It has never been hinted that M. Bertin suspected the paternity of his heir. Through life the conduct of Madame Bertin was irreproachable and above all suspicion.
In the infancy and boyhood of Louis, his father strove by systematic oppression, and by cutting neglect, to degrade, mortify, and break the spirit of the poor little fellow: on all occasions giving the place of honour, and the whole of his affection, to his second son. As his manhood approached, his father proposed to him the profession of the law, but as he, weary of his unhappy home, displayed an inclination for the army, open war was at once declared by his father against him. To more than one abbé did the young man in his misery appeal for intercession with his tyrannical parent; but such appeals only made matters worse, and the Counsellor became so furious in his wrath, that he made preparations to seclude Louis in some strong vault or cellar of his mansion.
The Marquis having discovered the residence of a young woman who was the mistress of his father, paid her a secret visit, told her the story of his unhappy life and domestic persecution; and, as his own mother seemed powerless in the matter, on his knees sought her interest in his behalf. She would seem to have been touched by the appeal; and rated the Counsellor soundly for his unnatural conduct, threatening him with the loss of her affection "if M. Louis were not left to his own inclination in the choice of a profession."
In the hope, perhaps, that some English or Prussian bullet might rid him of a son whom he hated so cordially, Bertin permitted the Marquis to join the Regiment de Noailles (or 54th Cavalry of the Line, commanded by the Comte d'Ayen, nephew of Marshal Noailles) as a cadet or volunteer; but, according to the system then pursued in the French service, he could receive no pay or emolument, even while campaigning in Flanders and Germany. After fourteen months of this probation, however, he was gazetted to a cornetcy in the Regiment de Maine, and at sixteen years of age became captain of a troop in the 40th Cavalry, or Dragoons of St. Jal, commanded by Brigadier the Comte de St. Jal;* his boyish spirit and bravery (not to mention his rank) having even then attracted the attention of Comte d'Argenson, who was prime minister of France from 1743 to 1757. The Count prevailed upon Louis the Fifteenth to make the Marquis a Chevalier of the Royal Order, and bestow upon him a special pension, in lieu of the wretched pittance allowed him by his father.
* Liste Historique de toutes les troupe au Service de France.
This early success in camp and at court seemed to inflame the resentment of the Counsellor, who now began to affirm that the Marquis was not his son, but a changeling, or impostor, substituted by the nurse for his first child, who, he declared, had died while under her charge; but, as this story could be in no way sustained, M. Bertin changed his tactics, and resolved to get rid of his eldest son by—poison!
A fever with which Fratteaux was seized about this time, favoured the infamous idea; and his father, who visited him with an air of concern, contrived to give him, in his medicine, a dose of some deadly drug which he called an infusion of bark. It nearly proved fatal, and would inevitably have done so, but for the prompt arrival of the apothecary who had furnished it, and who, suspecting foul play when summoned by the Marquis, brought with him a powerful antidote.
The Counsellor, who was immensely rich, now suborned some worthless fellows, among whom was an Italian (name unknown), to swear that Fratteaux meditated a parricidal design against his life; "that the Marquis, having a quarrel with his father, drew his sword, and would have killed him but for the interposition of the father of the Italian, who received the thrust, and died of it."
This deposition enabled Bertin to purchase a lettre de cachet, by virtue of which he had his son arrested, and thrust into a monastery near Bordeaux, where he was treated as a prisoner. Though for the crime of attempted parricide he might have been broken alive on the wheel by the then existing laws of France.
Through the great influence of Bertin as a Counsellor of Parliament, all his son's entreaties for release, or for a public trial, were rendered vain, and he lost his commission in the Regiment of St. Jal. Some of his friends, however, having discovered where he was confined, and fearing that he might be secretly put to death, broke into the monastery one night, and assisted him to escape. Through Gascony and Bearn he fled to Spain, where, without so much as a change of clothes, without money or letters of introduction, he arrived, in a famished and destitute condition, at the house of the Comte de Marcillac (a relation of his mother), who derived his title from the little town of that name, nine miles north of Bordeaux.