Part 128

=Arrow=, what causes it to fly? 408

=At= what point does water boil? 220

=At= what rate does thought travel? 242

=Australian Ballot=, where first used, 122

=Automobile= (illus.), axle, location of, 186 beginning of, 183 carburetor, location of, 184 carburetor, use of, 184 chassis, complete, 188 cog-wheels, use of, 183 cog-wheels, location of (illus.), 183 crankcase, location of (illus.), 183 cylinder, location of (illus.), 184 drive shaft, location of (illus.), 187 electric generator, use of, 185 exhaust, 184 fenders, location of, 188 fenders, use of, 188 finished car (illus.), 189 first American (illus.), 189 fly-wheel, location of (illus.), 183 fly-wheel, use of, 183 frame (illus.), 186 gasoline, what it does, 183 gasoline tank, location of, 187 gears, location of (illus.), 183 gears, use of, 183 heart of (illus.), 184 how improved, 190 magneto, location of, 185 magneto, use of, 185 marvellous growth of twenty years, 189 modern power plant complete, 190 oil pan, use of, 184 oil pump, location of, 184 piston, location of (illus.), 183 piston, use of, 183 power plant, an (illus.), 185 radiator, location of (illus.), 188 radiator, use of, 188 ready for the wheels, 187 second stage of construction (illus.), 186 self-starter, location of, 185 self starter, use of, 185 Smithsonian exhibit of complete power plant, 190 springs, location of (illus.), 186 springs, use of, 186 steering gear, location of (illus.), 187 street scene 20 years ago, 189 transmission, location of, 186 tire pump, use of, 185 tires, how made, 382 transmission, use of, 186 water pump, location of, 185 water pump, use of, 185 what the completed chassis looks like (illus.), 188

=Bacon, Roger=, discoverer of gunpowder, 44

=Balance=, effect of sunlight on, 37

=Baldness=, chief course of, 143 why some people are, 143

=Ball=, why it bounces, 63 bearings, what they are, 180

=Balloon=, what keeps it up, 199 why it goes up, 199

=Ballot=, when first used, 122 Australian, where first used, 122

=Bearings, Ball=, what they are, 180

=Bee=, how it lives, 336 why it has a sting, 336

=Bell, Alexander Graham= (illus.), 70 first telephone, 72

=Bend=, why things, 62

=Biplanes=, Curtiss (illus.), 131 in flight, Curtiss (illus.), 136

=Birds=, how do they find the old home? 408 how they learn to fly, 178 how they find their way, 407 reproduction of life in, 179 why do they sing? 408

=Birds’ Eggs=, why different colors, 233

=Blasting= gelatin, definition of, 206

=Bleriot, M.=, first European flights, 129

=Blotter=, capillary attraction of, 18 how it takes up ink, 18

=Blush=, why do we, 194

=Boat=, how it can sail under water, 269 hydroplane of submarine, 270 inside of a submarine (illus.), 272

=Bodies=, swiftest moving, 25

=Boiling= point of water, 220 what makes water, 220

=Boring mill= (illus.), 56

=Bottles=, gurgle in, 63

=Bounce=, why a ball will, 63