He was a zealous supporter of the dispensary for supplying medical and surgical attendance to the sick poor at their own homes, as well as an active and munificent patron of every useful and charitable institution.

When the plan for the medical school, afterwards Queen's College, was matured in 1827, he became president, and during a period of eighteen years was never absent from the meetings of the council.

The eldest son, Johnstone, Edward (1804–1881), claimant of Annandale peerage, born at Ladywood House, near Birmingham, 9 April 1804, was educated at Trinity College, Cambridge, where he graduated B.A.

a question of Geography, History, and Public Law.’ He inherited the estates of Fulford Hall, Warwickshire, and Dunsley manor, Staffordshire.

The second son, Johnstone, James (1806–1869), physician, born at Edgbaston Hall, near Birmingham, on 12 April 1806, matriculated from Trinity College, Cambridge in 1819, graduated M.B.

After studying in Edinburgh, Paris, and London, he settled in Birmingham, where he was appointed the first professor of materia medica and therapeutics at Queen's College in 1841, and extraordinary physician to the General Hospital, a post which he held for more than thirty years.

The best-known of his writings are ‘A Therapeutic Arrangement and Syllabus of Materia Medica,’ 1835, which had an extensive circulation; and ‘A Discourse on the Phenomena of Sensation as connected with the Mental, Physical, and Instructive Faculties of Man,’ 1841.

He married in 1834 Maria Mary Payne, daughter of Joseph Webster of Penns, Warwickshire, and by her, who died in 1859, left twelve children.