So they all three went back to the museum, and here Morland placed desks and boxes together, and mounted on them so as to reach the trap-door, through which he wriggled. The girls held the pile steady, and watched his long legs disappear through the opening.
"It leads on to the roof!" he shouted. "I'll climb up and explore. I'm in a sort of garret with a ladder in the corner."
To the waiting girls it seemed a very long time before Morland returned. At last, however, they heard his footsteps overhead, and he called to them to hold the erection while he came down. It was with a sense of relief that they saw his boots issue through the trap-door. They had had an idea that he might have disappeared for ever.
"Well?"
"Did you see anybody?"
Morland shook his head. He was dusting his sleeves, and trying to rub the dirt off his hands.
"I didn't catch a burglar, but I've made a discovery," he said slowly.
"What?"
The girls were half-frightened, half-thrilled.
"I've been on the roof. Did you know the telephone wires run over the school?"