So the British man-of-war drew off, leaving the missionaries in the midst of danger. And almost immediately, with a great bursting roar, the bombardment from the French ships opened. Sometimes the shells flew high over the town and up to the bluff, so Dr. and Mrs. Mackay put their three little ones in a safe corner under the house; but they themselves as well as Mr. and Mrs. Jamieson, went in and out to and from the college, and the girls' school as though nothing were happening. Every day Mackay's work grew heavier and his anxiety for the persecuted Christians grew deeper. He ate very little, and he scarcely slept at all. It was not the noise of the carnage about him that kept him awake. He would have fallen asleep peacefully amidst bursting shells, but he had no opportunity. The whole burden of the young Church, harassed by persecution on all sides, seemed to rest upon his spirit. Anxiety for the Christians in the inland stations from whom he could not hear weighed on him night and day, and his brave spirit was put to the severest test. Only his great strong faith in God kept him up and kept up the spirits of the converts who looked to him for an example. And a brave pattern he showed them. Often he and A Hoa paced the lawn in front of the house while shot and shell whizzed around them. During the worst of the bombardment they came and went between the college and the house as if they had charmed lives. One day there was a great roar and a shell struck Oxford College, shaking it to its foundations. The smoke from fort and ships had scarcely cleared away when, crash! and the girls' school was struck by a bursting shell. Next moment there was a fearful bang and a great stone that stood in front of the Mackays' house went up into the air in a thousand fragments. But when the firing was hottest, Kai Bok-su would repeat to his students the comforting Psalm: "Thou shalt not be afraid for the terror by night; nor for the arrow that flieth by day." But in spite of his brave demeanor, the strain on the shepherd of this harassed flock was beginning to tell. And when the bombardment ceased and the intense anxiety for his loved ones was over, Kai Bok-su suddenly collapsed. Dr. Johnsen, the foreign physician of Tamsui, came hurriedly up to the mission house to see him. His verdict sent a thrill of dismay through every heart that loved him, from the anxious little wife by the patient's side, to the poorest convert in the town below. Their beloved Kai Bok-su had brain fever.