METEOROLOGICAL OBSERVATORY 



Hatch Experiment Station, 



MASSACHUSETTS AGRICULTURAL COLLEGE, 



Latitnde. l-.>° 23' 48. ;V' N. Lonoitiule, 72° 31' 10" W. 



Height of instraments above ground, 51 ft. Above sea level, 260 ft. 



BULLETIN Na 48. 



DECEMBER, 1892. 



MONTHLY SUMinARY. 



Pressure. In inches. 

 Actual inaxiinnin reading, . 30.23, l'21h, 8a. 

 Actual niininiuni reading, . . 29.22, 2.5th, liP. 



Mean reduced to sea level, 30.01 



Montlilj' range, 1.01 



*Air Tetnperattire. In Degrees Fahr. 



Highest 41. ; 46. 



Lowest, 5. ; -1. 



Mean 28.5; 26.3 



Monthly Range 36. ; 47. 



Highest mean daily, 3S.6; 37. 7 



Lowest mean daily 9. ; 10. 



Mean ma.xinmm, 33.5; 35.4 



Mean minimum, 23.8; 17.3 



Mean daily range, 9.7; 18.1 



Greatest daily range, 21. ; 33. 



Least daily range, 1. ; 6. 



Humidity. 



Mean dew point, 20.5 



Mean force of vapor, 1771 



Mean relative humidity 70.3 



Wind. 

 Prevailing Directions. 



North West, 24 per cent. 



North 13 " 



North Northwest, !2 " " 



.smith West, 11 " 



Other directions, ....... 40 " " 



Total movement, 4522 m. 



Greatest daily movement, . . . 3:^5 ni., 24th. 

 Least daily movement, 20 m. 10th, 



Mean daily movement, . . ., 145 m. 



Mean hourly velocity, 6. m. 



Maximum pressure per square foot, 13ill)8.= 

 52 m. per hour, 1st, at 12 M. 



* Precipitation. In inches. 



Total precipitation, 56; 1.01 



Weather. 



Mean cloudiness observed, . . .45 per cent. 



Number of clear days, 9 



Number of fair days 8 



Number of cloudy days, 14 



Total cloudiness recorded by the Sun Ther- 

 mometer, . . . 139 hours or 49 per cent. 



Number of days on which .01 inch or more 

 rain or melted snow fell, 4 



Number of inches of snow on the ground at 



the close of the monih 



Bright Sunshine. 



Number of Hours recorded, 144 



Rain, 6th, 7th, 8th, 14th. 



Smo«'. 1st, 3rd, 14th, 15th, 17th, 19th, 23rd, 

 2.5th. 



Total fall in inches, 3 



Hail, ... ....... 6th. 



Aurora Boreal is, 4th. 



Mean Ozone, 34 per cent. 



Hal OS. 



Solar, 6th, 13th, 16th, 20th, 21st, 31st, 



Lunar, 27th, 31st. 



Grtifs, of 85 or more miles per hour, .52, 1st, 



N.; 36, 4tli, N. W.; .37,11th, N. W.; 47, 



20th, N.N. E.; 47, 22nd, N.W.; 45. 2nh. 



N v\'. ; 48, 2.5th, N.W. ; 47, 26lh, .N.W. ; 37, 



ii7th, N.;:i6, 2Sth,N.N.E. 



♦The first Hgurcs rienotc readings at top of tower, tlie second at base. 



