In addition to their
medical use, the leech was also used in
Victorian times by
sailors, who used them to detect impending
storms.
A
contraption existed where twelve
leeches were placed in
bottles, with small plates attatched at the top which, when knocked slightly, would ring a
bell. The theory was that when a storm approached, the leeches would react to the change in
air pressure, and
instinctively attempt to seek cover by climbing out of the bottle. They would then knock the plate, ringing a bell.
The idea was eventually scrapped because of the fact that the leeches had to be fed periodically, and also because the
sailors were reluctant to place their
lives in the "hands" of a bunch of
parasites.