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
A Certain Magical Index the first volume of "A Certain Magical Index", according to editor Kazuma Miki, "(to be blunt) it sold like crazy. Shortly after the official release date, we had to do a reprint half the size of the original printing. It was on a Monday. I still remember it now. It was quite an achievement for an unknown newcomer". In May 2010, it was reported that "A Certain Magical Index" became Dengeki Bunko's No. 1 bestseller and it became the first Dengeki Bunko series to sell over 10 million copies. Later that year, it became the fifth best selling light novel