BULLETIN No. 220. 



APRIL, 1907. 



Meteorological Observations 



AT THE 



MASSACHUSETTS 



AGRICULTURAL EXPERIMENT 



STATION. 



Latitude, 42° 23' 48.5" N. Longitude 72° 31' 10" W. 



Height of barometer above ground, 51 ft- Above sea level, 2yj.^ ft. 

 Height of Wind Instruments 72 ft. 



MONTHLY SUMMARY. 



freasure. In inches. 



Maximum reduced to freezing, 30.11, 27th, 8 p. 

 Minimum reduced to freezing, 2S.68, 9th, 12 p. 

 Reducedt maximum reading, 30.41, 27th, 8 p. 

 Keducedt minimum reading, . 28.29, 9th 12 P. 



Mean semi-daily reduced, 29.885 



Monthly range, ■ 1.42 



*Air Temperature. In Degrees Fahr. 



Highest '/0.5,30th, 3 P. 



Lowest, 20.5. 3d, 6 A. 



Mean hourly, 41.5 



Mean of means of max. and min 41.7 



Mean sensible (wet bulb), 37.1 



Montlily range 49-0 



Highest mean daily 60.5,30th 



Lowest mean daily, 31.5,9th 



Mean maximum, 52.1 



Mean minimum, 31.4 



Mean daily range, 20.7 



Greatest daily range, 39.0, 4th 



Least daily range, 6.0,8th, 9th 



' Hntniditi/. 



Mean dew point 32.0 



Mean force of vapor 261 



Mean relative humidity, 74.1 



Hrecipitation. In inches. 



Total precipitation, 1.98 



Number of days on which .01 inch or more 



rain or melted snow fell, 8 



Total snow in inches, 8 



• Temperature in ground slielter. 

 t Keduced to freezing and sea-level. 



Wind. 



Total movement, 7096 ni. 



Greatest daily movement, . . . .433 m., 6th 



Least daily movement 59ni., 12th 



Mean daily movement, 236 m. 



Mean hourly velocity, 98 m. 



Maximum pressure per square foot, 12.0 lbs.= 

 49 m. per hour, 24th, 4 p., N. 



Maximum velocity for 5 minutes, 36 m. per 

 hour 24th, 4 p., N. 



Prevailing Direction, Northwest. 



Summary. 



North 17 percent. 



North northwest, 17 " " 



Southwest, 17 " " 



West northwest, 17 " " 



Other directions, 32 " " 



Weather. 



Mean cloudiness observed 53per cent. 



Total cloudiness recorded by the Sun 'J'h'er- 

 mometer. . . i34hrs.=34 per cent. 



Number of clear days, 12 



Number of fair days u 



Number of cloudy days, 7 



Itriffht Sunshine. 



Number of hours recorded, . . 268 lirs.=66< 

 Bom, 5th. 8th, i6th, 19th, 23d, 24tii, 26th, 



2Sth, 29th, 30th. 

 Snow, Sth.9th, loth, 19th, 20th. 

 u«<e», 35 miles or more per hour, 35 m. 2d, 



N.N.J!..; 42 m. 6th, N.N.W.; 44m. 20th, 



N.W. ; 35 m. 21st, N.W. 40 m. 22d, W.: 



49m. 24th, N. 



