The infirmity to which Mr. Pope alludes, appeared to me also, as I have elsewhere observed, to be of the convulsive kind, and of the nature of that distemper called St. Vitus's dance; and in this opinion I am confirmed by the description which Sydenham gives of that disease. “This disorder is a kind of convulsion. It manifests itself by halting or unsteadiness of one of the legs, which the patient draws after him like an ideot. If the hand of the same side be applied to the breast, or any other part of the body, he cannot keep it a moment in the same posture, but it will be drawn into a different one by a convulsion, notwithstanding all his efforts to the contrary.” Sir Joshua Reynolds, however, was of a different opinion, and favoured me with the following paper.
“Those motions or tricks of Dr. Johnson are improperly called convulsions. He could sit motionless, when he was told so to do, as well as any other man. My opinion is, that it proceeded from a habit which he had indulged himself in, of accompanying his thoughts with certain untoward actions, and those actions always appeared to me as if they were meant to reprobate some part of his past conduct. Whenever he was not engaged in conversation, such thoughts were sure to rush into his mind; and, for this reason, any company, any employment whatever, he preferred to being alone. The great business of his life (he said) was to escape from himself; this disposition he considered as the disease of his mind, which nothing cured but company. “One instance of his absence of mind and particularity, as it is characteristick of the man, may be worth relating. When he and I took a journey together into the West, we visited the late Mr. Banks, of Dorsetshire; the conversation, turning upon pictures, which Johnson could not well see, he retired to a corner of the room, stretching out his right leg as far as he could reach before him, then bringing up his left leg, and stretching his right still further on. The old gentleman observing him, went up to him, and in a very courteous manner assured him, though it was not a new house, the flooring was perfectly safe. The Doctor started from his reverie like a person waked out of his sleep, but spoke not a word.”
 While we are on this subject, my readers may not be displeased with another anecdote, communicated to me by the same friend, from the relation of Mr. Hogarth.
 Johnson used to be a pretty frequent visitor at the house of Mr. Richardson, authour of Clarissa, and other novels of extensive reputation. Mr. Hogarth came one day to see Richardson, soon after the execution of Dr. Cameron, for having taken arms for the house of Stuart in 1745-6; and being a warm partisan of George the Second, he observed to Richardson, that certainly there must have been some very unfavourable circumstances lately discovered in this particular case, which had induced the King to approve of an execution for rebellion so long after the time when it was committed, as this had the appearance of putting a man to death in cold blood, and was very unlike his Majesty's usual clemency. While he was talking, he perceived a person standing at a window in the room, shaking his head, and rolling himself about in a strange ridiculous manner. He concluded that he was an ideot, whom his relations had put under the care of Mr. Richardson, as a very good man. To his great surprize, however, this figure stalked forwards to where he and Mr. Richardson were sitting, and all at once took up the argument, and burst out into an invective against George the Second, as one, who, upon all occasions, was unrelenting and barbarous; mentioning many instances, particularly, that when an officer of high rank had been acquitted by a Court Martial, George the Second had with his own hand struck his name off the list. In short, he displayed such a power of eloquence, that Hogarth looked at him with astonishment, and actually imagined that this ideot had been at the moment inspired. Neither Hogarth nor Johnson were made known to each other at this interview.