be taken not to rub the surface with a cloth as it easily takes on a decided polish. If this polish comes, it can be dimmed with clear turpentine. A cast that has been so treated can be washed with cold water and a sponge and, in case the dirt persists, with turpentine on clean cotton waste. After it has been washed, however, it is very desirable that it should be treated again with the turpentine and wax. There is often a certain difference in the quality of the surface of the plaster which does not show if the cast is left untreated but which with the application of any solution causes spots of a grayish color to appear. There is no help for this, although when thoroughly dry the difference is not very marked. The third process is the application of zapon, with which the author has had no experience.
Patinating.—The coloring of casts to imitate the material of the original is a process which has been called patinating. It is in use in the Kaiser Friedrich Museum in Berlin, in the Trocadero in Paris and in many other of the fine European cast collections. In this country it has so far been little used and museum officials are still arguing as to the ethics of the procedure. There is no doubt whatever that the impression made upon the public is much more pleasing and also much more true if the casts look something like
