These precautions were not superfluous, as the cathedral was repeatedly made the target of enemy artillery fire. In 1915, during an air bombardment, three out of nine bombs fell in the immediate vicinity, at distances varying from 150 to 200 yards. In the spring of 1918 an incendiary shell burst in the Rue de Robert Luzarches, within 30 yards of the Virgin doorway, completely destroying two houses, while splinters hit the upper part of the doorway above the wall of sandbags. In all, nine shells hit the cathedral, but none of them caused very serious damage.
The roof was pierced in several places, particularly on the south side of the choir, and the vault was perforated in the south aisle of the choir and in the nave. The gallery of the triforium was likewise torn open on the south side of the nave, while the chapels of St. John the Baptist (photo p. 32) and Our Lady of Faith (D 1 on plan) were damaged. Outside, the façades were struck with shell splinters, while here and there buttresses, flying-buttresses, and mullions of windows were broken or damaged.
(See outline opposite [p. 9 ]and plan opposite [p. 8]).