The temperature at which the work is to be fired, must, of course, depend upon the qualities of the clay of which the piece of ware is made. As has been said before, this clay should be one that does not require an excessive degree of heat in firing. The exact degree can be estimated by the potter who understands the requirements of the clay which has been used in the manufacture of the particular piece of ware in question. It may be said that the temperature at which Rockingham ware is fired is suitable for this work, and that a glaze such as that used upon that kind of ware can be used with good results. It is possible to have a glaze so adapted to the body of the ware as to prevent it from crazing, and yet preserve the brilliancy of the colors. CHAPTER V. MODELING IN RELIEF. Under this head may be comprised the decorative modeling of figures and other designs upon pottery, in various degrees of relief. First, we have figures in relief forming decorations upon vases. These, as well as other designs in high relief, belong properly to the domain of sculpture, and the methods of producing them do not vary essentially from those in use in that art. The final process in this case is the firing, instead of the casting in plaster and cutting in marble. Of the methods of producing floral designs in relief, a few suggestions may be of use. These, as well as the painting described in the previous chapter, must be executed when the body of clay, to which they are applied, is very wet, and the applied clay must in this case be, as nearly as possible, in the same condition. If the clay is not in the proper condition, the work will crack in drying.