This process may
prove useful for the preservation of plans or designs when the want of
time or any other cause will not allow the draughtsman reproducing them in
ink. A simpler method than the above, however, is to brush over the back
of the paper containing the charcoal or pencil sketch with a weak solution
of white shellac in alcohol.

CARE OF WOOD TYPE.

Wood type should always be kept in a cool and dry place--not, as is often
the case, a few feet from a large stove, or directly over the lye and wash
tub. The drawer or shelves--drawers or cases are preferable to
shelves--where they are kept, should not, as very often happens, be made
of unseasoned wood, for this reason: type wood is usually perfectly
seasoned, and when allowed to remain for any length of time on a damp
surface, the moisture is absorbed, the bottom expands, and a warped type,
ready to be broken at the first impression, is the result.

Wood type should only be washed with oil. A moistened cloth is sufficient,
is more economical, and is certainly much cleaner than using their weight
in oil. All wood type have a smooth and polished face, and if properly
cleaned when put away will last for years. In fact, proper use only
improves the working qualities. Wood type forms should not be left
standing near hot stoves, or left locked up over night on a damp press or
stone to warp, swell, and perhaps ruin a costly chase.

COPPER-PLATING ON ZINC.

Take an organic salt of copper--for instance, a tartrate. Dissolve 126
grammes sulphate of copper (blue vitriol) in two litres of water; also
227 grammes tartrate of potash and 286 grammes crystallized carbonate of
soda in 2 litres of water. On mixing the two solutions, a light
bluish-green precipitate of tartrate of copper is formed. It is thrown on
a linen filter and afterwards dissolved in half a litre of caustic soda
solution of 16 deg. B. when it is ready for use.

The coating obtained from this solution is very pliable, smooth and
coherent, with a fine surface; acquires any desired thickness if left long
enough in the bath.

Other metals can also be employed for plating, in the form of tartrates.
Instead of tartrates, phosphates, oxalates, citrates, acetates and borates
of metals can be used; so that it seems possible to entirely dispense with
the use of cyanide baths.

TO TRANSFER ENGRAVINGS TO MOTHER-OF-PEARL.

To transfer engravings to mother-of-pearl, coat the shell with thin white
copal varn