In 1663 a certain Thomas Ibson attempted to come to an agreement with the postmasters on the Holyhead road. He wished to have the privilege of horsing travellers and made an offer to the postmasters to take charge of the post houses if they would allow him to proceed. He told them that they should make an attempt to have their salaries restored to their old value by Bishop, who had raised so much from them by fines and lowering their salaries. The Postmaster-General told his deputies that if they dared to treat with the "would-be" interloper he would dismiss them, and the whole thing fell through.[763] At the same time a warrant was issued by the Council to mayors and other officials to search for and apprehend all persons carrying letters for hire, without licence from the Postmaster-General.[764] Nevertheless interloping did not cease, as is shown by the complaints from the postmasters.[765] [763] _Cal. S. P. D._, 1663-64, pp. 8, 18. [764] _Ibid._, 1663-64, p. 145. [765] _Ibid._, 1663-64, p. 402. In the proclamation following the appointment of O'Neale as Postmaster-General in 1663, it was ordered that no one should dare to detain or open a letter not addressed to himself unless under a warrant from one of the Secretaries of State. An exception was made in the case of letters carried by unauthorized persons. Such letters should be seized and sent to the Privy Council. In later proclamations it was provided that they might be sent also to one of the Secretaries of State in order that the persons sending or conveying them might be punished.[766] [766] _Rep. Com._, 1844, xiv, 601, app., p. 88 (61). After Lord Arlington's appointment as Postmaster-General, he addressed a petition to the Duke of York complaining "that carriers, proprietors of stage coaches and others take upon themselves to collect letters to an incredible number and on some stages double what the post brings." On account of this he pointed out to His Royal Highness that a considerable part of his revenue was lost. This was quite true since the Post Office had ceased to be farmed and the whole net revenue went to the Duke.[767] This was followed the same year by a proclamation forbidding any one to collect or carry letters without the authority of the Postmasters-General. Carriers were forbidden to convey any letters which were not on matters relating to goods in their carts. Shipmasters must carry no letters beyond the first stage after their arrival in England with the exception of the letters of merchants and owners. Searchers were appointed to see that the proclamation was enforced.[768] It was even proposed to suppress all hackney coaches, the principal reason given being that they decreased the value of the Duke's monopoly by carrying multitudes of letters.[769] [767] _Cal. S. P. D._, 1668-69, p. 285. [768] _Cal. S. P. D._, 1668-69, p. 376. [769] _Ibid._, 1672-73, p. 64.