‘In my secret dispatch, of the 27th ultimo, I apprised your Lordship that I had had certain communications with an Officer of the French army, in respect to the discontent which prevailed against Marshal Soult. I have since had further communications with the same Officer, with the details of which I proceed to acquaint your Lordship.

‘Captain Argenton met me within the posts of the British army, between Coimbra and Aveiro on the night of the 6th instant, accompanied by Mons. Viana, in the presence of Lieut.-Colonel Bathurst. He informed me that the discontent had increased, and that there were a larger number of Officers who were determined to seize their General than when he had last seen me. He said, however, that they were divided into two parties, one discontented with Buonaparte himself, and determined to carry matters to extremities against him: the other, consisting of Loison, Laborde, and others (whom he had before mentioned as attached to the cause of the Emperor,) were dissatisfied with Soult’s conduct, particularly with an intention which he was supposed to entertain to declare himself King of Portugal; and that they were determined, if he should take that step, to seize him and to lead the army back into France, where it was understood the Emperor wished to see it.

‘Captain Argenton then urged me again to lose no time in pressing upon Soult, as the mode most likely to induce the more violent of the two parties to endeavour to accomplish their purpose. But he said that if my attack was likely to be delayed, it was desirable that I should endeavour to prevail upon some of the towns over which I was supposed to have influence, such as Coimbra, Aveiro, &c., to follow the example of Oporto, and petition Soult to take upon himself the government of the kingdom, as King; and that I even should write to him to urge the adoption of this measure.

‘In answer to this, I told him, that I certainly should make my attack as soon as it was in my power, but that I could not fix any day, nor state to him the plan of my operations; and that in respect to his propositions, regarding the measures to be adopted by me to induce Soult to declare himself King of Portugal, they were quite out of the question; that I could not risk the loss of the confidence of the people of Portugal by doing what he desired in respect to the people of Coimbra, Aveiro, &c., nor my own character by writing the letter which he proposed I should. I told him at the same time that I considered that, notwithstanding all that had passed between him and me, I had a full right to take what steps I pleased, even if the Officers of the French army should seize their General.

‘He then went away, and Mons. Viana returned with me to Coimbra, and confirmed all the statements which Captain Argenton had made of the discontent of the Officers of the army.

‘I heard no more of Captain Argenton till the 13th, the day after the capture of Oporto, on which day the original orders for the arrest and secret detention of Captain Argenton, Colonel Lafitte of the 18th dragoons, and Colonel Donadieu of the 47th regiment of infantry, were found among some papers sent to me by the police of the town; the order for the arrest of the first bearing date the 9th, and of the last two the 10th instant.

‘In a few hours afterwards, on the same day, Captain Argenton came into Oporto, and informed me that, on the night of the day he had returned from his last interview with me, he had been arrested, and his papers had been seized, among which had been found the three passports which I had given him. He said that he attributed his arrest to the General of Division Lefevre, a man of weak intellect, to whom he had formerly been aide de camp, and on whom he had endeavored to prevail, as he thought successfully, to join the party. General Lefevre had, however, informed Soult of all the circumstances, requiring only his promise that Argenton should not be injured, and should retain his commission and his military pretensions.

‘Soult examined him in presence of General Lefevre respecting his accomplices, but he declined to name any, and he was sent back to prison in charge of a Captain of Gendarmerie. This person prevailed upon him, with promises of pardon and indemnity to all concerned, to consent to tell Soult the names of his accomplices, which he did on the following night, notwithstanding, as he says himself, similar promises in his own favor, made to General Lefevre, had not been performed, and that as soon as he had named Colonels Lafitte and Donadieu, immediate orders were sent for their arrest and secret detention. They marched, in confinement, with the army from Oporto on the 12th, and on the 13th, at five o’clock in the morning, Captain Argenton made his escape, at the desire of Colonel Lafitte, from the party of Gendarmes in whose charge he was detained. He now declares that the conspiracy still exists, and that sooner or later it must burst forth and fall heavily upon the head of the usurper; and he talked of the war in Spain as being odious to the army and to the whole nation.

‘Captain Argenton expressed a desire to return secretly to France, and to bring to England his wife and family, she having, as he says, some property, to enable him to live in England till the arrival of better times in France.

‘I told him that I would send him to England when an opportunity should offer to apply for permission to go to France; and I shall have the honor of addressing him to your Lordship when the opportunity shall occur of sending him.