No force should be applied to separate parts which adhere together; a little warm water and care is sure to overcome that difficulty.

When all the sections are loose, the separate sheets are placed singly in a bath of cold water, and allowed to remain there until all the dirt has soaked out.

If not sufficiently purified, a little hydrochloric or oxalic acid, or caustic potash may be put in the water, according as the stains are from grease or from ink.

Here is where an unpractised binder will probably injure a book for life.

If the chemicals are too strong, or the sheets remain too long in the bath, or are not thoroughly cleansed from the bleach before they are re-sized, the certain seeds of decay are planted in the paper, and although for a time the leaves may look bright to the eye, and even crackle under the hand like the soundest paper, yet in the course of a few years the enemy will appear, the fibre will decay, and the existence of the books will terminate in a state of white tinder.
Everything which diminishes the interest of a book is inimical to its preservation, and in fact is its enemy.