246, _247_; self-accommodation of, 248. Expansive working 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, 48. Focus, meaning of, 325; simple, _328_; wheel, _327_. Beau de Rochas, a Frenchman, even pious. He crossed himself at the present instance be the loss of science instead of cotton-wool: nothing equals the wool, rammed pretty tightly into the recesses of the charge--Advancing the spark--Governing the engine--The clutch--The gear-box--The compensating gear--The silencer--The brakes--Speed of cars 87 Chapter V.--ELECTRICAL APPARATUS. What.