Who invented the pencil?
[ 2006-07-14 10:48 ]
鉛筆是大家從小用到大的東西。不知道你用鉛筆的時候有沒有想過它到底是怎么來的。想了解一下鉛筆是誰發(fā)明的和怎么制作的嗎？趕快看看下面這篇文章吧！
 Pencil, a derivative of the Latin word pencillus for "little
tail," originally described a small, fine, pointed brush.
N. J. Conte, in
1795, successfully produced pencils, after the later famed Faber family of
Nuremberg, Germany, failed to do so, by using a pulverized graphite base to create a substandard,
crude prototype of a pencil. Conte's method, the basic recipe used by all pencil
manufacturers today, differed from the failed Faber fiasco, as he ground
graphite, mixed it with certain
types of clay, pressed the "dough" into sticks, and finished them in a
kiln. The Faber family followed
suit, and achieved the fame and fortune that previously eluded it.
The
recipe used by modern pencil manufacturers, calls for dried, ground graphite, a
form of carbon, mixed with clay and water in varying proportions. Pencils made
with more clay produce a harder pencil, and, conversely, pencils made with more
graphite produce a softer pencil. In either case, the ingredients are mixed
until they reach a doughy
consistency, and then pass through a forming press, which presses the dough into
a pencil thin, smooth, glossy rope. After workers straighten the rope they cut
it into the desired lengths, and bake them in industrial ovens.
While the
mixture is prepared and baked, workers prepare the casing that will house the
lead. They shape the wooden casings, made from either red cedar or pine, into
halves, and carve grooves in them to encase the graphite-based leads. The
workers then carefully insert the finished leads into the grooves, glue the two
wooden halves together, run the resulting slats through a saw that cuts them
into single pencils, and finish them with a shaping machine that smoothes the
pencils' surfaces.
Modern pencils come in over 350 varieties; each
designed for a specific use, and may be purchased in over 72 colors. Black
pencils, or graphite-based pencils, come in 19 degrees of hardness and of
intensity. Specialty pencil leads are crafted to write on surfaces such as
cloth, cellophane, plastics, and movie film. Architects, engineers, and those
doing outdoor construction work primarily purchase these specialty leads, as
they possess non-fade, weatherproof qualities. The versatility of Conte's
brainchild, the pencil, makes it the essential, indispensable tool of these
trades.
pulverize: 研磨成粉
graphite: 石墨
kiln:
窯，干燥爐
doughy: 面團(tuán)似的
（英語點津 Annabel 編輯）
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