The Castle of Dublin, by which the capital was commanded, contained arms for ten thousand men, with thirty-five pieces of cannon, and a proportionable quantity of ammunition; yet was this important place guarded, and that too without any care, by no greater force than fifty men.

Maguire and More were already in town with a numerous band of their partisans; others were expected that night and next morning they were to enter upon what they esteemed the easiest of all enterprises, the surprisal of the castle.

O'Conolly, an Irishman, but a Protestant, betrayed the conspiracy to Parsons.[*] The justices and council fled immediately for safety into the castle, and reenforced the guards.

The alarm was conveyed to the city, and all the Protestants prepared for defence.

More escaped; Maguire was taken; and Mahone, one of the conspirators, being likewise seized, first discovered to the justices the project of a general insurrection, and redoubled the apprehensions which already were universally diffused throughout Dublin.[**] But though O'Conolly's discovery saved the castle from a surprise, the confession extorted from Mahone came too late to prevent the intended insurrection.