NO. 17.] 



TEMPERATURE OF THE AIR. 



489 



The columns 1, 2 and 3 show a very decided annual period (PI. III. 

 1 mm. = 1° C). The interdiurnal variability is greatest in the wintertime; 

 the maximum lies in February, and is lowest in July. The numbers form 

 a very regular curve. The mean rising for the year is a little lower than 

 the falling. The time during which the temperature is rising, is longer than 

 its time of falling; it rises more slowly than it falls. The means for the 

 3'^ column are 



Winter Spring Summer Autumn 



+ 3°-85 ± 2°-83 + 0°-83 + 3°-27 



The next Table gives the mean number of cases (days) in which the 

 mean diurnal temperature has changed from one day to the next from 0° 

 to 0-°9, from 1 to l-°9, etc. 



o o 



0-1 



o o 



1-2 



o o 



2-3 



O O 



3-4 



O O 



4-5 



O O 



5-6 



O O 



6-7 



O O 



7-8 



O O 



8-9 



9-10 



10-11 



11-12 



12-13 



13-14 



15-16 



16-17 



17-18 



21-22 



Jan. . 

 Febr. . 

 Mar. . 

 Apr. . 

 May . 

 June . 

 July . 

 Aug. . 

 Sept. . 

 Oct. . 

 Nov. . 

 Dec. . 



Winter 

 Spring . 

 Summer 

 Autumn 



Year 



8-7 



5-7 



5-3 



7-0 



11-3 



18'0 



26-0 



22-0 



8'5 



4-8 



4-7 



4-7 



64 



7-9 



22-0 



60 



10-6 



4-7 

 3-7 

 6-0 

 7-3 

 8-3 

 8'0 

 50 

 4-5 

 5-5 

 60 

 5-3 

 5-7 



4-4 

 7-2 

 5-8 

 56 



5-8 



3-3 



3'7 

 3-7 

 4-7 

 4-0 

 2-3 



2'5 

 8-0 

 7-2 

 4-7 

 4-3 



3-8 

 4-1 

 1-6 

 6-6 



4-0 



3-3 



2-7 

 3-7 

 3-3 

 2-7 

 1-0 



1-5 

 3-5 



2-4 

 4-0 

 60 



4-0 

 3-2 

 0-8 

 3-3 



3-8 



2-7 

 2-7 

 2-0 

 3-7 

 1-3 

 0-7 



0-5 

 20 

 20 

 30 

 2-3 



2-6 

 2-3 

 04 



2-7 



2-0 



3-3 

 1-7 



2-7 

 2-3 

 2-3 



0-5 

 28 

 2-3 

 3-3 



2-8 

 2-4 



1'8 

 1-8 



1-0 

 1-3 

 1-3 

 0-7 

 0-7 



1-0 

 2-4 

 1-3 

 1-0 



l-l 

 0-9 



1-6 

 0-9 



1-7 

 1-3 



2-0 

 0-3 



0-5 

 20 

 20 

 1-0 



1-3 



0-8 



1-5 



0-7 



1-3 

 1-3 



2-0 

 0-3 



0-8 

 0-3 

 10 



0-3 

 10 

 10 



0-3 



0-5 



0-8 

 10 

 1-0 



1-0 

 0-3 



0-3 



Per month. 



1-2 



0-8 



0-4 

 0-6 



0'8 

 0-4 



0-8 

 0-5 



0-4 

 0-1 



0-1 



0-7 

 1-0 

 1-0 

 0-3 



0-3 



0-6 

 0-4 



0-1 

 0-3 



0-3 



0-4 

 0-3 

 0'3 



0-1 



0'2 

 0-1 



01 



0-3 



0-3 



0-02 



01 

 0-02 



0-3 



01 



01 

 005 



0-3 



0-3 



01 



01 



002 



0-02 



The smallest interdiurnal variations are of the greatest frequency. In 

 winter the variation reaches 21°. This was the case from the 20"' to the 21^' 

 February, 1896, when the mean diurnal temperature rose 21'° 8, from — 40"°8 



