As the summer of 1786 gradually returned he began to improve, so he went from Potsdam to Sans Souci, which he never left alive. He was then under the care of the Court physicians, Selle and Cothenius, and the surgeon Frese. Unfortunately for Dr. Selle he hinted that the great man probably had dropsy, so Frederick flew into a rage, dismissed him, and wrote to Hanover, where there dwelt an eminent man of the name of Dr. Zimmermann, who arrived at Potsdam on June 26th, 1786. When Frederick saw him he asked at once, “Doctor, can you cure me?” To which Zimmermann, being evidently a courtly fellow, answered, “I can relieve you, sir.” Zimmermann, it strikes one, must have known that men like Selle and Cothenius would know enough about their patient to render it dangerous for any outsider to offer an opinion carelessly. The first thing for Zimmermann to do was evidently to try to gain his patient’s confidence, because never was there a more unruly man, especially where eating and drinking were concerned. The doctor found that Frederick would talk on literature and poetry as long as he would allow him, although it made him cough violently; and his first line of treatment was to get Frederick to promise to read through _The Decline and Fall of the Roman Empire_. No doubt he thought that that gigantic book would be a good way of keeping his patient quiet for a very long time. Then the conversation would shift to other sovereigns; and Zimmermann was able to give Frederick some of the truth about the health of Empress Catherine of Russia, whose surprising immorality must have been an attractive feature to a soldier. “But,” said Zimmermann, “she boasts that her health costs her only eighteenpence a year!” “Wonderful!” applauded the aged emperor, “I always said she was a woman of supreme genius.” Then Zimmermann, seeing that Frederick was really ill, asked that he might be allowed to have a consultation with the dismissed Selle. This threw Frederick into a passion; his face flushed beneath the paint, and his eyes glowed with a deepened fury; his voice roared with anger; one fit of violent coughing after another came upon him, so that Zimmermann thought it wiser to desist, and return to his talk of scandal or literature. But he had already gained sufficient information to leave us a valuable report as to the king’s physical condition. “His legs were swollen with dropsy, which also extended up on to the skin of the abdomen, and, though he was not feverish, his pulse was hard and violent.” That is to say, he was probably suffering from a high blood-pressure with failing heart, which was causing his dropsy.