METEOROLOGICAL OBSERVATORY 



OF THE 



Hatch Experiment Station, 



MASSACHUSETTS AGRICULTURAL COLLEGE, 



Latitude, 42° 23' 48.;)" N. LongiiKde, 72° 31' 10" W. 



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



BULLETIN No 45. 



SEPTEMBER, 1892. 



mONTHLY SUMiVlARY. 



Pressure. In inches. 

 Actual in.axinuini reading,. . 30.13, Sth, 9 a. 

 Actual miniunun reading, . 29.18, •2(;th,7-30 a. 



Mean reduced to sea level, 30.103 



Montlily range 95 



*Ah' Tempera til re. In Degrees Fahr. 



Highest 76; 80. 



Lowest 40.; 31. 



.Mean, 60.6; 59.3 



Monthly Range, 15.4; '20.7 



Highest mean daily, 70.1; 71. 



Lowest mean daily, 52.3; 51. 



Mean maximum, 69.7; 73. 



Mean minimum, 51.2; 45.6 



Mean daily range, 18.5; 27.4 



Greatest daily range, 30. ; 45. 



Least daily range 5.; 11. 



Humidity. 



Mean dew point 51.9 



Mean force of vapor, .5770 



Mean relative humidity, 70 



Wind. 



Prevailing Directions. 



South 18 per cent. 



South, Southwest, 17 " " 



Southwest, 13 " 



Northwest, 9 " " 



Other directions 43 " " 



Total movement 3672 m 



Greatest daily movement, .... 330 m., 14th 

 Least daily movement, 24 m. 9th, 



Mean daily movement 122 m- 



Mean hourly velocity, 5.1 m. 



Maximum pressure per squai-e foot, 15.ilbs.= 

 56 m. per hour, 26th, at 1-30 P. 

 * P reclpitation. In inches. 

 Total precipitation, 1.29; 2.16 



Weather. 



Mean clouiliness observed, . . . 29 per cent. 



Number «f clear days, 13 



Number of fair days, H 



Number of cloudy days, 6 



Total cloudiness recorded by the Sun Ther- 

 mometer, ... 139 hours or 37 per cent 

 Number of days on which .01 inch or more 



rain fell, 5 



Frost, 30th. 



Bright Sunshine. 



Number of Hours recorded 234 



Rain, 6th, 13th, 14th, 19th, 22nd, 23rd, 24th, 



26th. 

 Thunder and Ziightning, 26th. 

 Mean Ozone, 43 per cent. 



Halos. 



Solar 4th, 10th, 19th, 21st. 



Lunar, 3rd. 



Gales, of 35 or more miles per hour,45,6th, W . 

 N. W.; 36, 14th, S.; 39, 19th, N. ; .56, 26th, W. 

 N. W.;43, 27th, W. N. W. 



♦The first figures denote readings at top of tower, the second at base. 



