METEOHOLOGICAL OBSERVATORY 



OF THE 



Hatch Experiment Station, 



MASSACHUSETTS AGRICULTURAL COLLEGE, 



.a.1!wi::e3:ei?,sx. 



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



Height of instruments above ground^Slft. Above sea level, 273.5 ft. ** 



BULLETIN No. 108. 



DECEMBER, 1897, 



MONTHLY SUMMARY. 



Pressure, In iuche3. 

 Maximum reduced to freezing, . 30.28, 3ci, 10a- 

 Minimum reduced to freezing, 2S. 86, 31st, 1'2 P. 

 Reducedt maximum reading, . ao.iiO, 3d,10A. 

 Reduced! min. reading, . . . 2i).18., 31st, 12 p. 



Mean reducedf, 30.036 



Montlily range 1.42 



*A.ir Temperature. In Degrees Fahr. 



Higiiest, 59.0; 11th, 3 p. 



Lowest -3.5, 29th, 5 A. 



Mean -28.8 



Mean of means of max. and min., .... 28.3 



Mean 8ensible(wet bulb), 28.2 



Monthly Range 62.5 



Highest mean daily 50.5,11th 



Lowest mean daily 10.7, 24tli 



Mean maximum, 35.3 



Mean minimum 21.3 



Mean daily range 14.0 



Greatest daily range, 30.5, 29th 



Least daily range, 4.0, Slh 



Hutniditi/. 



Mean dew point, 24.2 



Mean force of vapor 175 



Mean relative humidity, 83.9 



Wind. 



Prevailing Direction, West Xorth West. 



Summary. 



North Northwest 13 per cent 



Soutli South West, 13 " 



West North West 16 " " 



North West, 19 " " 



North 10 " " 



Other directions 29 " " 



Total movement, 4068 m. 



Greatest daily movement, . . . 340 m., 18tli 



Least daily movement, 28m., 9th 



Mean daily movement 131.2 m. 



Mean hourly velocity 5.5 m. 



Maximum pressure per square foot, 12 lbs =. 



49 m. per hour, 8 a., 18th, W.N.W. 

 Jf recipitaiion. In inches. 



Total precipitation 7.23 



Number of days on which .01 inch or more 



rain or melted snow fell, 12 



Snow total in inches 9.5 



IVeatJier. 

 Mean cloudiness observed, . . 68.0 per cent. 

 Total cloudiness recorded by the Sun Ttier- 



mometer, . . . 175 hours or 65.0 per cent. 



Number of clear days 6 



Numberof fair days 7 



Number of cloudy days 18 



Bright Sunshine. 

 Number of Hours recorded, 108 hours or 355t 

 Rain, 4tli, .'.th, 12th, 14th, 15th, 17th. 

 Snow, lst,3d, 7th, 18th, 2oth, 21st, 26th, 29th, 



31st. 

 Hail, 17th. 

 Aurora, 21st. 

 Gales, of 35 or more miles per hour, 40m., 



2d, W.N.W. ; 47m., 5th, W.N.W.; 44 m., 



17th, W.; 49m., 18th, W.N.W". ; 41m., 21th, 



W.N.W.; 35m., 27th, W.N.W. 



* Temperature in ground shelter. 



t Reduced to freezing and sea level. 



* * Determined from levels of B. & M. R. R. 



