Books with color illustrations were once rare and costly, but during the nineteenth century advances in color printing technology allowed publishers to include color more frequently. At the same time teachers and government officials attempted to employ graphic displays to facilitate understanding of often abstract or invisible concepts or to show data in a form that could more easily be grasped and retained. The use of color enhanced these endeavors. Dating from 1847 to 1876, the four books discussed here were selected because their authors deliberately chose to replace the written word with color graphics to provide instruction in the sciences and social sciences.

中文翻译：

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用于视觉教学的 19 世纪彩色印刷

带有彩色插图的书籍曾经很少见且价格昂贵，但在 19 世纪，彩色印刷技术的进步使出版商能够更频繁地包含彩色。与此同时，教师和政府官员试图使用图形显示来促进对通常抽象或不可见的概念的理解，或者以更容易掌握和保留的形式显示数据。颜色的使用增强了这些努力。从 1847 年到 1876 年，这里讨论的四本书被选中，因为它们的作者故意选择用彩色图形代替书面文字，以提供科学和社会科学方面的指导。