Lightning-conductors, the discovery of 17–24 ———— early experiments with 25, 33 ———— the clergy on 26 ———— Professor Winthrop’s defence of 26, 27 ———— E. Kinnersley’s lectures on 27 ———— ‘Poor Richard’s Almanac’ on 28 ———— the gradual spread of 34–48 ———— Abbé Nollet’s animadversions on 35, 37 ———— Franklin’s reply thereto 36, 37 ———— their general use in North America 38 ———— their first erection on St. Paul’s 39 ———— their progress in Germany 43 ———— Italy 44 ———— the various metals used for 50 ———— Arago on the efficiency of 73 ———— the French ‘Instruction’ on 75 ———— Professor Pouillet on 78 ———— for ships 85 ———— Sir William Watson’s system of, for ships 87 ———— Sir William Snow Harris’s system of, for ships 90 ———— F. McTaggart’s opinion of 92 ———— their use in India 92 ———— the best material for 100–110 ———— German and French technical terms for 102 ———— and weathercocks 121 ———— Jarriant’s form of 133 ———— the twofold function of 142 ———— the insulation of 147, 160, 176 ———— Newall’s system of 140–168 ———— should they be carried down inside or outside the building 158 ———— Professor Clerk Maxwell’s theory of 164 ———— the necessity for periodically inspecting 218 ———— Dr. W. Holtz on the construction and maintenance of 223 ‘Lightning-rod men,’ the tramping, of America 133 Lightning and thunderstorms, character of 62 ———— protection, inquiries into 73–84 Line of least resistance, the 142, 148 Lisle (M. de) on the height of lightning-clouds 67 Louis XV. and experiments in electricity 6, 19