METEOROLOGICAL OBSERVATORY 



OF THE 



Hatch Experiment Station, 



MASSACHUSETTS AGRICULTURAL COLLEGE, 



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



Height of instruments above ground, 51ft. Above sea level, 273.5 ft. ** 



BULLETIN No. I 12. 



APRIL, 1898. 



MONTHLY SLfMiVlARY. 



Pressure. In inches. 

 Maxinunn reduced to freezing, 30.04, 27tli,8A. 

 Minimum reduced to freezing, 29.18, 15tli, 4p. 

 lleducedt maximum reading, 30.34, 27th, 8a. 



Keducedf miu. reading 29.48, 15th, 4P. 



Mean reducedf, 29.927 



-Montlily range 86 



*Air Temperature. In Degrees Fahr. 



Highest, 71,17th, 3 p. 



Lowest, 17.0,6th,6 A.f 



-Mean, 43.0 



Mean of means of max. and min 42.4 



Mean sensible(wet bulb), 39.9 



.Monthly Range 54.0 



Highest mean daily, 58.4, 17th 



Lowest mean daily 25.7, 3d 



Mean maximum, ,51.9 



.Mean minimum, 33.0 



Mean daily range, 18.9 



Greatest daily range, 38.5, 9tli 



Least daily range, 2.5, 5th 



Ifuniiditi/. 



.Mean dew point 34.2 



.Mean force of vapor, 303 



Mean relative liumidity, 72.1 



Wind. 



Prevailing Direction, North North West. 

 Summary. 



North 10 per cent. 



West 13 " " 



North Wes-t, 20 " " 



North North East, 20 " 



Other directions 37 " " 



Total movement, .5477 m. 



Greatest daily movement, . . . 380 m., 28t,h 



Least daily movement 81m., 10th 



-Mean daily movement, 182.6 m. 



Mean hourly velocity, 7.6 m. 



Maximum pressure per square foot, 10.0 lbs = 



45 m. per hour, 1 r., 28th, N.E. 

 Vrecipitation. In inches. 



Total precipitation 3.73 



Number of days on which .01 inch or more 



rain or melted snow fell, 14 



Snow total in inches .... 1 



Weather. 

 Mean cloudiness observed, . . 68.0 per cent. 

 Total cloudiness recorded by the Sun Tlier- 



mometer, . . . 234 hours or 58.0 per cent. 



Number of clear days, 3 



Numberof fair days, 14 



Number of cloudy days, 13 



Sright Sunshine. 

 Number of Hours recordeil, 168 hours or 42^4 

 Ka in, 2d,.5th,6th, 10th, 14th, 1.5th, 16th, 17th, 19th, 



20th,21st, 22d, 23d,24th,25th,26th,2Sth,29th. 



Snow, 2d, 5th, 6th. 



Uail, 19th, 28th. 



Thunder, 11th. 



Ofiles, of .35 or more miles per hour, 38m. ,1st, 



N.W. ; 37m. ,7th, N.W. ; 3.5m., 12th, N.N. E. ; 



43m., 13th, N.N.E.;35m., 17th, W.; 35m., 



1-th, N.W. ; 43m., 21st,W.N.W. ; 41m.,22d, 



W.N.W.; 45m., 28th,N.E.; 38m. ,30th, N.W. 

 Last Frost 27th 



* Temperature in ground shelter. 



t Reduced to freezing and sea level. 



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

 t Other dates also. 



