed as to open the door of that much-desired way. The enemy, safe in their cunningly contrived rifle-pits, meantime kept up a galling fire, which more than once caused a shifting of the positions of the batteries.