1620 Dutch-born Cornelius Drebbel tests submarine, cruises 15 feet under Thames. Germany's Gottfried Wilhelm Leibniz devises mechanical calculator to add, subtract, divide and multiply. Paris prints first directory of street addresses to aid firefighters. Jethro Tull creates horse-drawn mechanical drill to plant seeds in rows. Britain passes first copyright act.
Umbrellas become popular in London.
1730 German A. Ketterer invents cuckoo clock. Anders Berch becomes first professor of economics, in Uppsala, Sweden. 1743 First known elevator installed, at Versailles for Louis XV to see his mistress. 1759 Dr. Samuel Johnson denounces advertisements as overexaggerated and false. Belgian creates roller skates by replacing blades of ice skates with wheels.