METEOROLOGICAL OBSERVATORY 



Hatch Experiment Station 



MASSACHUSETTS AGRICULTURAL COLLEGE. 



^^IvIiiEI^ST. 



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



Height of barometer above ground, 31 ft. Above sea level, 2^3.^ ft. 

 Height of Wind I/istruments 72 ft. 



BULLETIN No. 132. 



DECEMBER, 1899. 



MONTHLY SUMMARY. 



Pressure. In inches. 



Maximumreduced to freezing, 30.36,17th, 7 A 

 Minimum reduced to freezings, 28.79, 24th, 8 r 

 Reducedt maximum reading, 30.6S, 17th, 7 A 

 Reducedt minimum reading, 29.10, 24th, 8 p 



Mean tri-daily reduced, 30.0321 



Monthly range • 1.5S 



*Ali' Teinperatiire. In Degrees Fahr. 



Highest 61.0, i2th, 10 A. 



Lowest 2.0. 31st, 7 A. 



Mean hourly, 3o-8 



Mean of means of max. and nun., . . . .31.0 



Mean sensible (wet bulb), 29.2 



Monthly range 59-0 



Highest mean daily, 54.7,12th 



Lowest mean daily 8.3, 30th 



Mean maximum, 38. 5 



Mean minimum .... 23.5 



Mean daily range 15.0 



Greatest daily range 27.0, 1st 



Least daily range 4.5. jth 



Hiiniiditi/. 



Mean dew point, 25.1 



-Mean force of vapor, 194 



Mean relative humidity, . . . • ... .79.4 

 Frecipittition. In inches. 



Total precipitation, . ■ 2.00 



Xumher of days on which -oi inch or more • 



rain or melted snow fell, 8.0 



Snow total in inches, o.; 



Snow on ground at end of month o 



Wind. 



Total movement, 4142 m 



Greatest daily movement, .... 371 m., 12th 



Least daily movement 4 m., iSth 



Mean daily movement, i33-3 m. 



Mean hourly velocity, 5.6 m. 



Maximum pressure per square foot, 15.5 lbs.= 



56 m. per hour, 12th, i p., S.W. 

 Prevailing Direction, West. 

 Summary. 



North, 13 per cent. 



Northwest, 13 " " 



North, northwest, 10 " " 



West, 16 " " 



South, 10 " " 



Southwest, . . iq " " 



Other directions, 19 " " 



M'enUier. 

 Mean cloudiness observed, .... 52 per cent. 

 Total cloudiness recorded by the Sun Ther- 

 mometer, . . . . 141 hrs. =50 per cent. 



Numterof clear days, 9 



Number of fair days, 12 



Number of cloudy days, 10 



Krlfflit Sunshine. 



Number of hours recorded, . . . 142 hrs. = 5o)i 

 Rain. ist. 2d, 3d, 4th. nth, 12th, 15th, 19th, 



24th. 



dnou-, 5th, Sth, 17th, 24th. 



Hail, 12th. 



Gales, 35 miles or more per hour, 40m., 4th, 



N.W.: 40m.. 5th, W.N.W.; 40m., 8th. 



N.W.: 35m., i8th. S.W.; 56m., 12th, S.W.; 



46 m., 15th, N.W.:36m., 19th, S.W. 



* Temperature in ground shelter, 

 t Reduced to freezing and sea-level. 



