Barometer World is the world's foremost
seller and repairer of antique and modern mechanisms
for determining atmospheric air pressure.
A museum attached to a shoppe features examples of such arcane and wonderful
instruments as the Tempest Prognosticator.
Also known as the 'Leech Barometer' or the
Atmospheric Electromagnetic Telegraph,
the prognosticator was a 19th-century weather forecasting
device that was first exhibited at the
Great Exhibition in London in 1851.
A contemporary account of the invention described it as an
elaborate and highly ornate apparatus...evolved by a certain Dr. Merryweather
who had observed that during the period before the onset of a severe storm,
fresh water leaches tended to become particularly agitated.
The learned Doctor decided to harness the physical energy of these
aquatic bloodsuckers to operate an early warning system.
On the circular base of his apparatus -he installed glass jars, in which
a leech was inside and attached to a fine chain that led up to a miniature belfry-
from whence that tinkling tocsin would be sounded on the approach of the tempest.
The more the bells that rang, the greater the likelihood of an impending storm.
[A full scale model is to be seen at the Barometer World and Museum
at the Quicksilver Barn, Merton
Okehampton, Devon, EX203ds]