Color-blindness in railway employees
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Article
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1879
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Elsevier Science
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English
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Co!or-Bli~dness in ]~aihvay .Em21oyees. 253 at much less cost than photographs. To produce the best results special negatives arc required to produce the printing plate, and care and skill is required of' the printer. The Artotype specimens exhibited before you to-night will, I think, convey some id