To add to the public dissatisfaction the Duke of York, the heir presumptive to the throne, openly espoused the cause of Catholicism. Strong measures were consequently adopted to remove him from his post, as admiral of the navy, and eventually to exclude him from the throne. The violent factions, and fierce criminations and recriminations to which these measures gave rise kept the people in a state of feverish excitement. In the midst of these wild alarms a pretended popish plot was reported to have been discovered, which received universal credence. The design of this plot was said to be to destroy parliament and assassinate the king. A secret Catholic faction was supposed to exist in the nation, the object of which was to restore the authority of the pope; and circumstances lending credibility to the supposition, the most intense excitement seized the public mind. Parliament was terrific in its denunciations, and the people clamorous for vengeance. Lords were arrested, priests hung, the Duke of York fled from the country in terror, the Earl of Stafford was beheaded, and the king, filled with consternation, yielded to the popular demand the Habeas Corpus act, to avert the storm that was muttering destruction over his head. Fortified with this new safeguard to public freedom, the people became tranquil once more; but the king perceiving the formidable obstacle which parliament obtruded in the way of his acquisition of despotic power, resolved to get rid of it by making it the instrument of its own destruction. After having assembled it several times for this purpose, and finding it inflexibly opposed to his measures, he determined to dispense with it altogether, and to substitute his prerogatives in the place of its authority. In order to reduce the corporations to an absolute dependence on his will, he employed with as much baseness as tyranny, intimidations to induce them to surrender their charters, so that they might be remodelled in accordance with the claims of the absolute power of his prerogatives. In order to deplete the ranks of non-Catholics, he had recourse to gross and unfounded charges of plots and conspiracies. Lord Shaftsbury, the author of the Habeas Corpus act, was arrested, imprisoned in the Tower and tried for high treason; but acquitted. Dungeons were overcrowded with subjects against whom no allegation laid, except that of love of liberty and opposition to tyranny. But while he was wading through the innocent blood of his subjects to a crown of unlimited monarchy, some desperate spirits were secretly concocting a plot to arrest his atrocious career by the deplorable means of the assassin's dagger. This unsuccessful conspiracy, known as the Rhyhouse plot, which could not escape the omniscient eye of the Catholic machinery, was, of course, discovered before it had matured its plans, and only gave the king a plausible pretence for gratifying his malignancy against the ablest advocates of constitutional liberty.