Measures and weights

1) Linear measures

1 inch (in) = 2.54 cm
1 foot (ft) = 12 inches = 30.48 cm
1 yard (yd) = 3 feet = 91.44 cm
1 furlong (fur) = 220 yards = 201.17 m
1 mile (mi) = 1760 yards = 1609.344 m
1 league (lea) = 3 miles = 4828.032 m

2) Nautical measures

1 fathom = 6 feet = 1.829 m
1 cable = 608 feet = 185.31 m
1 nautical, sea mile = 10 cables = 1.852 km
1 sea league = 3 nautical miles = 5.550 km

3) Liquid measures of capacity (BRITISH)

1 gill = 0.142 l
1 pint (pt) = 4 gills = 0.568 l
1 quart (qt) = 2 pints = 1.136 l
1 gallon (gal) = 4 quarts = 4.564 l
1 barrel = 35 gallons = 159.106 l
1 barrel = 36 gallons (Bier) = 163.656 l

4) Liquid measures of capacity (American)

1 gill 0.118 l
1 pint = 4 gills = 0.473 l
1 quart = 2 pints = 0.946 l
1 gallon = 4 quarts = 3.785 l
1 barrel = 42 gallons = 159.106 l

5) Avoirdupois weights

1 grain (gr) = 0.065 g
1 dram (dr) = 27.3438 grains = 1.772 g
1 ounce (oz) = 16 drams = 28.35 g
1 pound (lb) = 16 ounces = 453.59 g
1 stone = 14 pounds = 6.348 kg
1 quarter = 28 pounds = 12.701 kg
1 hundredweight (cwt) = 112 pounds (Brit) = 50.8 kg = 100 pounds (US) = 45.36 kg
1 ton = 20 cwt (Brit) = 1016 kg = 2000 pounds (US) = 907.185 kg

6) Temperature conversion

Fahrenheit > Celsius subtract 32 and multiply by 5/9		Celsius > Fahrenheit multiply by 9/5 and add 32
°F	°C	°C	°F
0	-17.8	0	32
50	10	30	86
100	37.7	50	122
200	93.3	100	212

Thanks to Klaus.