BULLETIN No. 283. 



JULY, 1912 



Meteorological Observations 



AT THE 



MASSACHUSETTS 



AGRICULTURAL EXPERIMENT 



STATION. 



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



Height of haro meter above ground. Si ft. Above sea level, 2yj.s ft. 

 Height of Wind Instniinents 72 ft. 



MONTHLY SUMMARY. 



i'ressure. In inches. 



Ma.Kinimn reduced to freezing, 3006, 2d, 7 A. 

 Miiiiinuin reduced to freezing, 29.18, 29th, 4 p. 

 Reduced! maximuui leading, 30.35, 2d, 7 A. 

 Reducedt minimum reading, 29.46, 29th, 4 p. 



Mean semi-daily reduced, 29.980 



Montlily range 0.S9 



*.\ir Temperature. In Degrees Falir. 



Highest, 9S.5, 8th, 3:30 P.; 9th, 2 p. 



Lowest 41.0. ist, 4:30 A. 



Mean hourly, 71-6 



Mean of means of max. and min 71.9 



Mean sensible (wet bulb), 64 i 



Monthly range 57'5 



Highest mean daily, .... 81.6, Sth, 9th, loth 



Lowest mean daily 61. S, 23d 



Mean maximum, S4.6 



Mean minimum, 59-2 



Mean daily range, 25.4 



Greatest daily range, 4i-o. 'st 



Least daily range, 6-0, 18th 



Humidity. 



Mean dew point, 60.5 



Mean force of vapor, 762 



Mean relative humidity, 7i-5 



Precipitation. In inches. 



Total precipitation, 2.61 



Number of days on which .01 inch or more 

 rain fell • 7 



♦Temperature in ground shelter, 

 t Reduced to freezing and sea-level. 



Wind. 



Total movement 3992m. 



Greatest daily movement, .... 246ni., 23d 



Least daily movement, 39n)., 1st 



Mean daily movement, 129 m 



Mean hourly velocity, 5-4 m 



Maximum pressure per square foot, 5.5 lbs.:= 



33m. per hour, 9th, 7 p., W.N.W. 

 Maximum velocity for 5 minutes, 21 m. per 



hour, 5th, 4P., S. 

 Prevaihng Direction, Southwest. 



Summary. 



South 26 per cent 



South Southwest 23 " " 



North 19 " " 



Other directions 32 " " 



Weather. 



Mean cloudiness observed, . • . .46 per cent. 

 Total cloudiness recorded by the Sun Ther- 

 mometer, 202 hrs.=44 per cent. 



Number of clear days, 3 



Number of fair days, 21 



Number of cloudy days, 7 



Bright Sunshine. 



Number of hours recorded, . . 260 hrs.=565i 

 Rain, nth, 14th, i8th, 21st, 29th, 30th, 31st. 

 Thunder and Liglitning, nth, 14th. 

 Gales, 35 or more miles per hour : None. 



