the brush, or the surface of the paper will be abraised; after which, rinse well with water.
Very often such stains, if fresh, will disappear if a fine jet of water be allowed to play on the parts dirtied, the water being ejected through a fine rose jet.
Fox-marks.—Books so stained may generally be cleaned by immersing the leaves into a weak solution of hydrochloric acid; one must not make the bath too strong, ½ ounce of the acid to 1 pint of water, using the bath hot, will be found about right. Should the marks not give to this treatment, plunge the book, sheet by sheet, into a weak bath of chlorine water. The book may be left in for some hours, taken out and replaced in the hydrochloric bath; after a half hour it may be rinsed with cold water, hung up to dry, and sized.
Finger-marks, commonly called “thumb-marks.”—These are the most difficult to erase, the dirt being generally of a greasy nature, and forced into the fibres of the paper. Make a jelly of white or curd soap, apply to the stain, and leave it on for some time, then wash away gently by means of a soft brush while the leaf is in cold water; this will, as a rule, take all, or nearly all, away. A slight rinsing in very weak acid water, again with cold water, and when dry size.
Blood stains.—The leaves stained must be plunged into cold water; when thoroughly soaked, the stains may be washed with a soft brush charged with soap, then well rinsed with water again. Dry.
If hot water be used, the heat renders the albumen of the blood insoluble, and the stain will be difficult to erase.
Ink stains (writing).—Some inks are more difficult to erase than others. As a rule ink gives way if the writing be treated with a solution of oxalic acid, and afterwards to a weak solution of chloride of lime. It is perhaps better to immerse the whole leaf in the solution, as the lime is likely to bleach and leave a mark; the leaf should in any