PREFATORY NOTE. 



In view of the fact that the suggestion to use some of the water 

 power available at Aswan for the production of fertilizers has again 

 been revived the following may be of interest. 



This communication was made to the Cairo Scientific Society 

 on January 3, 1919, but owing to the temporary suspension of the Cairo 

 Scientific Journal it was not published. The paper was illustrated 

 by slides, mainly of the plant employed. These are not reproduced. 

 An Appendix containing the results of some experiments with nitro- 

 genous fertilizers on maize is added, as these results were referred to 

 and the photographs exhibited. 



F. H. 



