The thing that was seen running away was a boy--those footprints were made by a boy.

I have seen so many thousands on the sands here that I could swear to it.

He was attracted to the house from the road, which was quite near, by catching sight of something unusual through the blind; the brief says there were no curtains or shutters.

Now look at the photographs of the footprints.
See in No.

1, found outside the window, the toes are pressed down deeply into the mud.