From Divination: A Conspiracy of Blood:
“Dee spent the next twenty minutes conducting his own examination of the room, looking for anything the previous searchers might have overlooked. He checked for loose panels, examined the underside of furniture, and even inspected the stone surround of the small fireplace for hidden cavities.
Nothing.
Frustrated, he sank onto the edge of the ruined bed, careful to avoid the spot where Kopernik’s body had lain.
I was a fool to think I might find something that had eluded a professional searcher, he thought. If Kopernik had anything useful hidden in this room, it is likely long gone now.
As he shifted his position, Dee’s shoe felt sticky against the floor.
Ugh.
He realised it was resting in a dark puddle, spilled ink from an overturned bottle on the floor beside the bed. With a grimace, he stood and reached for a nearby cloth, wetting it from the washbasin to clean the stain.
As he wiped up the ink, he noticed something else.
Beneath the fresh spill was another, older stain, one that had dried to a dull black.
Dee stared at it; a flash of insight forming in his mind.
Before he could pursue the thought further, the sound of footsteps on the stairs jolted him from his reverie. Someone was coming, another nighttime visitor with an interest in the dead astronomer’s belongings.
Quickly, Dee extinguished his candle and cast about for a hiding place. The room offered few options, so in the end, he positioned himself behind the door, hoping that whoever entered would not close it fully.”