‘They are shut up within walls at 9 at night. This discipline hath indeed taken some pains and resolution, as well as some expense, to establish it.’ Along with this work in King’s College, John Gregory engaged in general practice as a physician. He found it very engrossing, much more so than the philosophical teaching which he had to give, and he determined to resign his regentship, and to go abroad for a few months. On his return he fell in love with the Hon. Elizabeth Forbes, a daughter of William, Lord Forbes. She was a beautiful girl, very clever, and she was besides an heiress, and there is a story that her father did not at all approve of the marriage. ‘What do you propose to keep her on?’ said he, and Gregory, getting angry, took his lancet out of his pocket, and said, ‘on this.’ They were married in 1752. Their life was a singularly happy one, to use the expression of their own day, ‘they mutually enjoyed a high degree of felicity.’ For two years they were in Aberdeen, and then Gregory got impatient of his small practice, for there was only room there for one Dr Gregory, and he made up his mind to seek his fortune in London. This was a step which he was glad of all his days, for it brought him into contact with so many interesting people. ‘In London,’ says Lord Woodhouselee, he was ‘already known by reputation as a man of genius.’ How this could be, seeing that he had done little to show his talents, it is difficult to understand. Perhaps some one who knew him in the old Leyden days had spread a report of his brilliancy, or some Aberdonian may have named him as a coming power. However it happened, the effect was most fortunate, for not only was he recognised by the scientific world, and made a Fellow of the Royal Society, but Sir George Lyttelton and Mrs Montague, ‘that fascinating humbug,’ made friends with him, and whatever Mrs Montague was to other people, she was most sincerely kind to the Gregories.