METEOROLOGICAL OBSERVATORY 



Hatch Experiment Station 



MASSACHUSETTS AGRICULTURAL COLLEGE 



Latitude, 43° 23' 48.5" N. Longitude 72° 31' 10" W. 



Height of barometer above ground, 31 ft. Aboi'c sea level, 2'jj.^ ft. 

 Height of Wind Instruments 72 ft. 



BULLETIN No. 127. 



JULY, 1899. 



MONTHLY SUMMARY. 



Pressure. In inches. 

 Maxinuim reduced to freezing, 29.94, ist, 7A. 

 Minimum reduced to freezing, .'!9.35, 9th, 2 i'. 

 Reduced! maximum reading, . 30.24, ist, 7 A. 

 Reduced! minimum reading, 29.63, 9th, 2 v. 



Mean tri-daily reduced, 29.927 



Montlily range • 51 



*Air Tempcratiire. In Degrees Fahr. 



Highest, 90.0, 27th, 2-30 p. 



Lowest, 43.0, 1st, 5 A. 



Mean hourly, 70.1 



Mean of means of max. and min., .... 6g.8 



Mean sensible (wet bulb), 65.7 



Monthly range, 47.0 



Highest mean daily, 76.7, 6th 



Lowest mean daily, 61.3, 20th 



Mean maximum, 81.3 



Mean minimum, ... 58.2 



Mean daily range, 23.1 



Greatest daily range, 37.0, ist 



Least daily range, 11.0,23d 



Hittnidity. 



Mean dew point, 62.5 



Mean force of vapor, 791 



Mean relative humidity, . . . • .... 75.2 



yrecipifittion. In inches. 



Total precipitation, . • 4.89 



Number of days on which .01 incli or more 

 rain or melted snow fell, 10 



Wind. 



Total movement, 3S91 m. 



* Temperature in ground shelter, 

 t Reduced to freezing and sea-level. 



Greatest daily movement, . . . 240 m., 21st 



Least daily movement 21 m., 15th 



Mean daily movement, ' 125.5 in- 

 Mean hourly velocity, 5.2 



Maximum pressure per square foot, 12 lbs. = 



49 m. per hour, on 12th, 7 P., W. 

 Prevailing Direction, West Southwest. 



Summary. 



Southwest, ig per cent. 



South southwest, 26 " " 



West, 13 " " 



Northwest, 10 " " 



Other directions, 32 " " 



Weather. 



Mean cloudiness observed, .... 50 per cent. 

 Total cloudiness recorded by the Sun Ther- 

 mometer, 203 hrs.=44 per cent. 



Number of clear days, 9 



Number of fair days, 12 



Number of cloudy days, 10 



Bright Sunshine, 



Number of hours recorded, . . . 259 hrs. = 565( 



Rain, 6th. 7th. 8th, 9th. 12th, i6th, 17th, iSth, 

 25th, 26tli, 27th 29th, 30th. 



Thunder and Liijhtniny, 6th, 7th, Sth^ 

 12th, i6th, 27th. 



Oales, 3; miles or more per hour, 49 m., 12th, 

 W. ; 36 ni., !2ist, S.W.; 45 m., 27th, N. 

 W. 



