phenomenon
was invariably as before: his white monastic robes would glimmer
through the darkness, glide up the stairway, and then seemingly melt
into nothing. Geraldine herself pursuing hotly on the scent, found that
she was utterly baffled.

A head girl, especially a prefect with a scorn for superstition, does
not like to admit herself baffled. Geraldine thought the matter over,
took Loveday into her confidence, and went to Miss Todd. As the result
of her interview she resolved to set what she called "a very neat little
spook-trap". She and Loveday said nothing about it to the rest of the
school. They merely bided their time.

Brother Lawrence did not always show up when anybody was on the watch
for him; he seemed to prefer displaying his supernatural powers to the
unwary. For two whole days he did not put in an appearance; whether he
was haunting elsewhere or expiating his sins in purgatory was a point
for discussion. On the third evening, however, Tattie, Jess, and Magsie
had screwed their courage to sticking-point, and strolled upstairs in
the twilight, half hoping and half fearing to catch a glimpse of the now
almost familiar apparition. They kept in the shadow of the big cupboard,
and held each others' hands without speaking. A full moon was shining
through the landing window, and lit up the narrow staircase with a
silvery, ghostly gleam. Suddenly from the darkness of a doorway emerged
the white robes, and passed rapidly upwards in the moonlight. Still
clutching hands for moral support, the three girls tore after it.
Surely this time they could manage to overtake it? But no; it had turned
the corner before they reached the lowest stair, and by the time they
had dashed up the ten steps it had made its usual disappearance. They
halted on the yard of landing, breathing hard; then their hearts seemed
to turn somersaults, for the attic door suddenly opened. It was no ghost
who peered forth at them, but Geraldine and Loveday. The former had a
candle in her hand; she struck a match and lighted it calmly.

"You needn't look so scared!" she said to the panting trio. "I'm just
going to show you your precious spook. Stand back a little, will you? I
assure you it won't bite you!"

She descended to the landing, turned round towards the four steps that
led to the attic door, then, to the immense amazement of the girls,
raised up the steps like the lid of a chest. There was a good-sized
cavity below, and in this place of co