BULLETIN No. 300. 



DECEMBER, 1913 



Meteorological Observations 



AT THE 



MASSACHUSETTS 



AGEICULTURAL EXPERIMENT 



STATION. 



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



Height of barometer above ground, 51 ft. Above sea level, 21^.^ ft. 

 Height of Wind Instruments 72 ft. 



MONTHLY SUMMARY. 



Pressure. In inches. 



Maximum reduced to freezing, 30.16. ist, A. 

 Minimum reduced to freezing, 28.82, Sth, 3 A. 

 Reducedt maximum reading, 30.47, ist, A. 

 Reducedt minimum reading, 29.13, Sth, 3 A. 



Mean semi-daily reduced, 30.013 



Montlily range 1.34 



*Air Temperature. In Degrees Fahr. 



Higliest, 53.0, 7th, 6p.; 14th, 2P 



Lowest, 5.0, 28th, 8:30A 



Mean hourly, 31.3 



Mean of means of max. and min., .... 32.0 



Mean sensible (wet bulb), 27.4 



Montlily range, 4S.0 



Highest mean daily, 43-7, 5th 



Lowest mean daily 12.4, 2Sth 



Mean maximum 40.7 



Mean minimum, 23.3 



Mean daily range 17.4 



Greatest daily range, 27.5, 30th 



Least daily range 7.5,25th 



Huinitlity. 



Mean dew point, 23.5 



Mean force of vapor, 169 



Mean relative humidity, 81.2 



Precipitation. In inches. 



Total precipitation, 3.38 



Number of days on which .01 inch or more 



rain fell • 9 



Total snow in inches 4 



Temperature in ground shelter. 

 Reduced to freezing and sea-level. 



Wind. 



Total movement, 4400m. 



Greatest daily movement, .... 350m., Sth 



Least daily movement, iini. ,29th 



Mean daily movement 142 m 



Mean hourly velocity, 5-9 m 



Maximum pressure per square foot, 7.0 lbs.= 



37m. per hour, 26th, 7A., N.N.E. 

 Maximum velocity for 5 minutes, 33ni. per 



hour, Sth, 5A., W.N.W. 

 Prevailing Direction, North Northwest. 



Summary. 



Northwest 19 per cent 



North Northeast 19 " 



North 10 " 



South 10 " 



South Southwest 10 " 



West Northwest 10 " 



North Northwest 10 " 



Other directions 12 " 



Weather. 



Mean cloudiness observed, .... 45 per cent 

 Total cloudiness recorded by the Sun Ther- 

 mometer, i62hrs.=57 per cent. 



Number of clear days, 7 



Number of fair days, 10 



Number of cloudy days, 14 



Bright Sunshine. 



Number of hours recorded, . . 121 hrs=43?(. 

 Rain, ist. 7th, Sth, 23d, 24th, 25th, 26th. 

 Snow, Sth, lotli, nth, iSth, 25th, 26th. 

 Days of Sleighing, 5. 



Gales, 35 or more miles per hour : 36m, Sth, 

 W.N.W.; 36m, 14th, W.; 37m, 26th, N.N.E. 



