infusible and insoluble. The chemical name of this
product is "polymerized oxybenzyl methylene glycol anhydride," but
nobody calls it that, not even chemists. It is called "Bakelite" after
its inventor.
The two stages in its preparation are convenient in many ways. For
instance, porous wood may be soaked in the soft resin and then by heat
and pressure it is changed to the bakelite form and the wood comes out
with a hard finish that may be given the brilliant polish of Japanese
lacquer. Paper, cardboard, cloth, wood pulp, sawdust, asbestos and the
like may be impregnated with the resin, producing tough and hard
material suitable for various purposes. Brass work painted with it and
then baked at 300 deg. F. acquires a lacquered surface that is unaffected by
soap. Forced in powder or sheet form into molds under a pressure of 1200
to 2000 pounds to the square inch it takes the most delicate
impressions. Billiard balls of bakelite are claimed to be better than
ivory because, having no grain, they do not swell unequally with heat
and humidity and so lose their sphericity. Pipestems and beads of
bakelite have the clear brilliancy of amber and greater strength.
Fountain pens made of it are transparent so you can see how much ink you
have left. A new and enlarging field for bakelite and allied products is
the making of noiseless gears for automobiles and other machinery, also
of air-plane propellers.
Celluloid is more plastic and elastic than bakelite. It is therefore
more easily worked in sheets and small objects. Celluloid can be made
perfectly transparent and colorless while bakelite is confined to the
range between a clear amber and an opaque brown or black. On the other
hand bakelite has the advantage in being tasteless, odorless, inert,
insoluble and non-inflammable. This last quality and its high electrical
resistance give bakelite its chief field of usefulness. Electricity was
discovered by the Greeks, who found that amber (_electron_) when rubbed
would pick up straws. This means simply that amber, like all such
resinous substances, natural or artificial, is a non-conductor or
di-electric and does not carry off and scatter the electricity collected
on the surface by the friction. Bakelite is used in its liquid form for
impregnating coils to keep the wires from shortcircuiting and in its
solid form for commutators, magnetos, switch blocks, distributors, and
all sorts of electrical apparatus for automobiles, telephones,
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