Leeches going down a storm
QUESTION How did Dr George Merryweather’s Tempest Prognosticator, a weather prediction device, work?
The Tempest Prognosticator was a stormprediction device powered by leeches.
Dr George Merryweather was a Whitby GP and part-time inventor. In 1832 he invented the Platina Lamp, to ‘keep burning for a fortnight on an economical mixture of pure alcohol and whisky, at a cost of one penny for eight hours’.
By 1850 he had turned to weather prediction, inventing the Atmospheric electromagnetic Telegraph conducted by Animal Instinct, better known as the Tempest Prognosticator. It was displayed at the Great exhibition of 1851.
As a doctor, Merryweather was familiar with leeches. The Victorians were fond of blood-letting, a treatment used to cure just about anything from haemorrhoids to fatigue.
Leeches were used in their thousands and apothecaries displayed their merchandise in ornate jars. During a shortage in London, leeches being shipped from India were described as ‘willing and even anxious to do their duty’.
This supposed animal intelligence and the elaborate storage methods inspired Merryweather. The Tempest Prognosticator consisted of a circle of 12 pint glass bottles, every one holding a live leech. each bottle was arranged beneath a hammer attached by wire to a piece of fine whalebone set loosely in the neck of the bottles. The apparatus was contained within a glass bell surrounded by an elaborate Indian temple design.
Changes in atmospheric pressure before a storm would drive the leeches to the neck of the bottle, where they would dislodge the whalebone and ring a bell.
Merryweather observed that the leeches lurched and tumbled ‘as if they were subjecting their bodies to some powerful, but imperceptible, influence’.
Twelve leeches were required because of their inconsistent nature. Merryweather found some to be ‘positively prophetic’ and others ‘absolutely stupid’. When several bells rang in succession, a storm had been ‘prognosticated’. Six versions of the Prognosticator were designed but sadly none is preserved, though there is a replica in Whitby Museum.
Its use on ships was investigated in 1854 by Robert FitzRoy, Meteorological Statist to the Board of Trade. he determined it to be impractical, as the leeches needed to be fed once a month and have their water changed every five days, never mind that it was highly unreliable.
FitzRoy preferred the storm glass — a vial containing a mixture of camphor, chemicals, water, alcohol and air. Crystals and cloudiness in the liquid were thought to indicate forthcoming changes to the weather. It turned out to be more useless than the Tempest Prognosticator. Keith Berriman, Mablethorpe, Lincs.
QUESTION What was the first item sold on eBay? BUY-AnD-SeLL website eBay was founded in 1995 by Pierre Omidyar in his spare bedroom. The first item listed was a laser pointer, which Omidyar had broken. To his surprise, it sold for $14.83, even though the buyer knew it didn’t work.
When eBay held a conference to celebrate its 20th birthday in 2015, Canadian Mark Fraser contacted the company to say he had bought the broken pointer and still had it. Today, eBay is one of the 50 most valuable brands in the world, with 187 million people using the site.
noteworthy items sold include clippings of Justin Bieber’s hair for £30,000, a half-eaten slice of French toast left by Justin Timberlake and a suit of armour for a guinea pig, both of which fetched more than £800. A student sold a single cornflake for £1.20 and a Gulfstream jet changed hands for almost £4 million.
Ian MacDonald, Billericay, Essex.
QUESTION La-Z-Boy built seats for tanks in World War II. Did other unexpected companies support the war effort?
MeRRYThOUGhT in Ironbridge, Shropshire, is a famous teddy bear maker. When World War II broke out, the Admiralty took over the factory for vital map-making work, forcing soft toy production to stop. The workforce also produced textile items such as chevrons, helmet linings, igniter bags, gas mask bags and hot water bottle covers.
Birmingham toy company Chad Valley made hospital beds, electrical coils and starters and barrels for anti-aircraft guns.
Mille Evans, Much Wenlock, Shropshire. One significant war effort was the construction of 710 halifax bombers by the London Passenger Transport Board (LPTB), aka London Transport.
Frederick handley Page’s company had built the prototype aircraft and a number of companies built sections of the plane, final construction of which took place at Leavesden Airfield, now home to Warner Bros Studio Tour London — The Making Of harry Potter.
The LPTB made parts at its Chiswick Works and raised larger sections at the hastily completed northern Line Underground Depot at Aldenham, herts.
Thanks to the combined effort of several companies, the first halifax took off from Leavesden on December 8, 1941.
The Aldenham factory would never see any Underground trains as the extension of the line from edgware was abandoned. The buildings became Aldenham Bus Overhaul Works, where Cliff Richard performed at the start of his 1963 film Summer holiday.
The works closed in 1986 and were demolished ten years later.
Tony Beard, Billericay, Essex.
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