In 1849, the
daguerreotypists William and Frederick Langenheim introduced the lantern slide: a transparent image on glass that could be projected, in magnified form, onto a surface using a “magic lantern,” or sciopticon. This new technology expanded the uses of photography, allowing photographic images to be viewed by a large audience. With lantern slides, museum curators and educators could illustrate their lectures, letting audience members see detailed studies of objects and sites from around the world. PhiladelphiaThe ’s lantern slide collection was started by the Museum’s curator of fine arts, William Henry Goodyear, in the late nineteenth century. Brooklyn Museum
See the above page for the full story, together with a link to the fabulous flickr slideshow of some of the lantern slides (hover the cursor over the image and then click on the "i" symbol to see details of each slide's subject matter. Excellent.