No. 4.] 



REPOKT OF SECRETARY. 



XIX 



Meteorological Observatory of the Hatch Experi- 

 ment Station (Massachusetts Agricultural Col- 

 lege), Amherst. 



Annual Summary for 1897. 



Pressure {in Inches). 

 Maximum reduced to freezing, 30.54, March 



1, 7 A.M. 

 Minimum reduced to freezing, 28.82, Nov. 9, 



7. P.M. 

 Maximum reduced to freezing and sea level, 



30.88, March 1, 7 a.m. 

 Minimum reduced to freezing and sea level, 



29.12, Nov. 9, 7 P.M. 

 Mean reduced to freezing and Bea level, 



30.014. 

 Annual range, 1.76. 



Air Temperature {in Degrees F.).* 

 Highest, 91.5, Sept. 10. 

 Lowest, —11, Feb. 1. 

 Mean, 46.C. 



Mean of means of max. and min., 46.8. 

 Mean sensible (wet bulb), 43.7. 

 Annual range, 102.5. 

 Highest mean daily, 78.1, July 9. 

 Lowest mean daily, 5.0, Jan. 19. 

 Mean maximum, 57.1. 

 Mean minimum, 36.5. 

 Mean daily range, 20.6. 

 Greatest daily range, 47.0, Oct. 4. 

 Least daily range, 3.5, Nov. 19. 



Humidity. 

 Mean dew point, 39.6. 

 Mean force of vapor, .402. 

 Mean relative humidity, 76.4. 



Wind. — Prevailing Direction, West, or S. 

 79° W. Summary {Per Cent). 



South, 19. 



North-west, 12. 



West, 11. 



North, 10. 



South-south-west, 8. 



West. north-west, 8. 



North-north-west, 7. 



South-west, 7. 



Other directions, 18. 



Total movement, 54,220 miles. 



Greatest daily movement, 400 m., Jan. 26, 



Feb. 3. 

 Least daily movement, 11 m., Feb. 1. 

 Mean daily movement, 146.8 miles. 

 Mean hourly velocity, 6.1 miles. 

 Maximum pressure per square foot, 22 



pounds = 66 miles per hour on May 10, 



2 P.M , W. S. W. 



Precipitation {in Inches) . 

 Total precipitation, rain or melted snow, 



57.05. 

 Number of days on which .01 or more 



rain or melted snow fell, 127. 

 Snow total in inches, 52.8. 



Weather. 

 Mean cloudiness observed, 51 4 per cent. 

 Total cloudiness recorded by sun thermom- 

 eter, 2209 hours ^50.5 per cent. 

 Number of clear days, 108. 

 Number of fair days, 109. 

 Number of cloudy days, 148. 



Bright Su7ishine. 

 Number of hours recorded, 2325 bourse 

 50.1 per cent. 



Dates of Frosts. 

 Last, May 8. 

 First, Sept. 22. 



Dates of Snoio, 

 Last, April 27. 

 First, Nov. 12. 

 Total days of sleighing, 38. 



Oales of 50 or More, Miles per Hour. 

 Jan. 18, 61 m., W.; Jan. 23, 55 m., W. N. 

 W.; Jan. 25, 52 m., W.N. W. : Jan. 26, 

 55 m., N.N. W.; March 4,51m., N. W.; 

 March 13, 51 m., W. N. W. ; March 15, 

 52 m., W. N. W.; April 19, 53 m., 

 N. W. ; May 10, 66 ra., W. 8. W. ; Aug. 

 15, 53 m., S. S. W.; Sept. 26, 64 m., 

 N. W.; Nov. 9, 63 m., W. 



J. E. OSTRANDER, Meteorologist. 

 A. C. MONAIIAN, Observer. 



Temperature in ground shelter. 



