I see that on the 28th November 2009 you edited the entry for the Sennar Dam stating the information below.  

"It was built in 1925 by the British engineer, desert explorer and adventurer, Stephen "Roy" Sherlock, under the direction of Weetman Pearson."

You further go on to say that "Once completed, the dam was managed by Roy Sherlock until the 1970's."

Although I cannot contest the second statement, I cannot agree with the contention in the first sentence.  It may be that Stephen "Roy" Sherlock worked on the construction of the Sennar (Makwar) Dam.  However Pearson's Contract Agent was my grandfather, John Watson Gibson.   

The entry for the Sennar Dam gives a reference to:  O. L. Prowde, The Gezira Irrigation Scheme, Including the Sennar Dam on the Blue Nile, Minutes of Proceedings of the Institution of Civil Engineers, Vol. 222, p. 80 (1926).

Page 96 of that document contains the following:

The scheme was designed by Sir Murdoch MacDonald, M. Inst. C.E., Adviser to the Egyptian Ministry of Public Works.  He also exercised control over the carrying out of the work until his retirement from the Egyptian Government Service in 1921.
The consulting engineers were the late Sir A. L. Webb, M. Inst. C.E., from 1914 until his death in 1921, and Messrs. Coode, Fitzmaurice, Wilson, and Mitchell, from 1922 to the present date.
Colonel L. N. Cooper, M. Inst. C.E., was appointed resident engineer in 1914, followed by Mr. E. W. Buckley from 1914 to 1917. The Author has held that office from 1917 to the present date.
The contractors from 1919 to 1922 were the Sudan Construction  Company (Messrs. E. Alessandrini and G. S. Perry, M. Inst. C.E.).  From 1922 to the completion Messrs. S. Pearson and Son,  Ltd., carried out the work. Their director in charge was Sir Frederick T. Hopkinson, M. Inst. CE., the agent in charge being Mr. J. W. Gibson.
The sub-contractors for the supply and erection of the sluice steelwork were Messrs. Ransomes and Rapier, Ltd., of Ipswich, their engineer in charge being Mr. J. R. Russell.

On this basis I propose to amend the entry accordingly.

I would be very interested to know more about Stephen "Roy" Sherlock if you have it.