METEOROLOGICAL OBSERVATORY 



Hatch Experiment Station, 



MASSACHUSETTS AGRICULTURAL COLLEGE, 



LatitiKlo, 42° 23' 48.5" N. l,ongitnde, 72° 31' 10" W. 



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



BULLETIN No. 27, 



MARCH, 1891 



MONTHLY SUMMARY. 



Pressure. In inches. 

 Actual maximum reading, . 30.26, 2cl, 10 a. 

 Actual minimum reading, . 29.06.5, 13th, 10 p. 



Mean reduced to sea level 30.099 



Monthly range, 1.195 



*^ir Tetnperntiire. In Degrees Fahr. 



Highest ■. . 53. ; 56.5 



Lowest, 3.;— 1. 



Mean, 33.7; 32.7 



Monthly Range, 50. ; j57.5 



Highest mean daily 46.4 ; 46.5 



Lowest mean daily 11.3:9.3 



Mean maximum, 40.3; 42.2 



Mean minimum 27. ; 23.1 



Mean daily range, 13.3; 19.1 



Greatest daily range, 23. ; 31.5 



Least daily range, 2; 6.5 



Bumidity. 



Mean dew point, 22.6 



Mean force of vapor, 2149 



Mean relative humidity, 63.7 



Wind. 

 Prevailing Directions. 



North 33 per cent. 



North North East 16 " " 



North West, . . . • 16 " 



South S " 



Other directions 27 " " 



Total movement, 6261 m. 



Greatest daily movement, .... 443 m., 14th 

 Least daily movement 78 m., 3l9t 



Mean daily movement 203 ni. 



Mean hourly velocity 8.4 m. 



Maximum pressure per square foot,105lbs.= 

 46 m. per hour, 14th, at 9 a. 



* Precipitation. In inches. 



Total precipitation, 1.97; 2.99 



Weather. 

 Mean cloudiness observed, . . . 55 per cent. 



Number of clear days, 14 



Number of cloudv days 10 



Number of fair days 7 



Total cloudiness recorded by the Sun Ther- 

 mometer, 175 hours or 47 per cent. 

 Number of days on which .01 inch or more 



rain or snow fell, 9 



Depth of snow, in inches, on ground at close 

 of month, 



Bright Sunshine. 

 Number of Hours recorded 194^ 



Snotv, 3rd, 4th, 7th, 14th, I6th, I9th, 2l8t, 



Total Fall in inches, 9 



Rain, Sth, 9th, 10th, 12th, 16th, 21st, 22d. 



Hail, 21st. 



Axirora, 28th. 



Mean Ozone, 69 per cent. 



Malos. 



Solar, 2d, 27th, 31st. 



Lunar, 17th, ISth, 22d. 



Lunar coronae, 15th, 22d. 



Gales, of 40 or more milesper hour, 43,N.w.. 



10th; s.w. 43, 13th: 46, w. 14th; 41, N.W., 



16th. 



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



