The practical carver and gilder's guide and picture frame maker's companion (1900)
Savory, Charles H · London : Kent & Co. ; Cirencester : C. H. Savory · leaf 178
THE CARVER AND GILDER'S GUIDE. 174 Mounts may be cut to any pattern or shape, but the following are recognised shapes for photographs, &c. : — Oval, dome, square, cushion; and drawings sometimes look well with mounts, the top corners of which are rounded. … The above diagrams will illustrate the technical names of mounts : — D, round ; E, square corners ; F, cushion shape ; G, oval ; H, dome-top upright ; A, dome-top landscape ; B, top corners rounded (landscape) ; C, top corners rounded, upright. It is usual with water-colours to have the mounts…
Carving (Decorative arts) · Gilding · Picture frames and framing
Internet Archive · Getty Research Institute · Public domain (published before 1931). Free to use for anything.