Considered, in the late 18th and early 19th Century, to be the highest form of painting. English historical art used elevated subject matter, and was influenced by Reynolds's Discourses and the work of Benjamin West (1728-1820) at the Royal Academy. The Grand Manner emphasised the heroic and the sublime. Within academic theory it promoted the generalisation of subjects from classical history and mythology, although Biblical scenes were admitted. Tended towards the use of dark colours in imitation of the old masters and the use of bitumen with consequent technical deterioration of works. Unsatisfactory technical procedures in fresco painting, particularly for the London climate, also led to poor preservation of works. Artists include: James Barry, Benjamin Robert Haydon, William Hilton (1786-1839), George Hayter (1792-1871), Daniel Maclise (1806-1870), and William Dyce.