x table of contents. 



Table Page 



24 Minutes and seconds into decimals of an hour 57 



25 Local mean time at apparent noon 57 



26 Sidereal time into mean solar time 58 



27 Mean solar time into sidereal time 58 



CONVERSION OF MEASURES OF WEIGHT. 



28 Conversion of avoirdupois pounds and ounces into kilograms . . 60 



29 Conversion of kilograms into avoirdupois pounds and ounces . . 61 



30 Conversion of grains into grams 61 



31 Conversion of grams into grains 62 



WIND TABLES. 



32 Synoptic conversion of velocities 64 



33 Miles per hour into feet per second 65 



34 Feet per second into miles per hour 65 



35 Meters per second into miles per hour 66 



36 Miles per hour into meters per second 67 



37 Meters per second into kilometers per hour 68 



38 Kilometers per hour into meters per second 69 



39 Scale of velocity equivalents of the so-called Beaufort scale of 



wind 70 



Radius of critical curvature and velocities of gradient winds for 

 frictionless motion in highs and lows — 



40 English measures 71 



41 Metric measures 72 



REDUCTION OF TEMPERATURE TO SEA LEVEL. 



42 English measures 76 



43 Metric measures y'j 



REDUCTION OF BAROMETER READINGS TO STANDARD UNITS. 



Reduction of the barometer to standard temperature — 



44 English measures 80 



45 Metric measures 100 



Reduction of the mercurial column to standard temperature. 



(For U-shaped manometers with brass scales.) — 



46 English measures 123 



47 Metric measures 125 



Reduction of mercurial barometer to standard gravity — 



48 Direct reduction from local to standard gravity 127 



Reduction through variation with latitude — 



49 English measures 128 



50 Metric measures ■ 130 



