Unlike so many other expressions, this one is well documented. It's a direct 
translation of the Spanish sangre azul. Many of the oldest and proudest 
families of Castile used to boast that they were pure bred, having no link with 
the Moors who had for so long controlled the country, or indeed any other 
group. As a mark of this, they pointed to their veins, which seemed bluer in 
colour than those of such foreigners. This was simply because the blue-tinted 
venous blood showed up more prominently in their lighter skin, but they took it 
to be a mark of their pure breeding. So the phrase blue blood came to refer to 
the blood which flowed in the veins of the oldest and most aristocratic 
families. The phrase was taken over into English in the 1830s.

Best Regards,
Arnold Beland

Sitting here looking at veins through my practically transparent skin.

www.abeland1.com
  ----- Original Message ----- 
  From: Matthew McCann 
  To: silver-list@eskimo.com 
  Sent: Sunday, October 17, 2004 4:18 PM
  Subject: CS>Antiquarian Epidemiology






  Hello, Members of the List,

  I work with people who serve periodically as missionaries in
  the Amazon basin where leprosy still occurs. They are not
  medical missionaries and have little or no contact with
  victims of Hansen's disease. Some have put a question to
  me about EIS, though.

  The term 'bluebloods' comes from the european nobles
  who escaped plagues such as the Black Death by using
  silver tableware. Did the bluebloods also escape leprosy?
  Some medieval people were keen enough observers to
  notice some relation between bubonic plague, rodents and
  a dearth of cats. Does anyone know if they noticed
  if silver drove away leprosy?

  Thanks in advance for your input.

  Matthew


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