BULLETIN No. 12, DECEMBER, 1889. 



METEOROLOGICAL OBSERVATORY 



OF lllK 



Hatch Experiment Station, 



MASSACHUSETTS AGRICULTURAL COLLEGE, 



Latitude, 42° 23' 4S.r)" N. Louoitude, 72° :\\' 10" VV. 



Hnight of instrmnents above ground, 51 ft. Above sea level, 260 ft. 



MONTHLY SUMMARY. 



freHsiire, In inches. Actual niaxiniuni readinji: 30.(i4 ; actual niininuun reatliiig -28.915; 

 Mean rediiceil to .32'-" P., >9.8>9; Monthly Range, 1.72.5. 



Air Tf-inpi-vfitiire. In Decrees Fahrenheit. Higlu-st, at to]) of tower, 04.0"; at hase of 

 tower, ()4.0"; Lowest, at top of tower, 4.0'-'; at base of tower, '^.f)'^; Mean, 3.T.0'-'; Monthly 

 Range, fyiA)-'; Highest Mean Daily, .W. ,">'-'; Lowest Mean Daily, 11. S"^; .Mean Maximum, 44.8'^; 

 Mean Minimum, -24. J-^; Mean Daily Range, '20..'i>'; Greatest Daily Range, .■?(;. 0". 



irnitihliti/. Mean Dew Point, 30.9^; Mean Force of Vapor, .2406; Mean Relative Huniitt- 

 ity, 7.1.2. 



M'lHf/. Previiiling Direction, N. W.; Total Movement, 444.') miles; Greatest Daily 

 Movement, 337 miles, 27th: Least Daily Movement, 19 miles, ISth; Mean Daily Move- 

 ment, 143.4 miles. Mean Hourlv Velocity, o.O miles ; Maximum Pressure per Square Foot 

 29 ll)s.=7(j m. |)er hour, 2(ith, at 4-30 p. m. 



Precipitation. In inches. Total Precipitation, 2. .19 in. ; at base of tower 3..57 in. 



Wi-ftther. Mean Clouilincss observed, 01. i)er cent; Xumlierof Clear Days, 9; Number 

 of Cloucly Days, 18; Number of Fair Days, 4; Total Cloudiness recorded by the .Sun 

 Thermometer, 179 hrs, or (!0.0 per cent. Number of days on which .01 inches or" more rain 

 fell, 12. 



Brif/ht Sunshine. Number of Hours Recorded, 108. 

 .Snoir, .'Jth, 14th and 2Gth. Total falli in inches, 6 .3-4. 

 Frost, 1st, 10th, 22nd, 29th, and 31st. 

 Hnlos, Lunar, 30th. Meteors, lOth. Hale, 26th. 



DAILY SUMMARY, 



Dec. 1. Barometer reduced to 32° F., max. 30.218, min. 30.025, mean 30.132- 



♦Temperature, max. 45", 48''. 3 p.m., min. 22°, IG*^. 6 a. m., mean hourly 33.0°. 



Sun Thermometer, max. 121^, 1.30 p.m., bri<>-ht sunshine 9 hrs. 



Mean dew point 32.7", mean force vapor .2590, mean humidit.y 66.7. 



Wind, S.W., total mov.ement, 63 m., mean hourly velocity 2.6. m., max. pres- 

 sure. 2 lbs.= 20 m. per hour, 12 m. Ozone 2. 



2. Barometer reduced to 32° F. , max. .30.020, rain. 29.673, mean 29. 745. 

 Temperature, max. 49", 50", 11 a.m.. min. 30", 27°, 2 a.m., mean hourlv 41.0°. 

 Sun Thermometer, max. 120«», 11.30 a.m., briirht sunshine 3 1-2 hrs. 



Mean dew point 35.0", mean force vapor .2910. mean humidity 63.3. 

 Wind, W.. total movement 226 m., mean hourlv vel. 9.4 m., max. pressure 

 11 1-2 lbs. =48 m. per hour, 11.30 a.m. Ozone 4. 



3. Barometer reduced to 32" F., max. .30.955, rain. 29.622, mean 29.762. 

 Temperature, m,ax. 46.5", 4.5.5", 1 a.m., min. 4", 3.5", 12 p.m., mean hourly 31 .2". 

 Sun Thermometer, max. 45", 1 p.m., bright sunshine 0. 



Mean dew point 21.3°, mean force vapor .2576. mean humidity 69.0. 

 Wind. N.N.E., total movement 229 m.. mean hourly vel. 9.5 m.. max. pres- 

 sure 13 lbs. ^51 ra. per hour. 4 p.m. Ozone 4. 

 *The first figures denote readings at top of ti>wer, the second at base. 



