One of my shells was misplaced for almost a year - well, not really misplaced
- I knew right where it was.  I just couldn't get at it.  I had a specimen of
Opisthostoma mirabile, a tiny, exquisite land snail from Borneo which has
more twists, frills, and spines than you would think possible on a 5 mm
shell.  Someone wanted to purchase it, but it was the only specimen I had
ever seen, from an old collection, so before I sent it off, I thought I would
take it in to work and make a super image of it using the scanning electron
microscope.  I put the shell carefully on the specimen holder, closed the
door to the chamber, and started the process of pumping down the chamber (an
electron microscope requires that the specimen be under high vacuum).  Once
the vacuum pumps had done their job, I turned on the electron beam, sat down
at the console (you do your viewing on a video monitor), and focused in on
the specimen holder.  And there it was - the specimen holder - No shell!  I
repressurized and opened the chamber, and searched every square inch of the
interior.  No shell.  So, I had to conclude that the shell had exited the
chamber through the only other opening - the aperture leading to the vacuum
pump!  When the pump sucked the air out of the chamber, it had sucked the
shell right along with it.  The vacuum pump is a sealed unit, filled with hot
(450 degrees F) oil.  So, I had to write the person who wanted the shell, and
tell him it had been eaten by a microscope.
But wait!  There's more!  The following spring we had a preventive
maintenance done on the microscope by an outside firm.  One of my co-workers
who was using one of our stereomicroscopes (an ordinary light microscope -
not electron), called me over and said "take a look at this".  I sat down,
peered into the eyepieces, and there before my eyes was my long-lost shell, a
bit oily but otherwise unscathed.  The workers had disassembled the vacuum
pump to replace the oil.  He had planned on screening the old oil to see if
he could find the shell, but it actually wasn't in the oil at all.  It had
landed on a steel rim about 1/4 inch wide, just above the hot oil, and sat
there for 10 months.  I put the shell in a solvent to rinse off the oil,
dried it, and it was good as new.  And it finally reached the customer who
wanted it.
Paul M.