Varnish
As Used in Bookbinding
The first, by the celebrated Tingry, is made in the following manner:—
Put into a vessel six ounces of mastic, in drops, three ounces of sandarac finely powdered, four ounces of coarsely-broken glass, separated from the dust by a sieve, and thirty-two ounces of spirits of wine, of about forty degrees. Place the vessel upon straw in another filled with cold water; put it on the fire and let it boil, stirring the substances together with a stick, to keep the resins from uniting. When the whole appears well mixed, put in three ounces of turpentine, and boil for another half-hour, when the whole must be taken off and stirred till the varnish and the water in which it is placed cools. Next day, filter it through a fine cotton, by which means it will acquire the greatest degree of limpidity, and well cork up in a bottle.
The other recipe is given by Mons. F. Mairet, of Châtillon sur Seine, and may be prepared similar to the above. The ingredients are, three pints of spirits of wine, of thirty-six to forty degrees, eight ounces of sandarac, two ounces of mastic in drops, eight ounces of shell-lac, and two ounces of Venice turpentine.
The varnish is first put on the back of the book with a camel’s-hair brush as lightly as possible. When nearly dry, it is polished with a ball formed of fine white cotton, filled with wool, on which has been rubbed a small quantity of olive-oil, to make it glide freely; it must be rubbed at first lightly, and, as fast as the varnish dries and becomes warm, more sharply. The sides are in like manner polished one after the other.
Varnish is applied after the volume has been polished by the iron, in order to retain the brilliancy and preserve the volume from the bad effects produced by flies eating off the glaire. The manufactured article now in general use is applied by a soft sponge being lightly passed over the volumes after a small portion of varnish has been applied to the sponge.