The private boxes have electronic locks that log every opening with the key's number, and every key is issued to a named holder. Box 47 has no holder, its two keys are in the safe, and it is opened every night at ten past one by a key number that was never cut, and the mail I put in it for the test is gone by morning.
I am the box section supervisor, and the lock logs are on my desk every morning.
How the boxes work.
Each box has a lock that reads a coded key and logs the key's number and the time of every opening. Keys are cut against the number and issued to the box holder, two per box, and the numbers of all keys in existence are on my register.
An unrented box has its keys in the safe and no openings.
Box 47 is unrented. It has been since the holder gave it up in 2004, and it is not let, because it is at the bottom of the wall and awkward, and its keys are in the safe.
Its lock logs an opening every night at ten past one. The key number logged is in the format of our keys and is not on my register, and the register goes back to when the locks went in.
The box is in the customer hall, which is locked and alarmed at night, and its door is on the camera that covers the wall.
The camera shows the door of 47 open. On its own, at ten past one, the way it opens when a key is turned, and stay open the time it takes to take out mail, and close.
What has been checked.
The lock, replaced. The new lock logged the same key number on its first night.
The keys in the safe. Both there, both cut to 47, both logged when I test them, with their own numbers, which are not the night number.
The box. Empty, because nothing is addressed to it. So I addressed something to it: a plain envelope, my own hand, put in the box by me at five, with the door locked and the camera on it.
In the morning the box was empty, the log showed the night opening, and the camera showed the door open and close with the envelope inside going from there to not there in the time the door was open, and nobody at the wall.
Where the envelope went.
I had put a card in it with my name and the office's address, on the principle that mail finds its way back.
It came back. Through the post, four days later, franked at an office in a city two hundred miles away, addressed to me, in my own hand, with the card inside, and on the back of the card, in a hand that was not mine, one word, which was received.
The last holder.
Box 47 was rented for thirty years by one man, who gave it up in 2004 because, the note on the file says, he would no longer be able to collect. He is not, as far as I can find, alive. His address on the file is a house that has been three flats since 2010.
What is done about it.
The night opening is on the log and the audit flags an unregistered key number, and the audit has been told, in writing, that the number is a legacy artefact, which is what the lock supplier called it, and the audit has stopped asking.
Box 47 is not let. I have taken it off the list.
What I do.
I read the logs.
The one thing I have changed is that I put something in box 47 on a Friday.
Not every night. Once a week, a plain card, no message, in my hand, put in at five, and in the morning it is gone, and it does not come back through the post any more, and on Monday mornings the log shows the night opening on Friday and no other, as though a box that has something in it is a box worth opening once.
I started that after the second time I put an envelope in, when it came back, from the same city, in my hand, and the word on the card was still.