62
Preservative of Rollers when not in Use 62
Rollers in Summer Time 63
To Keep Green Mould from Rollers 63
Treatment of Old Rollers 64
A Recipe for Printer's Rollers 64
When to Wash Rollers 66
Oils for Lubricating Roller Moulds 62

PRINTING METHODS.

Gloss Printing 49
Colors for Printing 51
Off-Setting 83
Printing Envelopes 60
On "Casting Up" 74
To Prevent Set-off 61
Temperature of the Pressroom 65

LYE.

A Strong Lye 79
A Cheap Lye 77

Paper and Printing Recipes.

HOW TO REMOVE COMMON WRITING INK FROM PAPER WITHOUT INJURY TO THE PRINT.

Common writing ink may be removed from paper without injury to the print
by oxalic acid and lime, carefully washing it in water before restoring it
to the volume.

TO RENDER PENCIL NOTES INDELIBLE.

Pencil notes found in a book, or placed there as annotations, may be
rendered indelible by washing them with a soft sponge dipped in warm
vellum size or milk.

TO REMOVE GREASE SPOTS FROM PAPER.

Grease may be removed from paper in the following manner: Warm gradually
the parts containing the grease, and extract as much as possible of it by
applying blotting-paper. Apply to the warm paper with a soft, clean brush,
some clear essential oil of turpentine that has been boiled, and then
complete the operation by rubbing over a little rectified spirits of
wine.

HOW TO DETECT ARSENIC IN PAPER.

A simple method for detecting arsenic in paper, cards, etc., is described
as follows:--Immerse the suspected paper in strong ammonia on a white
plate or saucer; if the ammonia becomes blue, the presence of salt of
copper is proved; then drop a crystal of nitrate of silver into the blue
liquid, and, if any arsenic be present, the crystal will become coated
with yellow arseniate of silver, which will disappear on stirring.