Having secretly procured an arquebuss and ammunition, he now only awaited a favourable moment for the enterprise. This soon occurred. It being rumoured one night in the Tower, that the queen was about to proceed by water to Whitehall on the following morning, he determined to station himself at some point on the line of road, whence he could take deliberate aim at her. On inquiring further, he ascertained that the royal train would cross the drawbridge leading from the south of the Byward Tower to the wharf, and embark at the stairs. Being personally known to several officers of the guard, he thought he should have no difficulty in obtaining admittance to Saint Thomas’s Tower, which, while it commanded the drawbridge, and was within shot, was yet sufficiently distant not to excite suspicion. Accordingly, at an early hour, on the next day, he repaired thither, wrapped in a cloak, beneath which he carried the implement of his treasonable intent. As he anticipated, he readily procured admission, and, under pretence of viewing the passage of the royal train, was allowed a place at a narrow loophole in the upper story of one of the western turrets. Most of the guard being required on the summit of the fortification, Underhill was left alone in the small chamber. Loud shouts, and the discharge of artillery from the ramparts of the fortress, as well as from the roofs of the different towers, proclaimed that Mary had set forth. A few embers were burning on the hearth in the chamber occupied by the enthusiast. With these he lighted his tow-match, and offering up a prayer for the success of his project, held himself in readiness for its execution. Unconscious of the impending danger, Mary took her way towards the By-ward Tower. She was attended by a numerous retinue of nobles and gentlemen. Near her walked one of her councillors, Sir Henry Bedingfeld, in whom she placed the utmost trust, and whose attachment to her had been often approved in the reigns of her father and brother, as well as during the late usurpation of Lady Jane Grey. Sir Henry was a grave-looking, dignified personage, somewhat stricken in years. He was attired in a robe of black velvet, of the fashion of Henry the Eighth’s time, and his beard was trimmed in the same bygone mode. The venerable knight walked bare-headed, and carried a long staff, tipped with gold.