Panel painting uses heated wax as the medium for the pigments. This was replaced before the end of first millennium by tempera, which uses an egg-yolk medium. Using small brushes dipped in a mixture of pigment and egg-yolk, the paint was applied in very small, almost transparent, brushstrokes. Thin layers of paint would be used to create volumetric forms. By the beginning of the 15th century, oil painting was developed. This was more tolerant, and allowed the exceptional detail of Early Netherlandish art. This used a very painstaking multi-layered technique, where the painting, or a particular part of it, had to be
What Bird is That? Edition What Bird is That?" was published by Australia's Heritage Publishing in 2011, the latest release of Cayley’s “big bird book” complete with Lindsey’s revisions. It is 832 pages, features 769 birds and includes all 460 of Cayley’s full-colour paintings, many showing groups of related birds. New to this edition was an accompanying e-book "What Bird Call is That?", which identifies and illustrates 101 birds from "What Bird is That?", as well as providing sound files of each featured bird’s distinctive call. The sound files were provided by David Stewart. "What Bird is That?" plays a central role in Australian