As she sauntered along, doing nothing in particular, she noticed Mabel, who was standing under an orange tree close to the wall.

At the same moment, advancing towards them came the sound of Rachel's voice caroling an old English song.

Now there is nothing in the least wrong or unorthodox in standing under an orange tree, yet the instant Irene glimpsed Mabel's face she was certain her schoolmate was in that particular spot for some reason the reverse of good.

She looked uneasily at Irene, glanced in Rachel's direction, seemed to hesitate, and finally took to her heels and bolted away through the bushes.

Next minute, over the top of the high wall descended a little parcel.