KKSBAKCH IN BKITISH \VE8T AFRICA. 



311. 



il 



1910, 



Geidam 









Oil 





0-51 



5-95 



7-07 



3-23 









Katagum 



— 



— 







0-25 



1-49 



0-95 



502 



7-45 



3-05 



— 



— 



— 



Maiduguri ... 



_ 



— 



— 



— 



2-80 



0-65 



6-64 



6-44 



3-00 



— 



— 



— 



Sokoto 



















3-54 



3-91 



6-51 



6-03 



3-06 



0-06 



— 



— 



Birnin Kebbi 















0-22 



2-32 



1-91 



7-78 



4-60 



8-21 



0-06 



— 



— 



Kano 













0-02 



0-98 



4-12 



8-10 



8-97 



4-62 



— 



— 



— 



Nafada 



— 



— 







0-43 



2'52 



4-73 



8-89 



13-04 



3-53 



0-10 



— 



— 



Yola 















2-36 



6-97 



10-19 



5-21 



8-06 



4-08 



1-80 



— 



— 



Bauchi 















0-98 



330 



4-73 



12-14 



8-98 



7-58 



1-15 



— 



— 



Keffi 



— 



— 



1-04 



1-72 



5-.H0 



5-28 



4-71 



13-98 



9-30 



3-10 



— 



— 



Lokoja 







1-03 



0-20 



4-45 



5-67 



8-07 



10-66 



5-98 



5-76 



3-61 



— 



— 



Baro 











0-15 



2-35 



5-00 



4-69 



15-20 



12-23 



4-15 



3-21 



— 



— 



Ibi 



— 



. — 



0-02 



4-39 



8-83 



5-56 



5-35 



11-24 



7-57 



6-67 



— 



— 



Iloriu 



— 



0-03 



1'18 



4-88 



5-97 



7-37 



6-60 



6-53 



14-71 



3-87 



— 



— 



Kontagora ... 











1-12 



0-44 



4-06 



4-17 



13-29 



16-91 



10-93 



2-09 



— 



— 



Zungeru 







— 



0-83 



1-15 



669 



6-54 



7-09 



19-27 



10-82 



2-05 



— 



— 



Zaria 



— 



— 



— 



2-17 



3-78 



4-95 



11-28 



17-73 



13-08 



0-81 



-- 



— 



Ankpa 



1-34 



— 



1-02 



5-65 



10-04 



5-64 



9-38 



11-42 



5-GO 



6-31 



— 



0-04 



In Table B is given the monthly rainfall for eighteen stations for the years 

 1909 and 1910, and as these stations are scattered over the territory, it is 

 possible to compare not only the extremes, but also the intervening portions of 

 the country. The arrangement adopted is that of ascending annual maxima. 



It will be seen from Table A that, although there was a great difference in 

 the amount of rain which fell during these two years, the total for each station 

 bears roughly the same proportion to the total for the colony. The curve of 

 rainfall has only one maximum, and that occurs in July and August, which 

 months are therefore the centre of the rainy season. A rainfall of one inch 

 or under is practically negligible, so that, with very few exceptions (which will 

 be referred to later), November, December, January and February constitute 

 the height of the dry season. 



Although July and August on one side, and December and January on the 

 other, are the centres of the wet and dry seasons respectively, the duration of 

 these seasons varies very markedly in different regions ; e.g., at Geidam, in 1910, 

 the dry season might be said to extend from October to June, while in the same 

 year at Ankpa the dry season can be reckoned only from November to March. 



It will be seen from the tables that, in spite of the diff'erence in the rainfall in 

 1909 and 1910, the stations are arranged in certain well-defined groups, e.f/., (1) 

 Geidam, Katagum, Birnin-Kebbi, Sokoto and Maiduguri ; (2) Nafada, Bauchi, 

 Yola, Keffi and Kano ; (3) Ibi and Baro ; (4) Zaria, Zungeru and Kontagora ; 

 (5) Lokoja, Ilorin and Ankpa ; and that these groups of ascending rainfall are 

 disposed in order from north to south. 



In the northern stations, the dry season reaches its maximum, and may be said 

 to extend from October to April, but at the same time, the monthly rainfall is 

 never very great. The length of the dry season diminishes in the various groups, 

 until (5) is reached ; for example, at Ilorin, in 1909, rain fell during every 

 month, and at Ankpa, in both 1909 and 1910, the only months in which there 



22036 C 



