Spirited Conduct of Fritz.--Fortress of Cüstrin.--Prison Fare.-- Wilhelmina’s Captivity.--Sad Fate of Doris Ritter.--Motives of the King.--Doom of Lieutenant Katte.--Pathetic Supplications.-- The Execution.--Peril of Fritz.--Theology of the King.--Letter from Fritz.--Sufferings of Wilhelmina.--Brutality of the King.-- Wilhelmina brought to Terms. The captive Crown Prince was conveyed from Wesel to the castle of Mittenwalde, where he was imprisoned in a room without furniture or bed. An old chest which chanced to be there was his only seat. One of the king’s favorite ministers, Grumkow, with other officials, was sent to interrogate him. The prince, probably aware that nothing which he could now do could make matters worse than they actually were, displayed much spirit in the interview. Frankly avowing his intention to escape, he refused to make any disclosures which should implicate his friends. Grumkow insolently informed him that the use of the rack was not yet abolished in his majesty’s dominions, and that, if he were not more pliant, the energies of that instrument might be called into requisition. Frederick admitted afterward that his blood ran cold at that suggestion. Still he had the nerve to reply, according to the testimony of Wilhelmina, “A hangman such as you naturally takes pleasure in talking of his tools and of his trade, but on me they will produce no effect. I have owned every thing, and almost regret to have done so. I ought not to degrade myself by answering the questions of a scoundrel such as you are.” Grumkow gathered up his papers, and, with his associate officials, departed, probably meditating upon his own prospects should the Crown Prince ever become King of Prussia. The next day, September 5, the captive was taken from the castle of Mittenwalde, and sent to the fortress of Cüstrin, a small and quiet town about seventy miles from Berlin. The strong, dungeon-like room in which he was incarcerated consisted of bare walls, without any furniture, the light being admitted by a single aperture so high that the prince could not look out at it. He was divested of his uniform, of his sword, of every mark of dignity. Coarse brown clothes of plainest cut were furnished him. His flute was taken from him, and he was deprived of all books but the Bible and a few devotional treatises. He was allowed a daily sum, amounting to twelve cents of our money, for his food--eight cents for his dinner and four for his supper. His food was purchased at a cook-shop near by, and cut for him. He was not permitted the use of a knife. The door was opened three times a day for ventilation--morning, noon, and night--but not for more than four minutes each time. A single tallow-candle was allowed him; but that was to be extinguished at seven o’clock in the evening.