Easter Rising in putting the rising off for only a day, although it greatly reduced the number of Volunteers who turned out. British Naval Intelligence had been aware of the arms shipment, Casement's return, and the Easter date for the rising through radio messages between Germany and its embassy in the United States that were intercepted by the Royal Navy and deciphered in Room 40 of the Admiralty. The information was passed to the Under-Secretary for Ireland, Sir Matthew Nathan, on 17 April, but without revealing its source, and Nathan was doubtful about its accuracy. When news reached Dublin of the capture
Earl of Drogheda of his brother-in-law, Henry Hamilton, 2nd Earl of Clanbrassil. In a feast of egotism, he built and named Henry Street, Moore Street, Earl Street, Of (or Off) Lane (now Henry Place, and an important escape route for the volunteers fleeing the GPO during the Easter Rising in 1916), and Drogheda Street (part of what is now O'Connell Street). The third Earl was succeeded by his grandson Henry, the fourth Earl. The latter died without surviving children at an early age and was succeeded by his younger brother, Edward, the fifth Earl, who had previously represented Dunleer in the Irish Parliament.