Medieval technology that its potential was fully achieved. Artesian well (1126) A thin rod with a hard iron cutting edge is placed in the bore hole and repeatedly struck with a hammer, underground water pressure forces the water up the hole without pumping. Artesian wells are named after the town of Artois in France, where the first one was drilled by Carthusian monks in 1126. Central heating through underfloor channels (9th century) In the early medieval Alpine upland, a simpler central heating system where heat travelled through underfloor channels from the furnace room replaced the Roman hypocaust at some places. In Reichenau
What Is a Nation? and continues to be invoked. Political historian Karl Deutsch, in a quote sometimes mistakenly attributed to Renan, said that a nation is "a group of people united by a mistaken view about the past and a hatred of their neighbours". Benedict Anderson's 1983 work Imagined Communities, which states that a nation is an "imagined political community", argues that Renan contradicts himself when he says French people must have forgotten the St. Bartholomew's Day massacre, yet does not explain what it is. In other words, Renan assumes that all his readers will remember the very massacre he says they have forgotten.