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Various

"Scientific American Supplement, No. 358, November 11, 1882"


The stone is broken up with a hammer into pieces, which are then ground
round in a mill. The mill has a fixed slab of stone, with its surface
full of little grooves or furrows. Above this a flat block of oak wood
of the same size as the stone is made to turn round rapidly, and, while
turning, little streams of water run in the grooves and keep the mill
from getting too hot. About 100 pieces of the square pieces of stone
are put in the grooves at once, and in a few minutes are made round and
polished by the wooden block.
China and white marbles are also used to make the round rollers which
have delighted the hearts of the boys of all nations for hundred of
years. Marbles thus made are known to the boys as "chinas," or "alleys."
Real china ones are made of porcelain clay, and baked like chinaware or
other pottery. Some of them have a pearly glaze, and some are painted in
various colors, which will not rub off, because they are baked in, just
as the pictures are on the plates and other tableware.
Glass marbles are known as "agates." They are made of both clear and
colored glass. The former are made by taking up a little melted glass on
the end of an iron rod and making it round by dropping it into a round
mould, which shapes it, or by whirling it around the head until the
glass is made into a little ball.


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