It seemed ages before he reached the top, and that the noise he made must certainly attract the attention of the guard.

It did not.

We saw our comrade's.
figure outlined against the sky as he slid, over the top, and then heard the dull thump as he sprang to the ground on the other side.

"Number two," was whispered by our leader, and he performed the feat as successfully as his predecessor.

"Number, three," and he followed noiselessly and quickly.