Besides this great undertaking, he corrected his tragedies. As usual, he infected all round with his love of the drama. A theatre was established at court; the brothers and sisters of the king took parts in his plays, and submitted to his instructions. This was a species of flattery well suited to turn a poet's head; yet soon, very soon, the dark cloud appeared in the horizon, and his attention became roused to assure himself whether indeed he heard the far off thunder of an approaching storm. These dawnings of fear and distrust are ingenuously detailed in his letters to his niece. [Sidenote: Nov. 6. 1750.] "It is known, then, at Paris," he writes, "that we have acted the death of Cæsar at Potzdam; that prince Henri is a good actor, has no accent, and is very amiable; and that pleasures may be found here. All this is true--but--the suppers of the king are delicious--seasoned by reason, wit, and science--liberty reigns over them--he is the soul of all--no ill-humour, no clouds--at least, no storms; my life is independent and occupied; but--but--operas, plays, carousals, suppers at Sans-souci--warlike manœuvres, concerts, study, readings; but--but--the weather, my dear child, begins to be very cold----" Such were the first expressions of distrust inspired by observing a certain degree of deceit in the king. He found that he could turn those into ridicule whom he flattered most to their face; and he also found that such blowing of hot and cold with the same breath, which is deemed almost fair in some societies, was fertile of annoyance when practised by a king whose word is law, whose smiles are the ruling influence of the day, whose slightest remark is reported, magnified, and becomes the rule of action to all around; and he began to feel that the chain that bound him and the king, which he flattered would be worn equally by both, fell heavily round him only. He became aware that the king was not the less despotic and self-willed for being a philosopher. In truth, Frederic and Voltaire had a mutual and sincere love for each other. They agreed in their opinions, they sympathised in their views. Each enjoyed the conversation, the wit, the gaiety, the genius of the other; but Voltaire panted for entire independence: to think, to speak, to write freely, was as necessary as the air he breathed. To gain these privileges he had quitted France; and though he passionately loved flattery and distinction, yet these were only pleasing when they waited upon his every caprice; and became valueless when he was called upon to sacrifice the humour of the moment to gain them. The king delighted in Voltaire's talents; but, then, he wished them to be as much at his command as a soldier's valour, which deserves reward, but which may only be displayed at the word of command.