Martha. The group met on 20 May 1604 at the Duck and Drake inn, in the fashionable Strand district of London. After the meeting they swore an oath of secrecy on a prayer book and celebrated Mass in another room with Father John Gerard, who was ignorant of their purpose. From these early meetings, according to biographer Mark Nicholls, John exhibited "little sign of doubt or scruple thereafter". He remained close to the heart of the conspiracy, moving his family to Lapworth in Warwickshire, and stabling horses there. By March 1605 Christopher had joined the conspiracy as well, but in October that year, as the plan was nearing its culmination, its existence was revealed to the authorities by an anonymous letter delivered to William Parker, 4th Baron Monteagle, warning him to stay away from Parliament. Uncertain of its meaning Monteagle delivered the letter to the English Secretary of State, Robert Cecil, 1st Earl of Salisbury. Monteagle's servant was closely related to Christopher's wife, Margaret, and thus the plotters soon became aware of its existence. Catesby, by then at White Webbs near Enfield Chase with the Wright brothers, decided that the letter did not constitute a sufficiently serious threat to the scheme, and he decided to forge ahead. On 4 November Percy visited his patron, Henry Percy, 9th Earl of Northumberland, to see if he could discern what rumours surrounded the letter. He returned to London and assured John, Thomas Wintour and Robert Keyes that they had nothing to be concerned about. That same evening John probably set off for the Midlands with Catesby and his servant Thomas Bates, while the others moved into their positions, ready for the planned explosion the following day. At about midnight the authorities made a search of the House of Lords, and in the chamber's undercroft they discovered and arrested Fawkes, who was guarding the gunpowder the conspirators had placed there. As news of Fawkes's capture spread, particularly through the great houses of the Strand, Christopher deduced what had occurred and went to Thomas Wintour at the Duck and Drake inn, exclaiming "the matter is discovered". Wintour ordered him to verify the news, and on confirming that the government were seeking Thomas Percy (for whom Fawkes, using the alias "John Johnson", claimed to be working), ordered him to alert Percy. Christopher and Percy left London together, heading for Dunstable. With the group mostly reintegrated, they