| 摘要 |
The globe is composed of a synthetic resin and stone powder mixed in the ratio of 10:1 and is injection molded in metal molds in two semispherical parts to be assembled into a globe. the semispherical concave surface of the mold has a patterm formed intaglio by etching to depict the coast lines, latitude and longitude of the world map on the formed glabe. The surface is also treated to a 800 mesh roughness by sand blasting to form on the globe a roughened surface to function as a blackboard for erasably marking or writing notes on it with chalks for convenience. The hardness of the glabe prolongs its durability for a long time.
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