Secret of the River by Fred M. White

It was a dark, moonless night, when, on the following evening, Nevil set out upon his journey to Ashdown Croft. The frost had gone and the earth was soft and yielding beneath his feet as he made his way silently up the drive in the direction of the house. A church clock somewhere near was striking the hour of eight, as Nevil reached the terrace in front of the Croft and then proceeded, cautiously, in the direction of the main quadrangle on to which the great library window looked out. He would have some time to wait yet, because he had learnt from Jakes that the usual dinner hour was half past seven, so that it would be another hour, at least, before the party adjourned from the dining-room into the library.

There was not a soul in sight and not a sound to be heard as Nevil felt his way to the library window and, after fumbling there a few moments, found the piece of stout string which Jakes had placed there for his use. A vigorous tug, and the casement opened an inch or two, after which the rest was easy. A moment later Nevil was inside the library and standing behind the thick velvet curtains that covered the window, so that he could close the casement behind him silently and without letting more than a puff of draught into the room.