the first shell landed at 7:18 a.m. on 23 March 1918 on the Quai de la Seine, the explosion being heard across the city. Shells continued to land at 15-minute intervals, with 21 counted on the first day. On the first day, fifteen people were killed and thirty-six wounded. The effect on morale in Paris was immediate: by 27 March, queues of thousands had started at the Gare d'Orsay and, at the Gare Montparnasse, ticket sales out of the capital were suspended due to demand. The initial assumption was these were bombs dropped from an airplane or Zeppelin flying too high to be seen or heard. Within a few hours, sufficient casing fragments had been collected to show that the explosions were the result of shells, not bombs. By the end of the day, military authorities were aware the shells were being fired from behind German lines by a new long-range gun, although there was initial press speculation on the origin of the shells. This included the theory they were being fired by German agents close by Paris, or even within the city itself, so abandoned quarries close to the city were searched for a hidden gun. Three emplacements for the gun were located within days by the French reconnaissance pilot Didier Daurat, the path of the shells which landed in Paris having revealed the direction from which they were being fired. The closest emplacement was engaged by a 34 cm railway gun while the other two sites were bombed by aircraft, although this failed to interrupt the German bombardment. Between 320 and 367 shells were fired, at a maximum rate of around 20 per day. The shells killed 250 people and wounded 620, and caused considerable damage to property. The worst incident was on 29 March 1918, when a shell hit the roof of the St-Gervais-et-St-Protais Church, collapsing the roof onto the congregation then hearing the Good Friday service. A total of 91 people were killed and 68 were wounded. There was no firing between 25 and 29 March, when the first barrel was being replaced; an unconfirmed intelligence report claimed that it had exploded. Barrels were probably changed again between 7-11 April and again between 21-24 April. The diameter of the later shells increased from 21 to 24 cm, indicating that the used barrels had been re-bored. A further emplacement, later identified as specifically designed for the Paris