, are mixed in.
Without going into the question of their variations and relative merits
we may consider the advantages of the pyroxylin plastics in general.
Here we have a new substance, the product of the creative genius of man,
and therefore adaptable to his needs. It is hard but light, tough but
elastic, easily made and tolerably cheap. Heated to the boiling point of
water it becomes soft and flexible. It can be turned, carved, ground,
polished, bent, pressed, stamped, molded or blown. To make a block of
any desired size simply pile up the sheets and put them in a hot press.
To get sheets of any desired thickness, simply shave them off the block.
To make a tube of any desired size, shape or thickness squirt out the
mixture through a ring-shaped hole or roll the sheets around a hot bar.
Cut the tube into sections and you have rings to be shaped and stamped
into box bodies or napkin rings. Print words or pictures on a celluloid
sheet, put a thin transparent sheet over it and weld them together, then
you have something like the horn book of our ancestors, but better.
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