OCR Text |
Show ART PRESERVATIVE AIDED. Influence or Mcii'nlviilnc unit i:icclro-yi'tff i:icclro-yi'tff on Modern r rlmliie. Thu development of book nnd newspaper news-paper printing has been aided to nn extraordinary degree by stereotyping, says the Scientific American. The stereotyping plntes or tho matrices can bo stored for future uso at low expense ex-pense nnd tho typo can be distributed and used nnew. It was made practical practi-cal by Karl Stanhope about 1S01, nnd was Introduced lu New York about 1813. The plaster nnd clap processes were superseded in 1820 by tho nanler- macho process, in which a mold is tak. en on prepared paper, which Is baked, and which can then be curved, if necessary. nec-essary. Periodicals, other than dallies, and books nre usually printed from electrotypes, which process was tried experimentally in Now York in 1841 by Professor Mopes. An Impression Is taken in specially prepared wax, and the mold Is blacklcaded to Insure electrical contact. It is then placed In a plating bath nnd n shell of copper Is deposited. This Is stripped from the mold, curved if necessary, tho back Is tinned, and nn alloy resembling typo metal in then poured over It, to give it strength. The electrotype Is then planed so that it will bo typo high when blocked. Original half-tone cuts nre often soldered or oast In to Insure In-sure good printing results. |