Scale Vernier Unit Test Plate Ott's K.&E., No. 4230 Coradi's Compensating No. Ratio Linear Area Actual Relative Area Reading Setting Constant Setting Constant Setting Constant Setting Constant 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 No. mm mm mm mm Sq. mm Sq. mm Sq. mm Sq. mm Sq. mm Units ½ mm Units ½ mm Units ½ mm Units ½ mm Units 1 1:1 1 = 1 1 = 1 10. 10. 10000 1000 324.1 17305 29.4 18409 329.4 22641 _ _ _ _ _ _ _ _ 2 1:2 1 = 2 1 = 4 10. 40. 40000 1000 324.1 17305 29.4 18409 329.4 22641 _ _ _ _ _ _ _ _ 3 1:5 1 = 5 1 = 25 10. 250. 250000 1000 324.1 17305 29.4 18409 329.4 22641 _ _ _ _ _ _ _ _ 4 1:10 1 = 10 1 = 100 10. 1000. 1000000 1000 324.1 17305 29.4 18409 329.4 22641 _ _ _ _ _ _ _ _ No. m : m mm mm Sq. mm Sq. mm Sq. mm Sq. m Sq. m Units ½ mm Units ½ mm Units ½ mm Units ½ mm Units 5 1:20 1 = 20 1 = 400 10. 4. 4. 1000 324.1 17305 29.4 18409 329.4 22641 _ _ _ _ _ _ _ _ 6 1:25 1 = 25 1 = 625 8. 5. 6.25 1250 264.0 17899 94.8 18317 263.5 23736 _ _ _ _ _ _ _ _ 7 1:50 1 = 50 1 = 2500 10. 25. 25. 1000 324.1 17305 29.4 18409 329.4 22641 _ _ _ _ _ _ _ _ No. m : m mm mm Sq. mm Sq. m Sq. mm Sq. m Sq. m Units ½ mm Units ½ mm Units ½ mm Units ½ mm Units 8 1:100 1 = 100 1 = .01 10. .1 100 1000 324.1 17305 29.4 18409 329.4 22641 _ _ _ _ _ _ _ _ 9 1:250 1 = 250 1 = .0625 8. .5 625 1250 264.0 17899 94.8 18317 263.5 23736 _ _ _ _ _ _ _ _ 10 1:500 1 = 500 1 = .25 10. 2.5 2500 1000 324.1 17305 29.4 18409 329.4 22641 _ _ _ _ _ _ _ _ No. m : m m Sq. m Sq. mm Sq. m Sq. m Units ½ mm Units ½ mm Units ½ mm Units ½ mm Units 11 1:1000 1 =   1.0 1 =     1.0 10.0 10.0 10000 1000 324.1 17305 29.4 18409 329.4 22641 _ _ _ _ _ _ _ _ 12 1:1250 1 =   1.25 1 =     1.5625 6.4 10.0 15625 1562.5 216.3 19299 146.9 18317 210.8 25885 _ _ _ _ _ _ _ _ 13 1:2500 1 =   2.5 1 =     6.25 8.0 50.0 62500 1250 264.0 17899 94.8 18317 263.5 23736 _ _ _ _ _ _ _ _ 14 1:4000 1 =   4.0 1 =   16.0 6.25 100.0 160000 1600 211.8 19495 151.9 19832 205.9 26185 _ _ _ _ _ _ _ _ 15 1:5000 1 =   5.0 1 =   25.0 8.0 200.0 250000 1250 264.0 17899 94.8 18317 263.5 23736 _ _ _ _ _ _ _ _ 16 1:10000 1 = 10.0 1 = 100.0 10.0 1000.0 1000000 1000 324.1 17305 29.4 18409 329.4 22641 _ _ _ _ _ _ _ _ 17 1:20000 1 = 20.0 1 = 400.0 10.0 4000.0 4000000 1000 324.1 17305 29.4 18409 329.4 22641 _ _ _ _ _ _ _ _ 18 1:360 1 =     .36 1 =       .1296 7.712 1.0 1295 1296 255.6 18075 104.0 18480 254.2 24019 _ _ _ _ _ _ _ _ 19 1:480 1 =     .48 1 =       .2304 8.68 2.0 2304 1152 284.6 17602 72.5 18546 285.9 23215 _ _ _ _ _ _ _ _ 20 1:1200 1 =   1.20 1 =     1.44 6.944 10.0 14400 1440 232.4 18686 129.2 18929 228.7 24982 _ _ _ _ _ _ _ _