i^i /'Xr YPT1A S A iJrIU C t L TURE. 



During the months of August, September, and October, 

 when the basins are filled, the average percentage of organic 

 matter in the mud amounts to between 8 and 9^ while 

 during the three months of May, June, and July, when 

 the Nile is at its lowest, it amounts to as much as 20^ or 

 more. That is to say, in respect of organic matter the 

 suspended matter of the red water is poorer than that of 

 any other time of the year. This is in accordance with 

 what would be expected. When the Nile is low the small 

 volume of water becomes contaminated with organic matter 

 of various kinds but with the rise of the river the percentage 

 of organic matter shows a rapid decline. Simultaneous 

 therefore with the fall of the river we obtain an increase 

 in the percentage of organic matter which reaches its 

 maximum in June when the water contains a considerable 

 amount of green vegetable matter which has accumulated 

 chiefly in the region where the Gazelle river joins the 

 White Nile and which is now brought down by first rains. 



It is a matter of great interest to ascertain the richness 

 of the suspended matter in nitrogen as the great differences 

 of opinion which have arisen as to the general composition 

 of the suspended matter of the Nile water have generally 

 centred on this point. From the very nature of things 

 we should not anticipate a very high nitrogen content. 

 The organic matter has been transported an enormous 

 distance in water at a comparatively high temperature 

 where all the necessary conditions exist for its decomposi- 

 tion and decay and the consequent removal of a large 

 portion of its valuable nitrogen. 



During the months of low Nile, the percentage of 



