1-81 Table 1-24.—Conversion Chart—Continued   To Convert To Multiply By Conversely,   Multiply By Feet Centimeters 30.48 3.281 10^-2 Feet Varas 0.3594 2.782 Feet of water at  4º C Inches of mercury at 0º C 0.8826 1.133 Feet of water at  4º C Kilograms per sq meter 304.8 3.281 10^-3 Feet  of water at 4º C Pounds per sq foot 62.43 1.602 10^-2 Foot-pounds Horsepower-hours 5.050 10 ^–7 1.98 10^-6 Foot-pounds Kilogram-meters 0.1383 7.233 Foot-pounds Kilowatt-hours 3.766 10^-7 2.655 10⁶ Gallons Cubic meters 3.785 10^-8 264.2 Gallons (liquid US) Gallons (liquid Br Imp) 0.8327 1.201 Gausses Lines per sq inch 6.452 0.1550 Gilberts per cm Oersteds 1 1 Grains (for humidity calculations) Pounds  (avoirdupois) 1.429 10^-4 7000 Grams Dynes 980.7 1.020 10^-3 Grams Grains 15.43 6.481 10^-2 Grams Ounces  (avoirdupois) 3.527 10^-2 28.35 Grams Poundals 7.093 10^-2 14.10 Grams per cm Pounds  per inch 5.600 10^–3 178.6 Grams  per cu cm Pounds per cu in 3.613 10^-3 27.68 Grams per sq cm Pounds per sq ft 2.0481 0.4883 Hectares Acres 2.471 0.4047 Henrys Microhenrys 1,000,000 0.000,001 Henrys Millihenrys 1000 0.001 Henrys per meter Gausses per Oersted 7.958 10⁵ 1.257 10^–6 Horsepower (boiler) BTU per hour 3.347 10⁴ 2.986 10^-5 Horsepower  (metric) (542.5 ft-lb per sec) BTU per minute 41.83 2.390 10^-2 Horsepower  (metric) (542.5 ft-lb per sec) Ft-lb per minute 3.255 10⁴ 3.072 10^-5 Horsepower  (metric) (542.5 ft-lb per sec) Kilogram-calories               per min 10.54 9.485   10^-2 Horsepower                    (550 ft-lb per sec) BTU  per minute 42.41 2.357 10^-2 Horsepower                     (550 ft-lb per sec) Ft-lb per minute 3.3 10⁴ 3.030 10^-5 Horsepower                     (550 ft-lb per sec) Kilowatts 0.745 1.342 Horsepower                    (550  ft-lb per sec) Watts 746 1.342 10^-3 Horsepower  (metric) (542.5 ft-lb per sec) Horsepower                    (550 ft-lb per sec) 0.9863 1.014 Horsepower                    (550 ft-lb per sec) Kilogram-calories  per min     10.69 9.355 10^-2