At the height of his popularity St. John Long was making an income of over £13,000 a year (_Gent. Mag._ 1843). That was in 1829. The next year, 1830, he was tried for manslaughter, a young Irish lady, Miss Catherine Cushin, having died after, and it was alleged in consequence of, his treatment. A number of aristocratic patients gave evidence in his favour, and Mr. Justice Park, who tried him, summed up strongly on his behalf. But the jury found him guilty, and he was sentenced to pay a fine of £250 or to be imprisoned until the money was paid. Long ostentatiously produced a roll of notes, counted out the amount, and then drove off from the court in the Marquis of Sligo’s carriage. Next year a coroner’s jury returned another verdict of manslaughter against him in connection with the death of a Mrs. Lloyd. He was again tried but on this occasion was acquitted. Strong articles against him appeared in many of the principal newspapers, but his aristocratic clients as a rule remained faithful to him. He published a book in defence of his system and included in it a number of extraordinary testimonials, together with a series of smart attacks on the medical profession. He retained his popularity to the last; but it was not to be for long. He was attacked by the disease over which he had claimed to exercise so much power, and he died from consumption in 1837 in the 37th year of his age. A graceful monument was erected in Kensal Green Cemetery to his memory by his patients and admirers “to show how much its inhabitant was respected by those who knew his worth, and the benefits derived from his remedial discovery.” His estate became the subject of a lengthy litigation, the principal claimant being an elderly woman of evidently humble surroundings, who, it was proved, was his lawful wife. He had married her when a lad, but had afterwards induced her to agree to an amicable separation. It was then remembered how steadfastly the charlatan had resisted the blandishments of his society friends, many of whom in very high circles had shown their infatuation with the attractive Irishman.