How did lantern slides support teaching in the 19th century?

In the 19th century, lantern slides—photographic transparencies projected onto surfaces—served as a foundational technological aid to education. They were primarily utilized in lyceum schools for adults, chautauqua classes, and traveling public-lecture tent shows.12

These visual aids were particularly effective for educating semiliterate audiences, as they allowed instructors to project images onto any convenient surface. By providing a visual component to instruction, lantern slides helped shift educational focus toward visual learning approaches, offering a significant alternative to the oral recitation practices that dominated traditional classrooms at the time.2