To Varnish Drawings.

Scientific American 21, 12.2.1848

Boil some clear parchment cuttings in water, in a glazed earthern vessel till they produce a very clear size; strain it and keep it till wanted, then give the work two coats of the size, passing the brush quickly over the work, so as not to disturb the colors.

Or, mix one ounce of Canada balsam and two ounces of spirits of turpentine together, then size the print or drawing with a solution of isinglass in water and when dry apply the varnish with a camel's-hair brush.