[1] Billing was long connected with the London Hospital, to which foundation, after having been engaged in teaching there since 1817, he was elected physician on 2 July 1822.
On the foundation of the university of London in 1836, Billing was invited to become a member of the senate, and occupied an influential position on that body for many years.
[1] After a long and distinguished professional career, Billing retired from practice many years before his death, which occurred on 2 September 1881 at his house in Park Lane.
[1] Billing drew on his experience in a well-known manual, The First Principles of Medicine, which, from its first issue in 1831 that was hardly more than a pamphlet, grew to a bulky text-book.
He gave special attention to diseases of the chest, and was among the earliest medical teachers in London to make auscultation part of regular instruction.
His avowed aim was to base medicine on pathology; a lucid writer, he also stretched a point in favour of logical accuracy.
On this area he published The Science of Gems, Jewels, Coins, and Medals, Ancient and Modern, 1867, which contained a fragmentary autobiography of Benedetto Pistrucci, translated by Billing's wife.