This section is from the book "A Treatise On Architecture And Building Construction Vol3: Stair Building, Ornamental Ironwork, Roofing, Sheet-Metal Work, Electric-Light Wiring And Bellwork", by The Colliery Engineer Co.. Also available from Amazon: A Treatise On Architecture And Building Construction.
13. Sheet-metal cornices are made in such a variety of patterns, in such a wide range of sizes, and are required to be placed in such a diversity of situations, that there must be a great variation in the methods of construction. Very many designs, however, correspond as far as having moldings continuous throughout their lengths. All are supported by projecting brackets or lookouts. The joints, shape, and material of the cornice proper, and the construction of lookouts, are the features in cornice work which we will consider in particular.
Cornices are made at the cornice factory according to drawings and specifications, and are shipped in parts to the building.
Brackets, modillions, dentils, etc. are usually secured to the cornice at the factory. Trusses and check or stop blocks are shipped in separate packages. Thus it will be seen that the cornice setter or tinsmith is only required to assemble the several parts and erect them in place on proper supports. The supports in general use are wood or iron, the latter being employed in the better class of buildings.