ELISHA MITCHELL SCIENTIFIC SOCIETY. 5 I 



HUMIDITY. 



The average annual mean humidity is 71.18. January has the 

 highest average 77.24, and February the lowest 68.88. The six 

 months from August through January have means above the aver- 

 age; the remaining six are all below. The month with the most 

 saturated atmosphere was January, 1883, the mean being 83. 67. The 

 least saturated atmosphere was during April, 1880, with a mean of 

 57.60. The mean saturation for spring is 69.77, for summer 71.54, 

 for autumn 72.41, for winter 73.21. The lowest observations were 

 17 on April 5th, 1881, and March 31st, 1884, at 2 p. m. 



RAIN-FALL. 



The mean annual rain-fall was 41.64 inches. The largest monthly 

 sum was 9.34 inches for August, 1880. One month, January, 1881, 

 is recorded as being entirely without rain. The heaviest single rain- 

 fall was 4.19 inches on April 22d, 1883, (see this Journal for 1883-84, 

 p. 83). March, with an average of 4.74, is the month of largest rain- 

 fall, December (4.30 inches), August (4.25 inches), and April (3.97 

 inches), coming next. There is no apparent division into wet and 

 dry seasons, the six months mentioned under humidity as being 

 most saturated have about the same average rain-fall as the other 

 six. Spring has an average of 11.25 inches, summer 11.58 inches, 

 autumn 8.08 inches, winter 10.76 inches. T' e monthly average is 

 3.47 inches. The range is from 34.50 inches in 1881, to 49.82 inches 

 in 1883, or 15.32 inches. 



PRESSURE. 



No comparisons can well be made between the barometric obser- 

 vations for the five years, as the first three were corrected for tem- 

 perature only, and the last two for temperature and an elevation of 

 500 feet. The true elevation is 514.47 feet. (This Journal for 

 1883-'84, p. 82). So far as the range is concerned, the mean annual 

 is 1.240 inches. The greatest annual range was 1.348 inches in 1881, 

 and 0.969 inches in 1880 was the lowest. January (1.095 inches) and 

 February (1.078 inches) are the months of greatest range. July, 

 August and September present the least range. January, February 

 and November are the months of highest barometer, and April and 

 June are the months of lowest barometer. As the mere statement 

 of the monthly range can give no idea of the number of changes or 

 barometric waves, these waves have been added up for the various 



