Xll 



BOAKl) OF AGRICULTURE. [Pub. Doc. 



Meteorological Observatory of the Hatch Experiment Station, 

 Massachusetts Agricultural College, Amherst. 



Latitude, 42° 23 48.5" N. Longitude, 72° 31' 10" W. Height of instruments above ground 

 51 feet. Above sea level, 260 feet. 



Annual Summary for 1891. 



Pressure. 

 [In Incbes.] 

 Actual max., reading, 30.44, Nov. 19, 10 a.m. 

 Actual min., reading, 28.40, Jan. 12,6 a.m. 

 Mean reduced to sea level, . . 30.018 

 Annual range 2.04 



* Air Temperature. 



[In degrees Fabr.] 



Highest, .... 91.5; 94, June 16 



Lowest 0.0 ;-6, Feb. 15 



Mean 49.7; 49.1 



Annual range, .... 91.5; 100 



Highest mean daily, 79.6 June 15, 16; 77.3 

 Aug. 11. 



Lowest mean daily, 

 Mean maximum, 

 Mean minimum, 

 Mean daily range, 

 Greatest daily range, 

 Least daily range, 



. 11.3; 9.3, Mar. 2 

 57.2; 59.7 

 41.8; 36.7 

 . 15.4; 23 



. 39; 51.5, May 10 

 2; 6.5, Mar. 9, Dec. 25 



Humidity. 

 Mean dew point, 

 Mean force of vapor, . 



Mean relative humidity, . 



Wind. 

 [Prevailing Directions.] 



North, 



South, 



North-west, .... 

 South, South-west, . 



40.1 

 4645 



66.8 



190 



13# 

 12# 

 11<« 



Total movement, 

 Greatest daily movement, 

 Least daily movement, 

 Mean daily movement, 

 Mean hourly velocity, 



45,212 m. 



443 m. Mar. 14 



. 3m. Jan . 1 



.151.3 m 



. 6.3 m 



Maximum pressure per square foot, I64 

 lbs.=57 m. per hour, Jan. .'3, 3 p.m. 



* Precipitation. 

 Total rainfall or melted snow, 34.82 in., 



46.80 in. 

 Number of days on which .01 inch of rain or 



melted snow fell, .... 112 



Total snow fall in inches, . . . 54J 



in other. 



Mean cloudiness observed, . . 53# 



Total cloudiness recorded by the sun ther- 

 mometer, 2,220 hours, or 50 



Number of clear days, . . . 145 



Number of fair days, . . . 103 



Number of cloudy days, . . . 117 



Briglit Sunshim ■ 

 Number of hours recorded, . . 2,245 

 Mean ozone 48# 



Last, 

 First, 



Last, 



First, 



Dates of Frosts. 



Dates of S?iow. 



May 19 

 Oct. 12 



May 5 

 Nov. 26 



C. D. Wabner, Meteorologist. 

 A. T. Beai.s, Assistant. 



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



