Meanwhile the Independent plot had been maturing. Towards the end of March an agent from O'Neill had appeared in London and managed, probably through Jones's recommendation, to communicate with the Council of State. The Council refused to receive him, but appointed a secret committee to hear what he had to say. The effect of their report was that the game was too dangerous, and the agent was ordered to leave London. Still if the game were too dangerous for the Council, Cromwell knew it was too good not to carry on a while longer, and there is little doubt that Jones received from him some secret instructions to that effect, which were communicated to Monk. It was absolutely necessary for the success of the coming expedition to Ireland that the Scotch and northern Royalists should be kept from joining hands with Ormonde, Clanrickarde, and Inchiquin, and so completing the investment of Dublin. The maimed and shattered forces of Monk and O'Neill were all that held them apart. O'Neill for some time had been in receipt of ammunition and supplies from the English officers, and Cromwell either now or not long afterwards was giving him regular pay; but this would no longer do. At the end of April O'Neill wrote a Latin letter to Monk urging him to press the Council once more to conclude a treaty on the terms his agent had unsuccessfully offered. But for this there was no time. A strong force was advancing upon O'Neill under Lord Castlehaven. It was a crisis in view of which Monk may or may not have had his instructions. At any rate he replied to O'Neill's letter asking what his terms were, and then after a short negotiation concluded with him on May 8th an armistice for three months, in order to give time for communication with England. The convention included a general defensive and offensive alliance between them against Ormonde for the time, provided always that no agreement was to be made by either with any one in arms against the Parliament. The effect was immediate. The Scots lost heart and ceased to press Monk, and he had leisure to forward O'Neill's new terms to England. How far he knew Cromwell was behind "the special friends and well-wishers to this service" who were advising him is uncertain. At any rate he was aware the Council must not know all, and that Cromwell was the man to address. So he sat down and wrote a long letter thanking the general for his many favours, and telling him the whole story of how his own desperate position and the necessity of keeping O'Neill from accepting Ormonde's terms had decided him to take the step he had. "I do not think fit," he continues, "to signify this to the Council of State, but do wholly refer the business to you either to make further use of it, or else to move it, or as you conceive most fit to be done. Since there was great necessity for me to do it, I hope it will beget no ill construction." And so he concludes beseeching Cromwell "to continue his good opinion" towards him.