jumped from a height on to grass, and then quick footsteps.

He waited breathless and rigid, expecting every moment to see a form
loom up beside him in the darkness. It was useless to run. His only
chance was to stay perfectly quiet.

Then it dawned upon him that the man was running away from him, not
towards him. His first impulse was to give chase, but prudence
restrained him. Catching burglars is an exhilarating sport, but it is
best to indulge in it when one is not on a burgling expedition oneself.

Besides he had come out to get his book, and business is business.

There was no time to be lost now, for someone might have heard one or
both of the noises and given the alarm.

Once the window was broken the rest was fairly easy, the only danger
being the pieces of glass. He took off his coat and flung it on to the
sill of the upper window. In a few seconds he was up himself without
injury. He found it a trifle hard to keep his balance, as there was
nothing to hold on to, but he managed it long enough to enable him to
thrust an arm through the gap and turn the handle. After this there was
a bolt to draw, which he managed without difficulty.

The window swung open. Jim jumped in, and groped his way round the room
till he found his book. The other window of the room was wide open. He
shut it for no definite reason, and noticed that a pane had been cut
out entire. The professional cracksman had done his work more neatly
than the amateur.