Making violins is such a practical knowledge. Noone could make violins as Antonio Giacomo Stradivari. He lived from 1648 to 1737 and made the world-famous Stradivarius violins. The few instruments that are left after Stradivari (about 660 pieces) costs a fortune today. Ole Bull had such a violin that was built in 1687, and it is called Lady Blunt. It is amazing that it was sold in June 2011 for 88.600.000 Norwegian kroner (15.894.000 U.S. dollars). How did he learn to create such wonderful instruments? Not by reading a book about it. He was an apprenticed for 13 years with a violinmaker, the maestro Nicola Amati, in the years 1666 to 1679. Stradivari learned the craft on to his apprentices (including his two sons), but then the maestro/student tradition died away and today no one can make violins as Stradivari did.