The varnish.
This is of great importance for the instrument. In the first place it preserves it from the influence of the weather, and then it also has its influence upon the tone. A fine varnish must be transparent, so that the wood underneath may be fully shown up, and it must also be of a fine, but not glaring or staring, colour. The finest varnish is found on the violins of Stradivarius. Two kinds of varnish are used,—spirit varnish,—a gum dissolved in alcohol; and oil varnish,—a gum dissolved in oil of turpentine.