Copy letter from Robert William Frederick Harrison, to Lord Rayleigh [John William Strutt], President, Royal Society 'Water supply of Cairo - letter from British Agency at Cairo dated April 1, 1907 This matter must presumably come before the Council at their meeting on the 25th, but the President may wish to make preliminary enquiries. Will the President kindly return the letter to this office. It has been acknowledged. RWFH'. 12 April 1907