covered with a vegetation after man had migrated from the area, or that records 

 together with the statements of local villagers showed that the intermittent rain- 

 fall was due really to climatic oscillations over which man had no control. 



(e) This in spite of the more modern evidence upon the ground that the populations 

 — greatly swollen in numbers — were destroying the soil factors at an enhanced 

 rate, and that the rainfall fluctuations were of greater intensity; that no one, 

 scientist or African peasant, could predict the amounts of rainfall which would 

 occur in the year, or the times at which within certain periods, it would fall. 

 From the practical viewpoint of the administrator these are the points upon 

 which clarification is required and upon which concentration would appear 

 necessary. 



Desiccation is a much debated term in Africa and elsewhere in the world. It is 

 held to be due primarily to the over- utilisation of the vegetation covering of the soil 

 under which productivity is reduced, the decrease of water supplies in the springs, 

 streams, rivers and wells, the sinking of the water table in the soil strata, and de- 

 creases in the rainfall. It may be due to (a) the presence of neighbouring deserts and 

 sand penetration; (b) erosion in varying forms through over utilisation of the soil ; (c) 

 a combination of (a) and (b), accompanied usually by dry hot or cold winds. 



Lavauden (Les Forets du Sahara) does not use the word 'climate' in connection 

 with the process which he terms dessechment, by this meaning only the progressive 

 diminution of surface and subterranean water supplies. He does not discuss the rela- 

 tions existing between dis- afforestation and desiccation. Kennedy Shaw in consider- 

 ing this matter for Southern Libya says it is one of the present day increase of desert 

 conditions due entirely or largely to the acts of man'. In northern Nigeria desiccation 

 to whatever agency or series of agencies it may be subjected, is an accepted fact. Here 

 it may, it is suggested, be attributed to a combination of erosion sur place (for the more 

 level country) coupled with the lowering of the water table in the soil, the falling off of 

 the rainfall, and sand penetration from the Sahara. 



In some parts of Africa desiccation aided by sand penetration, may be due, in 

 part, to blown sand from drying off river banks or diminishing lakes. 



What is drought? An ordinary definition of 'drought' in the English language 

 would refer to months of dryness at periods when the ordinary average rainfall is re- 

 ceived. In Europe so far as records go, there appear to be years of wetter months fol- 

 lowed by years of drier ones, and we speak of 'drought' in its true sense — more or less 

 temporary climatic changes over which man can have little control. Can the word be 

 equally applied, or applied with its true significance, to the upsetting by man of 

 Nature's balance between the soil and its covering and the water supplies, with the re- 

 sulting dislocation in the regular average water supplies received in the rainfall and 

 from springs, streams, rivers and wells of the region? So far as we have knowledge and 

 evidence of the results attendent upon this intervention of man in Nature's balance it is 

 becoming more and more evident that periods of so-called drought will not be followed 

 by consistent wet periods, as has been sanguinely hoped in some quarters in connec- 

 tion with the major catastrophes facing man in certain parts of the world. Such hopes 

 are illusory. However the following proposition may be enunciated :- As a result of 



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