BULLETIN No. 319. 



JULY, 1915 



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, 273-5 f^' 

 Height oj Wind Instruments 72 ft. 



MONTHLY SUMMARY. 



Pressure. In inches. 



Maximum reduced to freezing, 29 93,24th, 8 A. 



28th, 8 A. 

 Vlinimum reduced to freezing. 29.19, 8th, 7 p. 

 Reduced! maximum reading, 30.22, 24th, 8 A. 

 Iteducedt minimum reading, 29. ,48 Sth, 7P. 



Mean semi-daily reduced, 29.923 



Montlily range 0.74 



*Air Temperature. In Degrees Fahr. 



Highest 910, 31st, 3 p. 



Lowest, 48.0, 7th, 4;30A. 



Mean hourly, 68.9 



Mean of means of max. and min 69.9 



Mean sensible (wet bulb), 64.5 



.Monthly range, 43-o 



Highest mean daily, 76.9, 3ist 



Lowest mean daily 61.2, 2d 



.Mean maximum, 80.4 



VIean minimum, ... . . .... 59.6 



Mean daily range 20.8 



Greatest daily range 3i-5. Ut'i 



Least daily range, 7-o. ist 



Humidity. 



Mean dew point, 62.1 



Mean force of vapor 697 



Mean relative humidity, 82.1 



Precipitation. In inches. 



Total precipitation, 9- 13 



Number of days on which .01 inch or more 



rain fell 20 



♦Temperature in ground shelter. 

 I Reduced to freezing and sea-level. 



Wind. 



Total movement, 2908m. 



Greatest daily movement, .... 251m., gth 



Least daily movement 2ini., 15th 



Mean daily movement, 94 ni. 



Mean hourly velocity, 3-9»i- 



Maximum pressure per square foot, 16.0 lbs.= 



57m. per hour, ?th, gA., S.S.E. 

 Maximum velocity for 5 minutes, 48m. per 



hour, 5th, loA., S. S.E. 

 Prevailing Direction, Southwest. 



Summary. 



South Southwest 29 per cent. 



South 10 " " 



West Southwest 10 " 



Northwest 10 " 



Other directions 41 " 



Weather. 



Mean cloudiness observed, .... 49 per cent. 

 Total, cloudiness recorded by the Sun Ther- 

 mometer, 271 hrs. = 59 per cent. 



Number of clear days, o 



Number of fair days, i7 



Number of cloudy days, 14 



