Mr. Froude, after a perusal of the letters of Downshire's friend, and other documents, states that a priest named O'Coigly or Quigley 'had visited Paris in 1797, returned to Dublin, and had been with Lord Edward Fitzgerald at Leinster House; that he was now going back to Paris, and Arthur O'Connor determined to go in his company.[39] Their mission, though ostensibly for presenting an address from the London corresponding society of United Irishmen to the French Government, was really for the double purpose of urging upon it the prompt despatch of an invading fleet to Ireland, and of deposing the Irish envoy, Lewins, who, instead of Turner, had begun to be suspected. Mr. Lawless, afterwards Lord Cloncurry, invited O'Coigly to dinner in London; and it was on this occasion that O'Connor met the priest for the first time. O'Coigly, under the name of Captain Jones, with Allen[40] seemingly as his servant, and Leary, left London for Margate, on their mission of mystery. O'Connor travelled by another route to Margate, took the name of Colonel Morris, and was accompanied by Binns. On the following day, at the King's Head Inn, Margate, all the party were arrested by two Bow Street officers. O'Coigly and O'Connor had dined at Lawless's lodgings more than once; and here, though not necessarily with his knowledge, the travelling arrangements seem to have been made. Whether Turner was a guest does not appear; but he was certainly in London at this time, and as one of the Executive Committee is likely to have been invited. Presently it will be shown that from this quarter came all the information which enabled Pitt to seize O'Connor and O'Coigly at Margate en route to France, although, to elude observation, they had journeyed by different roads. The prisoners, meanwhile, were removed to London, examined before the Privy Council, and then transmitted to Maidstone Jail to await their trial. The source of the information which caused these historic arrests on February 27, 1798, has hitherto remained a mystery. Father O'Coigly, while in jail, wrote some letters, in which he failed to avow his share in the conspiracy, but admitted to have made a previous visit to Cuxhaven. This was part of the city of Hamburg. Turner, in addition to being the official agent of the United Irishmen at Hamburg, was an old Dundalk acquaintance of O'Coigly's, and no doubt was promptly hailed by the country priest.

Turner and O'Coigly are mentioned in Hughes's information. They belonged to the same district organisation. After describing Teeling, Turner and Lowry working in concert in 1797, Hughes adds that priest Quigly or O'Coigly introduced him at that time to Baily and Binns.[41] The paper revealed by Mr. Froude, now shown to be Turner's, and other letters from the same hand in the 'Castlereagh Papers,' show that the writer always felt a strong dislike to work with the 'Papists,' especially priests. 'Casey, the red-faced, designing Dublin priest,' was one of the leading men he met in Dublin, and whose 'prudence or cowardice' disgusted him. Immediately after O'Coigly's return to London we find the authorities on his track. The priest himself refers to an abortive attempt to arrest him by night at Piccadilly.[42] Mr. Froude, dealing with this case, does not seem to have suspected that the arrival in London of Downshire's friend, at the time of the arrests at Margate, was other than accidental. Yet clearly it was business of no ordinary moment which brought him back to London at this time. It will be remembered that, panic-stricken and fearing death from the assassin's knife, he had returned to Hamburg in October 1797, ere an answer came from Pitt to the proposition of betrayal conveyed by Lord Downshire.

After describing the arrest at Margate of Father O'Coigly, O'Connor, and Binns, Mr. Froude writes:—

It may be observed here—en parenthÈse—that Downshire must have felt conflicting emotions when called upon to communicate information which might bring Lord Edward to the block. His father had married the sister of James, Duke of Leinster; Lord Edward was, therefore, the first cousin of Lord Downshire.

One of the most truthful chapters of the laudatory life of Reynolds, the informer,[48] is that aiming to show that he could not have been the spy who caused the arrests at Margate. But the biographer is unable to offer any suggestion as to who that agent was—so carefully veiled from Reynolds, one of their own confidential prompters, was the part played by Turner in that episode.

The information which led to the arrest of O'Connor, O'Coigly, and his companion cannot have come from Ireland, because in the 'Book of Secret Service Monies expended in the Detection of Treasonable Conspiracies' no entry appears connected with the above incident, unless 'Dutton's Expenses going to England to attend Quigly's Trial,' and where he had merely to swear to the priest's handwriting. For his courage in doing this—having once seen him sign a lottery ticket at Dundalk—50l. is paid to 'Dutton on June 12, 1798.' The names of Newell and Murdoch certainly appear in the 'Secret Service Money' book about that time; but it is clear from Newell's narrative—doubtless a genuine and frank confession—that neither he nor Murdoch had any hand in tracing the movements of O'Coigly and O'Connor.

