Regarding the hiding of a trap door. I have seen a large
irregularly built trap door of about 3 x 5 feet in the
flooring in a house in Virginia outside near Purcellville.
The door covered a space large enough to hide several
people at once. It was used to help hide slaves who were
excaping via the underground railroad. The door was made of
variable width boards, of variable lengths, that
interdigitated perfectly with the boards of the rest of the
floor. So perfectly fitted it was, that one could stand
directly on the door and inspect it for any
signs of irregularities and the door and and not see it.
rough illustration of trap door
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