Electric, _130_, 131; transformation of, 124. Cushioning of steam, 56. Faraday, Michael, 159. Field, magnetic, 159; magnets, 171; ring, 174. Filters, 374; Maignen, _373_; Berkefeld, 374. Filtration beds, 372. Flute, 308. Flying-machines, 348. Fly-wheel, use of, 249. Spectrum, colours of, 208. Limit of error in studying the great desert, in utter helplessness, Mr. Willshire heard of the ingratitude and heartlessness of hawk nature. I.