METEOROLOGICAL OBSERVATORY 



OF THE 



Hatch Experiment Station, 



MASSACHUSETTS AGRICULTURAL COLLEGE, 



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



Height of barometer above ground, 31 ft. Above sea level, 2'jj.§ ft. 

 Height of Wind Instruments 72 ft. 



BULLETIN No. 192. DECEMBER, 1904. 



MONTHLY SUMMARY. 



Pressure. In inches. 

 Maximum reduced to freezing, 30.22, 26th, 11 a. 

 Minimum reduced to freezing, 28.80, 28th, i p. 

 Reduced! maximum reading, 30.54, 26th, 11 a. 

 Reduced^ minimum reading, 29.11, 28tli, i p. 



Mean semi-daily reduced, 30.021 



Monthly range, 1.43 



*Air Temperature. In Degrees Fahr. 



Highest 43-5. 23d, 5 P- 



Lowest, -3-;. 15th, 7.30 A. 



Mean hourly, i9-6 



Mean of means of max. and min 19.4 



Mean sensible (wet bulb), 174 



Monthly range, 47-o 



Highest mean daily 36.0,23d 



Lowest mean daily, 5-3i i5th 



Mean maximum, 28.3 



Mean minimum, 10.5 



Mean daily range i7-S 



Greatest daily range, 32-0, 24th 



Least daily range, 7o>3d 



H nmidity . 



Mean dew point 12.6 



Mean force of vapor 112 



Mean relative humidity, 77.S 



t'recipitation. In inches. 



Total precipitation, 2.75 



Number of days on which .01 inch or more 



rain or melted snow fell • • 8 



Total snow in inches, 11 



Snow on ground at end of month 2 



* Temperature in ground shelter, 

 t Reduced to freezing and sea-level. 



JVinU. 



Total movement, 3940 m. 



Greatest daily movement, . . . 340 m., 24th 



Least daily movement S m., 17th 



Mean daily movement 127m. 



Mean hourly velocity, 5-3ni. 



Maximum pressure per square foot, 9.5 lbs.= 



44m. per hour, 29th, 3 p., W.S.W. 

 Prevailing Direction, Northwest. 

 Summary. 



North, Northwest, 16 per cent. 



South, 10 " " 



North ....•• 29 " " 



Northwest, 13" " 



Other directions, 32 " " 



Weather. 

 Mean cloudiness observed, .... 57 per cent. 

 Total cloudiness recorded by the Sun Ther- 

 mometer, . ... 168 hrs. =59 per cent. 



Numter of clear days, 7 



Number of fair days, 8 



Number of cloudy days, 16 



Bright Snuskine. 



Number of hours recorded, . . . 115 hrs. =41^ 



Rain, 23d, 25th, 26th, 27th, 28th. 



Snow, 4th. 5th, 8th, 13th, i8th, 19th, 20th, 



2ISt, 25th, 26th, 27th, 30th. 



Oales,2S miles or more per hour, 36m. 24th, 



N.N.E.;38m. 2Sth, W.: 44m.29th, W.S.W. 



Days of Sleighing, 6 



