The Commandant played well. He needed no notes, for he was stored with remembered bits. He often played to them of an evening, before he took his turn on watch. He played quietly along for a little. Out of the dark at their north window, there came the piping of a night bird. Birds were the only creatures seemingly untouched by the war. The fields were crowded thick with the bodies of faithful cavalry and artillery horses. Dogs and cats had wasted away in the seared area. Cattle had been mowed down by machine guns. Heavy sows and their tiny yelping litter, were shot as they trundled about, or, surviving the far-cast invisible death, were spitted for soldiers' rations. And with men, the church-yard and the fields, and even the running streams, were choked. Only birds of the air, of all the living, had remained free of their element, floating over the battling below them, as blithe as if men had not sown the lower spaces with slaughter. And now in this night of spring, one was calling to its mate. The Commandant heard it, and struck its note on the upper keyboard. "Every sound in nature has its key," he said; "the cry of the little bird has it, and the surf at Nieuport." "And the shells?" asked Hilda. "Yes, the shells, they have it," he answered gravely; "each one of them, as it whistles in the air, is giving its note. You have heard it?" "Yes," answered Hilda. "Why, this," he said. He held his hands widely apart to indicate the keyboard--"this is only a little human dipping, like a bucket, into the ocean waves of sound. It can't give us back one little part of what is. Only a poor, stray sound out of the many can get itself registered. The rest drift away, lost birds on the wing. The notes in between, the splintered notes, they cannot sound on our little instruments." A silence had fallen on the group. Out of the hushed night that covered them, a moaning grew, that they knew well. One second, two seconds of it, and then the thud fell somewhere up the line. As the shell was wailing in the air, a hidden string, inside the frame, quivered through its length, and gave out an under-hum. It was as if a far away call had rung it up. One gun alone, out of all the masked artillery, had found the key, and, from seven miles away, played the taut string. "There is one that registers," said the Commandant; "the rest go past and no echo here." Firmly he struck the note that had vibrated. "That gun is calling for me," said he; "the others are lost in the night. But that gun will find me." "You talk like a soothsayer," said Mrs. Bracher, with a sudden gesture of her hand and arm, as if she were brushing away a mist. "It's all folly," she went on, "I don't believe it. Good heavens, what is that?" she added, as a footstep crunched in the hall-way. "You've got me all unstrung, you and your croaking." An orderly entered and saluted the Commandant.