e and a couple of chairs, and a large cupboard
which occupied the whole of one side of the wall of the house
against which the shed was built. In a corner of the shed stood a
very good-looking Douglas motor-cycle, and on a nail on the wall
hung a set of motor-cyclist's overalls. A few petrol cans, some
full, some empty, stood against the wall.

Desmond examined the machine. It was in excellent condition,
beautifully clean, the tank half full of spirits. A little dry
sand on the tires showed that it had been used fairly recently.

"Old man Bellward's motor-bike that he goes to the station on,"
Desmond noted mentally. "But what's in the big cupboard, I
wonder? Tools, I expect!"

Then he caught sight of a deep drawer in the table. It was
half-open and he saw that it contained various tools and spare
parts, neatly arranged, each one in its appointed place.

He went over to the cupboard and tried it. It was locked. Desmond
had little respect for Mr. Bellward's property so he went over to
the tool drawer and selected a stout chisel with which to burst
the lock of the cupboard. But the cupboard was of oak, very
solidly built, and he tried in vain to get a purchase for his
implement. He leant his left hand against the edge of the
cupboard whilst with his right he jabbed valiantly with the
chisel.

Then an extraordinary thing happened. The whole cupboard
noiselessly swung outwards while Desmond, falling forward, caught
his forehead a resounding bang against the edge of the recess in
which it moved. He picked himself up in a very savage frame of
mind--a severe blow on the head is not the ideal cure for
hypochondria--but the flow of objurgatives froze on his lips. For
he found himself looking into Mr. Bellward's library.

He stepped into the room to see how the cupboard looked from the
other side. He found that a whole section of bookshelves had
swung back with the cupboard, in other words that the cupboard in
the toolshed and the section of bookshelves were apparently all
of one piece.

He carefully examined the walls on either side of the recess in
the library to see how the mechanism worked. The bookshelves were
open, made of mahogany, the sides elaborately carved with leaves
and flowers. Desmond ran his hand down the perpendicular section
immediately on the right of the recess. About halfway down--to be
exact, it was in line with the fifth shelf from the floor--his
fingers encountered a little knob which gave under