In 1829, Sir James Murray (an Irish physician) used a "condensed solution of fluid magnesia" preparation of his own design to treat the Lord Lieutenant of Ireland of stomach pain; this was so successful that he was appointed resident physician to Anglesey and two subsequent Lords Lieutenant, and knighted.
Sir James Murray (17881871) was an Irish physician, whose research into digestion led to his discovery of the stomach aid Milk of Magnesia in 1809. Murray graduated from the University of Edinburgh as a Doctor of Medicine in 1829, and became the resident physician to Henry Paget, 1st Marquess of Anglesey, in 1831, a post Murray held until the 1840s. In 1809 he developed the foundations of a fluid magnesia, which contained a base ingredient of magnesium sulfate. 
