xxxviii BOARD OF AGRICULTURE. [P. D. No. 4. 



Meteorological Observatory of the Hatch Experi- 

 ment Station (Massachusetts Agricultural Col- 

 lege), Amherst. 



Annual Summary fou 1900. 



Pressure {in Inches). 

 Maximum reduced to- freezing, 30.42, Feb- 

 ruary -IS, 7 A.M. 



Minimum reduced to freezing, 28.55, Feb- 

 ruary 25, i A.Ji. 



Maximum reduced to freezing and sea 

 level, 30.75, February 28, 7 A.M. 



Minimum reduced to freezing and sea 

 level, 28.86, February 25, 4 A.M. 



Mean reduced to freezing and sea level, 

 29.985. 



Annual range, 1.89. 



Air Temperature (in Degrees F.).* 

 Highest, 96.0, August 6, 5.30 P.M. 

 Lowest, — 8.0, February 3, 6.30 a.m. 

 Mean, 48.3. 



IMean of means of max. and min., 48.1. 

 Mean sensible (wet bulb), 45.0. 

 Annual range, 104.0. 

 Highest mean dally, 84.0, July 17. 

 Lowest mean daily, 3.4, February 2. 

 Mean maximum, 59.1. 

 Mean minimum, 37.3. 

 Mean daily range, 21.8. 

 Greatest daily range, 47.5, May 27. 

 Least daily range, 2.5, May 19. 



numidity. 



Mean dew point, 39.2. 

 INIean force oi vapor, .436. 

 Sloan relative humidity, 72.3. 



Wind. — Prevailing Direction West. Sum- 

 mary (Per Cent). 



Nortli-west, 15. 



North, 12. 



South-west, 11. 



South, 10. 



West, 10. 



Otiier directions, 42. 



Total movement, 50,503 miles. 



Greatest daily movement, 435 miles, Feb- 

 ruary 26. 



Least daily movement, 1 mile, November 

 29. 



Mean daily movement, 138.4 miles. 



Mean hourly velocity, 5.8 miles. 



Jlaximum pressure, per square foot, 30.5 

 pounds = 78 miles per hoiir, February 

 25, 11 P.M., W.N.W. 



Preci.jntntion (in Inches). 

 Total precipitation, rain or melted snow, 



51.67. 

 Number of days on which .01 or more 



rain or melted suow fell, lol. 

 Snow total, in inches, 37.0. 



Weather. 

 iSIean cloudiness observed, 55 per cent. 

 Total cloudiness recorded by sun ther- 

 mometer, 2,238 hours = 50 per cent. 

 Numljer of clear days, 83. 

 Number of fair days, 144. 

 Number of cloudy days, 138. 



Bright Sunshine. 

 Number of hours recorded, 2,216 = 50 per 



cent. 



Dates of Frosts. 



Last, May 29. 

 First, September 15. 



Dates of Snow. 

 Last, April 9. 

 First, November 9. 

 Tot^d days of sleighing, 27. 



Gales of SO or More Miles per Hour. 

 January 26, 64 miles, N.W. ; January 27, 55 

 miles, N.W.; February 5, 53 miles, N.; 

 February 13, 55 miles, N.W. ; February 

 14, 50 miles, N.W.; February 22, .52 

 miles, N.E.; February 2o, 78 miles, 

 W.N.W. ; February 26, 51 miles, N.W. ; 

 IMarch 2, 57 miles, N.W. ; March 4, 53 

 miles, N.W. ; April 1, 50 milcs,W.N.W.; 

 April 26, 51 miles, N.N.E.; May 1, 52 

 miles, N.W.; May 5, 66 miles, N.W.; 

 June 30, 50 miles, N.AV.; July 7, 68 

 miles, S.W.; August 6, 57 miles, 

 N.N.W. ; September 12, 60 miles, S. W. ; 

 November 9, 58 miles, N.N.W. ; No- 

 vember 10, 60 miles, N.N.W. ; Decem- 

 ber 9, 51 miles, S.S.W. 



* Temperature in ground shelter. 



