Relative Humidity. 



275 



Humidity with reference to the Moon's Age. — The following means of groups indicate a minimum of hu- 

 midity about four days before full Moon, and a maximum about four days before new Moon. 



12 days till 18 days, Full Moon, 0-845 



15 22 ... 0-857 



19 26 ... 0-859 



23 29 ... 0-864 



27 days till 3 days. New Moon, 0-851 



7 ... 0-842 



4 11 ... 0-851 



8 14 ... 0-844 



Humidity with reference to the Moon's Declination. — The following means of groups indicate a maximum 

 of humidity about four days before the Moon attains its greatest north declination, and a minimum about four 

 days before it attains its greatest south declination. 



25 days till 3 days, Moon farthest North, 0-847 



6 ... 0-846 



4 10 ... 0-838 



7 13 ... 0-844 



11 days till 17 days. Moon farthest South, 0-849 



14 20 ... ' 0-842 



18 24 ... 0-857 



21 27 ... 0-861 



TABLE XIV. — Hourly Means of the Relative Humidity for each Month and Quarter in 1843, 



Saturation being = 1. 



Period. 



ISi. 



20''. 



221'. 



O''. 



21'. 



41'. 



61'. 



81". 



101'. 



Mean. 



Kange. 



January 



0-858 



0-869 



0-850 



0-814 



0-811 



0^837 



0-860 



0-841 



0-842 



0-844 



0-058 



February 



•899 



•889 



•863 



•815 



-811 



•830 



•876 



•891 



-920 



•877 



-109 



March 



•914 



•908 



•860 



•803 



•766 



•758 



•813 



•881 



-886 



•857 



•156 



April 



•895 



•855 



•774 



•708 



•692 



•694 



•757 



•839 



•850 



•807 



•203 



May 



•930 



•883 



•811 



•766 



•735 



•759 



•768 



•840 



•903 



-845 



•195 



June 



•873 



•821 



•766 



•727 



•737 



•720 



•740 



•768 



•857 



•800 



•153 



July 



•908 



•849 



•768 



•740 



•718 



•723 



•779 



•838 



•881 



•824 



•190 



August 



•947 



•907 



•823 



•764 



•720 



•711 



•775 



•887 



•930 



•857 



•236 



September 



•936 



•933 



•850 



•746 



•693 



•676 



•771 



•893 



•931 



•852 



■260 



October 



•910 



•916 



•837 



•783 



•746 



•766 



•848 



•890 



•891 



•857 



-170 



November 



•927 



•929 



•909 



•846 



•838 



•845 



•906 



•924 



•923 



•902 



•091 



December 



•886 



•886 



•844 



•860 



•848 



•866 



•877 



-875 



•881 



•873 



•042 



Spring 



•913 



•882 



•815 



•759 



•731 



•737 



•779 



-853 



•880 



•836 



•182 



Summer 



•909 



•859 



•786 



•744 



•725 



•718 



•765 



-831 



-889 



•827 



•191 



Autumn 



•924 



•926 



•865 



•792 



•759 



•762 



•842 



-902 



-915 



•870 



•167 



Winter 



•881 



•881 



•852 



•830 



•823 



•844 



•871 



•869 



•881 



•865 



•058 



The Year 



•907 



•887 



•830 



•781 



•760 



•765 



•814 



■864 



•891 



•850 



•147 



Table XIV. has been formed from Tables III. and VIII. by means of the formula given after Table XII. 



Diurnal Variation of the Relative Humidity. — The maximum humidity occurs between 9 p.m. and 5 a.m. 

 The minimum occurs as early as 10^ 30"" a.m. in December, and as late as 2^ 30™ in Marcli and September. 

 The progression is regular in each month, with the exceptions of June and December ; a secondary maximum 

 occurs in the former at 1'' 10™ p.m., and in the latter at ll** 10™ a.m., the minima occurring two hours before 

 and after. The following are the periods of minima for the four meteorological seasons, and also for the four 

 astronomical seasons : — 



Meteorological Seasons. 

 Spring, Ih 40™ p.m. 

 Summer, 2^ 30™ p.m. 

 Autumn, 2^ 10™ p.m. 

 Winter, O'^ 30™ p.m. 



Astronomical Seasons. 

 Spring, 2^ 0™ p.m. Makerstoun mean time. 



Summer, l^* 25™ p.m 



Autumn, 2^ 20™ p.m 



Winter, 0'' 50™ p.m 



The year, 1^ 50™. 



