﻿KESEARCIT IN BRITISH WEST AFRICA. 



147 



on the average, whilst the " grass " temperature, that is, the minimum with the 

 thermometer at the ground level, is about 46°. 



These are the main characteristics of the climate of Southern Nigeria, but there 

 are enormous differences in the various regions ; and as it is with these differences 

 that we are more intimately concerned, it may be well to consider briefly the 

 range of these variations from a geographical aspect. 



The following tables have been prepared to illustrate graphically the main 

 features, so that I shall content myself by drawing attention only to the more 

 important characteristics : — 



Table A. — Annual rainfall at thirteen stations for the years 1905-1910. 



„ B. — Monthly record of rainfall at twenty-two stations for 1909 

 and 1910. 



„ C. — Analysis of the rainfall for 1910, showing on how many days in 

 each month at each station rain actually fell, and also the maximum 

 for any one day in each month at the individual stations. 



„ D. — Mean monthly humidity at the various stations in 1910. 



„ E. — Analysis of the monthly temperatures for the same stations 

 during 1910. 



Table A. 



Annual Rainfall in Southern Nigeria, (in inches). 



— 



Q 



pi 

 pi 



o 



m 



Forcados. 

 Sapele. 



o 



epl 



< 



Pi 

 O 





02 



o 

 bo 



h3 



133 



'8 



o 



a 



pq 



pi 



o 



O 

 02 



o 



d 

 >> 

 O 



1905 



16739 



167-75 





116-25 



83-88 



74-67 





65-11 



60-07 





47-52 



40-01 



38-61 



1906 



156-64 



142-26 



98-33 



106-69 



93-77 



87-08 



60-23 



74-76 



— 



58-34 



46-40 



47-95 



46-60 



1907 



129-68 



143-51 



— 



62-33 



70-38 



74-18 



55-82 



79-46 



48-46 



75-22 



38-26 



— 



43-81 



1908 



132-78 



160-36 



145-28 



118-52 



85-56 



— 



76-93 



69-98 



69-88 



70-02 



49-48 



51-43 



— 



1909 



150-24 



110-78 



149-25 



107-72 



— 



— 



85-28 



67-59 



91-36 



58-87 



62-26 



63-04 



— 



1910 



— 



— 



114-30 



105-24 



— 



— 



82-09 



69-43 



69-62 



53-06 



60-00 



— 



— 



Total 



736-73 



724-66 



507-16 



616-75 



333-59 



235-93 



360-35 



426-33 



339-39 



315-51 



303-92 



202-43 



129-02 



Mean 



147-34 



144-93 



126-79 



102-79 



83-39 



78-64 



72-07 



71-05 



67-87 



63-10 



50-65 



50-60 



43-00 



In this table (A) I have selected thirteen stations in which the records for the 

 years 1905-1910 are fairly complete and which are, at the same time, repre- 

 sentative of the various parts of the Colony. The mean for these years has been 

 taken as an index of the rainfall of the several stations, which have been 

 arranged in order of descending maxima. The most striking fact revealed by an 

 examination of this table is the enormous range in the mean annual rainfall, for 

 example, 147*34 inches at Calabar, and 43*00 inches at Oyo, while the maximum 

 25U0 C 2 



