Page:The museum, (Jackson, Marget Talbot, 1917).djvu/194

ically that is used in the Albertinum in Dresden which is said to make it possible to wash it later when dirty. European museum directors have spent much more time and study on such problems than our American museum men have done. Experiments are being made in Munich with a shellac mixture. But this discolors the cast in a disagreeable manner. In this country some of our older museums are using white water-color paint on the casts when they become too dirty for exhibition otherwise. Such a proceeding makes every student hold up his hands in horror. The spirit of a work of art is such a delicate and evanescent thing that it is only with the greatest difficulty that it can be caught and imprisoned in a cast. Those who know and appreciate the subtleties of modelling call for a cast made from a mould taken directly from the original and prefer an early cast from that mould rather than a late one, so easily are the shades of surface destroyed. Imagine, then, what a lifeless thing a cast becomes when its surface is covered by layer after layer of calcimine! It is for this reason also that the washing of casts is attended with so much difficulty. The slightest change in the surface of a cast impairs its value, and the problem is consequently to provide a method of filling the pores of the plaster that will make it less