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Members
Join Date: Oct 2009
Posts: 30
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No Alum, no party.
Dear all, Every Turkoteker must be acutely
aware that without Alum, his beloved rug collection would feature mostly
pieces like the one below, said with all due respect for Berber tribes and
brown sheeps.  I would like to share with you
Adam Hart-Davis’ wonderful story of how the wool dyeing industry of
Tudor’s England was saved from bankrupcy. (Mr. Hart-Davis is a British
scientist, author and broadcaster. His well researched and ironic series
have delighted Britons for 40 years.) Taking the Piss-Urine
Through the Ages. By Adam Hart-Davis.In the olden days,
words and expressions for urine seemed to be a common part of the
language: there is a place called Wyre Piddle in Worcestershire, and Lant
Street in South London (lant means stale urine), while in Dorset the River
Piddle flows through Piddletrenthide and Piddlehinton to Puddletown.
Today, however, urine is for some reason unmentionable in polite
conversation, but that does not prevent it from being interesting
stuff.Human urine contains a chemical called urea, which
slowly decomposes to make ammonia, often used as a household cleaning
agent, especially for glass. Ammonia has various useful properties and was
difficult to make before Victorian times; so urine was valuable. Poor
people could sell a bucket of urine for a penny, or half as much again for
redheads. The Roman emperor Vespasian put a tax on the stuff, and
centuries later the pissoirs in Paris were called vespasiennes in his
honour.Urine was used for stiffening the skirts of Roman
soldiers, for preparing raw wool, as a lubricant for wire-drawing, and in
the first gas masks, but perhaps its most spectacular historical use was
in the alum industry that grew up on the coast of North Yorkshire in the
early 1600s.A profitable industry: In Tudor times most
clothes were made from wool, and coloured with natural dyes. The colours
were brighter and longer-lasting if the dyeing was done with a mordant, a
chemical that locks the dyestuff to the fibres of the wool. The best
mordant was alum, and all Europe's alum came from the Tolfa hills, near
Rome—until Henry VIII had a row with the pope because he wanted to divorce
Catherine of Aragon, and the Vatican cut off our supply of
alum.So the hunt was on for alum in Britain. They tried
Alum Chine in Dorset and Alum Bay on the Isle of Wight, to no avail. And
then one Thomas Challoner discovered a way to make it. His recipe was to
dig the grey shale from the cliffs on the North Yorkshire coast, roast it
for nine months over a slow fire, and wash the ashes with water. Then add
buckets of stale urine and warm the mixture, to evaporate the water, until
a fresh chicken's egg just floats to the surface, showing that the
concentration is right. When the mixture is allowed to cool, beautiful
crystals of alum form in the container.At first the urine
was collected locally, and then from Newcastle and Hull, but demand grew,
and eventually it was brought from London, where buckets were left on
street corners, inviting men to contribute. Every week a horse came round
carrying barrels to collect the stuff—like a milk round in reverse —and
the barrels of decomposing urine were taken to the docks and shipped up
the North Sea to Whitby. The story goes that the skippers of these ships,
embarrassed about their cargo, would claim they were carrying wine.
"Rubbish! You're taking the piss..."In spite of this, carrying
urine one way and alum the other was good business for the ship owners.
Vast quantities of urine were needed: in November and December 1612,
16,000 gallons of "country urine" and 13,000 gallons of "London urine"
were taken from Whitby to the alum works at Sandsend, a couple of miles
north. Whitby mariner Luke Fox is documented as having carried 23 tonnes
of urine to Whitby, and returned to London with 29 tonnes of
alum.Astonishingly this alum production business, Britain's
first chemical industry, employed hundreds of men for 250 years, until
synthetic dyes were invented in the 1850s, and you can still see the huge
quarries hacked from the cliffs for 15 miles either side of
Whitby.What amazes me is how anyone worked out the process,
hundreds of years before any real chemistry was understood. Can you
imagine someone saying "There's a nice bit of grey rock. Let's roast it
for nine months and piss on it and see what happens." |