Glossary
catalyst
A substance which provokes a chemical reaction in other materials without itself changing. For example, an egg will emulsify water and oil by acting as a catalyst. In resin sculpture, a catalyst must be added in order to cause the resin to harden. An accelerator, usually already added to the resin, reacts with the catalyst and heat is generated which sets off the hardening process.
xylography
A printing technique that involves carving text in relief upon a wooden block. When inked, the impression is transferred to paper. The oldest known printed works were produced by this method in Japan and China during the 8th and 9th centuries. This method of wood-block printing appeared in Europe in the 14th century and eventually inspired Johannes Gutenberg to create type pieces out of metal.
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