Evolution and types of pencils
the vast majority of people on our planet use the pencil on a level with the handles since childhood. But if the handle is more of a writing tool, the pencil is indispensable while drawing, both artistic and technical (drawing). Acquaintance with him begins long before school, and the cooperation continues almost all their life, regardless of profession.
History
Most modern pencils are made up of two components:
the-
the
- graphite rod; the
- wooden Dolly.
This arrangement allows you to maintain the integrity of the long and thin stylus. It looks a fairly simple design, which meanwhile, requires a complex preparation of production, for which there is a few hundred years of evolution.
First prototypes of the pencils appeared in the 13th century, but they used a slate or silver cores. Graphite rods were first adopted at the turn of 16-17 centuries, though to call them long and thin, the language is not rotated. In fact it was oblong pieces of rock that were clamped between pieces of wood or wrapped in paper.
the Peak of the design of the pencil falls on the 18th and 19th century, when was invented the shape and composition of the rods (round and faceted).
Stylus and hardness
Most modern pencils have yourself a marking which indicates the hardness of the stylus. This parameter depends on the ratio of components in the composition of the material of the rod. First experiments in this direction conducted by the founder of pencil Empire "Kohinoor" Joseph Hardmuth in the late 18th century. Almost a century later, his grandson corrected composition, thereby creating, in practice, the pencils of 17 levels of hardness.
In droves implemented 5 types of pencils in hardness of the rod:
-
the
- M/ - a soft pencil. Has a more dark, close to black color; the
- NV/TM - hard-soft stylus, which is the most universal and widespread of all produced; the
- N/T - solid pencils.
in addition to classic wooden or plastic models, today there are also mechanical pencils, the main advantage of which is the possibility of replacing the rods, without the need of honing.
If you need such it will not be easy. All you need is to type in browser address of the site and then just search the online catalog to select item.
Translated by "Yandex.Translate": translate.yandex.ru.
