see a clear and sharp impression of his types on
the paper should not neglect to look sometimes to the thermometer, too low
or too high a temperature being much oftener the cause of unsatisfactory
printing than the ink we use.

WHEN TO WASH ROLLERS.

The press or machine man must be guided by the condition of the face of
the roller, and the eyes and fingers will be the best guides. Where
machine rollers are required for a weekly newspaper, they should be washed
ready for the first set of forms, and when the number is long, a second
set should be got ready and inked to work the second side, as the paper
throws off a quantity of cotton waste, and powder, and neutralizes the
tack so necessary to the face of a good roller and a clear impression.
Should a roller require cleaning for a hurried work, the old ink may be
removed with turpentine, but must be done quickly, and immediately
distributed on the ink table, or the face will harden.

IMPROVED DRYER FOR PRINTING INK.

A small quantity of perfectly dry acetate of lead or borate of manganese
in impalpable powder will hasten the drying of the ink. It is essential
that it be thoroughly incorporated with the ink by trituration in a
mortar.

HOW TO BEND A RULE.

To bend a rule, get it thoroughly hot and let it cool slowly; this will
take the spring out, and it will stay in the shape it is bent to.

TO CLEAN GILT FRAMES.

Use a soft sponge moderately moistened with spirits of wine; allow to dry
by evaporation. Do not use a cloth, and avoid friction. Another way is to
use a very soft shaving brush, and to gently rub backward and forward a
lather of curd soap. Rinse with water at about blood heat. This applied
morning after morning to old and dirt-covered oil paintings will greatly
restore them. In adopting this plan with regard to gilt frames around
water colors or prints, be sure that not enough moisture is used to run
off the frame, or the paper will be stained. The cleaning applies to gold
frames only. Dutch metal will bear no cleaning, but a new material, not
absolutely gold, but very like it, will stand any amount of soap and
water.

CLEANING NEW MACHINERY.

As presses and machinery have their bright work covered with a compound to
keep it from rusting while shipping, parties who receive the machinery
will find benzine or kerosene oil the best articles to clean off the
compound with.

TO MAKE INVISIBLE WRITING.

To make secret or invisible writin