1.Weapons and implements. 2.The cñassical period. 3.The medieval and early moder period. 4.The school of galileo. 5.The school of newton. 6.The acoustics of the ancients. 7.Acoustics in the western cycle of culture. 8.The nineteenth century and after. 9.Through ancient eyes. 10.Optics in the classical cycle. 11.“Westward Ho”. 12.The school of newton and Huygens. 13.The school pf young and Fresnel. 14.Fingers before thermometers. 15.The fruits of the thermometer. 16.Amber and the magnet. 17.Poles and charges. 18.Conduction. 19.Influence and charges. 20.Conduction. 21.Influence or induction charges. 22.Electric current. 23.Induced currents. 24.Electro-magnetic waves and cathode rays. 25.The electron theory.