No. 189.] 41 



2. Barometer and Rain Gauge. 



1883. Mean. 



Months. 



January 29.45 



February 29 . 55 



March 29.42 



April 29.44 



May 29.46 



June 29.43 



July 29.46 



August 29.52 



September 29.58 



October 29.55 



November 29.43 



December 29.52 



Mean, 29.48 



Highest 

 mean. 



Lowest 

 mean. 



Highest. 



Lowest. 



Range. 



M'thly avge. 



Water, water for 



27 years. 



30.11 



28.93 



30.16 



28.83 



1.33 



2.23 



2.046 



30.15 



29.16 



30.17 



28.92 



1.25 



2.44 



2.061 



29.93 



29.08 



29.94 



28.94 



1.00 



1.49 



2.026 



29.79 



29.22 



29.83 



28.59 



1.24 



2.79 



2.412 



29.73 



28.93 



29.74 



28.94 



0.80 



1.86 



2.856 



29.66 



28.94 



29.68 



28.92 



0-76 



1.37 



3.031 



29.70 



29.27 



29.71 



29.25 



0.46 



5.03 



3.386 



29.79 



29.30 



29.83 



29.27 



0.56 



3.70 



2.716 



29.91 



29.19 



29.94 



29.13 



0.81 



1.51 



3.289 



29.98 



29.23 



30.03 



29.15 



0.88 



2.72 



3.169 



29.89 



29.11 



29.94 



29.04 



0.90 



2.97 



2.759 



30.05 



28.78 

 .49 



30.06 28.68 



1.38 

 .,1.583 



1.98 

 30.09 



2.500 



29, 



29 



.44 Yr 



32.251 



The mean height on the barometer for 1863, is 29.48 inches, 

 and the range for this year, 1.58 inches. The annual means 

 vary from 29.44 and 29.63 inches, or 0.19 inch, and their mean 

 is 29.54 inches. The variations in the daily observations are 

 between 30.47 and 28.24; or, as it was on the zero barometer, 

 28.14. The next higher to this was 28.50, and above these 

 28.54, 28.66, 28.70, but rarely below 28.78. All the low and 

 rapid depressions, high wind, sometimes a tornado, sometimes 

 rain or snow, attended or soon followed. 



In some years, as 1861, the barometer showed a height below 

 29 inches in all the months except January and August, while in 

 others, as in 1863, the height was above 29 inches from June 

 2d to December 14th. Often the period of higher elevations 

 continues two or four days, fluctuating somewhat; but the peri- 

 ods of depression are shorter. 



The water of the year is 30.09 inches, while the average is 

 32.251 inches, or about one-sixteenth above that measured for 

 this year. The last column of the table, the monthly average, 

 contains some singular differences. 



3. Special Phenomena. 

 1863, April 3. Magnificent Jiurora Borealis. 



About 8 o'clock p. m., in a clear sky, two cotton-like bands or 

 arches rose from the horizon, one N. of E. and the other N. of 

 W., and soon met on the meridian N. of the zenith, perhaps 50 

 degs., narrower at each end, but widening upwards to 4 or 5 degs. 

 in breadth, and the arch nearly parallel to the equator, the west 



[Assem. No. 189.] 6 



