It was after their return to London that Boswell won the greatest triumph of his friendship.  He carried through a negotiation, to which, as Burke pleasantly said, there was nothing equal in the whole history of the corps diplomatique.  At some moment of enthusiasm it had occurred to him to bring Johnson into company with Wilkes.  The infidel demagogue was probably in the mind of the Tory High Churchman, when he threw out that pleasant little apophthegm about patriotism.  To bring together two such opposites without provoking a collision would be the crowning triumph of Boswell’s curiosity.  He was ready to run all hazards as a chemist might try some new experiment at the risk of a destructive explosion; but being resolved, he took every precaution with admirable foresight.

Boswell had been invited by the Dillys, well-known booksellers of the day, to meet Wilkes.  “Let us have Johnson,” suggested the gallant Boswell.  “Not for the world!” exclaimed Dilly.  But, on Boswell’s undertaking the negotiation, he consented to the experiment.  Boswell went off to Johnson and politely invited him in Dilly’s name.  “I will wait upon him,” said Johnson.  “Provided, sir, I suppose,” said the diplomatic Boswell, “that the company which he is to have is agreeable to you.”  “What do you mean, sir?” exclaimed Johnson.  “What do you take me for?  Do you think I am so ignorant of the world as to prescribe to a gentleman what company he is to have at his table?” Boswell worked the point a little farther, till, by judicious manipulation, he had got Johnson to commit himself to meeting anybody—­even Jack Wilkes, to make a wild hypothesis—­at the Dillys’ table.  Boswell retired, hoping to think that he had fixed the discussion in Johnson’s mind.

The great day arrived, and Boswell, like a consummate general who leaves nothing to chance, went himself to fetch Johnson to the dinner.  The great man had forgotten the engagement, and was “buffeting his books” in a dirty shirt and amidst clouds of dust.  When reminded of his promise, he said that he had ordered dinner at home with Mrs. Williams.  Entreaties of the warmest kind from Boswell softened the peevish old lady, to whose pleasure Johnson had referred him.  Boswell flew back, announced Mrs. Williams’s consent, and Johnson roared, “Frank, a clean shirt!” and was soon in a hackney-coach.  Boswell rejoiced like a “fortune-hunter who has got an heiress into a post-chaise with him to set out for Gretna Green.”  Yet the joy was with trembling.  Arrived at Dillys’, Johnson found himself amongst strangers, and Boswell watched anxiously from a corner.  “Who is that gentleman?” whispered Johnson to Dilly.  “Mr. Arthur Lee.”  Johnson whistled “too-too-too” doubtfully, for Lee was a patriot and an American.  “And who is the gentleman in lace?” “Mr. Wilkes, sir.”  Johnson subsided into a window-seat and fixed his eye on a book.  He was fairly in the toils.  His reproof of Boswell was recent enough to prevent him from exhibiting his displeasure, and he resolved to restrain himself.