Lord Castlereagh was now acting for Pelham as Chief Secretary for Ireland. On July 25, 1798, a secret letter—printed in the 'Castlereagh Papers'—is addressed to him from the Home Office:—

Some of the letters of 'Lord Downshire's friend,' not being forthcoming in the official archives, Mr. Froude assumed that they had been destroyed; but, however masked, they are recognisable in the 'Castlereagh Correspondence.' Several anonymous papers, furnishing information of the movements of the United Irishmen about Hamburg and elsewhere, crop up in that book, having been enclosed from Whitehall for the guidance of Dublin Castle. One of these letters makes special reference to information already sent to Lord Downshire.[54]

Another long letter of the same batch will be found the first placed in the second volume of Castlereagh, though an examination of it shows that it belongs to the middle of the previous volume. Detailed reference is made to Father O'Coigly's mission and movements, both in France and in London. One is struck by the accuracy of its information regarding the Ulster United Irishmen, of whom Turner was one. Of MacMahon, who travelled to Paris with O'Coigly, we learn that, 'tired of politics, especially those of France, he is to write to Citoyen Jean Thomas,[55] À la poste restante À Hamburg, whom he looks on as a good patriot.'[56] It will be remembered that a similar phrase occurs in the letter of Downshire's friend, printed by Froude, i.e. Rowan had 'professed himself sick of politics.' Again, 'I found Maitland and Stewart, of Acton, both heartily sick of politics.'

How to hang O'Coigly was now the difficulty. The Government knew—from somebody who had worked with him—that he was deep in the treason; but nothing could persuade the informer to prosecute him openly.

On April 11, 1798, Wickham writes from Whitehall:—

The secret adviser who, as Portland said, 'should be detained,' worked his brain until at length a man, hailing from a place suspiciously familiar to Turner, is sent for to swear to the point. Samuel Turner, formerly of Newry, had intimate knowledge of every man in the place. One Frederick Dutton, described as 'of Newry,' was now subpoenaed by the Crown to swear to O'Coigly's handwriting in a letter addressed to Lord Edward Fitzgerald. 'He claimed to have seen Coigly write his name for the purpose of getting a watch raffled which belonged to a poor man under sentence of death.' Dutton had been a dismissed servant and had kept a public-house at Newry without a licence.[58]

Turner—it seems absurd to doubt the identity—got back to London on Tuesday, May 15, 1798. What secret help he gave to the law officers can only be inferred, for they pledged themselves that he should never be asked to come forward publicly. Though O'Connor, O'Coigly, and Binns[59] were arrested on March 1, their trials did not take place till late in May 1798. The Duke of Norfolk, Lords Moira, Suffolk, Oxford, John Russell, and Thanet, Fox, Sheridan, Whitbread, Erskine, Grattan, all testified to O'Connor's character. All the prisoners were acquitted, except the priest, notwithstanding that Lord Cloncurry paid a counsel to defend him. He was hanged on Penenden Heath, June 7, 1798. Judge Buller had leant heavily on O'Coigly in his charge.

Lord Holland adds that when the Judge was descanting on the mildness and clemency of the Administration, O'Coigly quietly took a pinch of snuff and said 'Ahem!'

When no evidence was produced in court which could legally ensure a verdict against O'Coigly, it seems reasonable to assume from the tone of the law officers and the Judge that they possessed some secret knowledge of his guilt, for in point of fact, though O'Coigly declared his innocence, he was deeply pledged to the conspiracy.

'O'Connor was leaving the court in triumph,' writes Mr. Froude, 'but the Government knew their man too well to let him go so easily. He was at once re-arrested on another charge, and was restored to his old quarters in Dublin Castle.'[62] From whom the fatal whisper came does not appear, but the sequel seems to leave no doubt that to Turner it was due. MacMahon and other prominent rebels were Presbyterian clergymen of Ulster. It was an object now with those who desired the collapse of the conspiracy to detach the Presbyterian party from the 'Papists.' Binns was a staunch Presbyterian rebel, a colleague of O'Coigly. In a letter dated Philadelphia, 1843, Binns, addressing Dr. Madden, states that great efforts were used to try and persuade O'Coigly to implicate him, 'offering Mr. Coigly his life if he would criminate me agreeable to the instructions of the Government, which proposal he indignantly refused to accede to. Though heavily ironed, he pushed the gentlemen out of his cell, when he there lay under sentence of death.'

We have seen that when severely tried he resorted to snuff. He had other small consolations. Even in his irons he talked irony. One of several letters of protest addressed by the priest to Portland, shortly before his death, tells him that he is 'one of his Grace's envoys to the other world, charged with tidings of his mild and merciful administration.'

As O'Coigly's memory has been all but beatified as a martyr's, it is due to the interests of historic truth to add—especially after the remarks of Lord Holland—the following from a letter written by Arthur O'Connor in 1842:—

O'Connor's promised work, however, never appeared.

As regards Dutton, the witness who swore to O'Coigly's handwriting, his subsequent career was cast on a spot also frequented by Turner.[63] He is found at Cuxhaven, not very far from Hamburg, and, until 1840, holding office in its postal and diplomatic departments, and the husband of a lady well connected.[64] Cuxhaven, as gazetteers record, was from 1795 a place of the utmost importance for the maintenance of intercourse between England and the Continent.