ors there is wisdom.

However, Billy concluded to try the first old saw in working out his
plans, and the reader can judge for himself by the sequel whether he
took the wisest course or not.

After supper, when the boys were all supposed to be in the general
schoolroom, Billy got a chance to go up to the dormitories in order to
prepare for the little joke upon Jack.

The beds were all iron, with woven wire mattresses such as are used in
hospitals and preferable as being much more sanitary than the ordinary
wooden beds with slats of the same material.

Billy's idea was to loosen the side supports in such a manner that it
would not be obvious that anything had been done to them, but that the
bed would collapse as soon as any weight was put upon it and let the
occupant down upon the floor in the most summary fashion.

What he did was to lift up the sides and then to fasten them to the head
and foot pieces with very thin cord which was sufficient to hold them in
place only as long as there was no weight put upon them.

The instant that any one got upon the bed the side pieces would drop to
the floor and the occupant would go down with them, much to his
astonishment and the delight of the other boys.

Having fixed up his little trap, Billy replaced the clothes in as neat
a fashion as a chambermaid could have done, and there was apparently
nothing the matter with Jack's bed.

"That will be one on Master Jack for the ducking I got the other night,"
he said, and then he moved the washstand near enough to the bed so that
in the event of the latter's collapsing it would go down as well.

Satisfied with his work, he left the dormitory and returned to the big
schoolroom, his absence having caused no comment apparently, and his
presence and operations upstairs not having been noticed.

"There will be a nice little surprise party for some one at bedtime," he
said to himself, but did not let his satisfaction show on his face, so
that for all that appeared no one knew of the little trick.

He had had his own flashlight with him and had not had to turn up the
lights in the dormitory, a proceeding that might have caused attention,
and he was sure that no one had seen him at work, and indeed no one had.

When the boys went up to bed, Jack, still occupying the same dormitory
as at first, Billy was ready to see the result of his little joke, but
said nothing to any of the boys about it.

"Will you change beds with me to-night,