Pocketbook of Useful Formulæ and Memoranda
for Civil and Mechanical Engineers

303 OF ENGINEERING FORMULÆ. Tables for Reducing other Measures to the Metrical Measures of the Centimétre- GRAMME-SEGOND (C. Gr. S.) AND MÉTRE- GRAMME-SECOND, Oli ABSOLUTE SYSTEMS. By Paget Higgs. The relations of linear, superficial, and capacity measures are given elsewhere. Velocity:— 1 foot a second = 30 "4797 cm, or '3048 in. a second. 2 statute mile an hour = 44 • 704 cru. = '447 m. a second. 3 nautical mile or knot an hour = 51:453 cm. == 'öliö m. a second. 4 kilometre an hour = 27'777 cm. = -278 m. a second. Density:— Pure water at 4° C. = 1*000013 grm. a cub. cm. 5 lb. a cubic foot = '016019 „ ,, Force:— (9 = 981.) The C. G. S. unit of force is called the- dyne, and is the fore# which acting upon a gramme for a second, generates a velocity of a centimetre a second; or is the force which acting upon a gramme produces the C. G. S. unit of acceleration; or upon any mass for 1 second produces the C. G. S. unit of momentum. The M. G. 8. unit of force = 100 dynes.