Linear:
Inch                                     2.54 cm
Foot               12 In                 30.48 cm
Yard                3 Ft                 0.91 m
Rod                16.5 ft.              5.03 m
Furlong            40 Rods             201.17 m
Mile             5280 Ft. 8 Furlongs  1609.30 m 
League              3 Miles

Chain (Engineers)  100: 1 ft links      30.48 m
Chain (surveyors)  100: 7.92" links     20.12 m
                   1/10 furlong 
                   1/80 mile


                 Area
Acre              640 acres/sq.Mi.
Section      	  1 sq.mile, or 640 acres.
Township          36 square miles




                     Metric
mm Millimetre			25.4 mm/in	                
cm Centimetre	10 mm   	2.54 cm/in
dm Decimetre	100 mm  	3.05 dm/ft
m  Metre	1000 mm         39.37 in/m
Dm Decameter    10 m            

Are             100 sq.m      119.6   sq.yards     10m/side
Hectare         100 ares        2.47  acres       100m/side
Hectometer      1 sq.km.	0.386 sq.miles   1000m/side