Lantern Slide Lecture Series


Portrait of William Wagner, ca. 1865.

To William Wagner, a well-rounded citizenry was of the greatest benefit to a modern, industrializing society. This being so, his lecture courses were designed as they would be in a university.  Finding a way to blend vernacular science with more rigorous scientific investigation was a difficult task, but Wagner was up to the challenge. Using objects to illustrate lectures offered a way for both men of science and the general public to learn from sensory investigation. Wagner’s dedication to object-based learning in the early years foreshadowed his later passion for new media technology as a viable method for scientific instruction. As part of a new public sphere, the lecture hall became a space where the public and the professional participated in scientific discourse aimed at celebrating man’s domination of matter, time, and space.[1]

Though the Institute was far from the densely populated city center, it was appropriately situated in a “neighborhood where improvements were progressing most rapidly, and is surrounded by a population to whom its lectures will be of the greatest value.”[2] The warm, sunny afternoon drew a diverse crowd as men of science, Philadelphia’s elite, and casual onlookers bore witness as Wagner dedicated his institute to “the pursuits and advancements of science to the citizens of Philadelphia, forever to be called the Wagner Free Institute of Science.”[3] By the time of the inaugural lectures in 1867, the auditorium was capable of seating 1,300, the arsenal of scientific apparatus for demonstration had increased substantially, and the enthusiasm for the lectures was growing at a rapid pace. In this new space, Wagner and his dedicated staff embraced the advancement of new media technology as a way to engage the public in scientific discourse.

The lantern slide projector at The Wagner Free Institute of Science.

One machine in particular that would help them with this goal was the magic lantern. The magic lantern was the first medium to contest the printed word as a primary mode of information and instruction.[4] Invented by Dutch physicist Christiaan Huygens in the seventeenth-century, the lantern became a popular device for both entertainment and scientific purposes. Primarily used in the seventeenth century to display the marvels of the new sciences, from its inception, the lantern has been tied to science and the Enlightenment. However, the popularization of the device in the eighteenth century was more for its entertainment value. The spectacle of illusion was a popular theme for early lantern users. In the last decade of the century, however, there was a shift in the use of the lantern from the trickery of the phantasmagoria, to a more universal use of the lantern as a teaching device. Scientists adopted it as a way to illustrate recent discoveries in optics and the manipulation of light. This was a time of great optical discovery as scientists were pushing the boundaries of visual observation.

Before the invention of photography, lecturers would illustrate hand drawn images with the lantern. This was usually a supplement to other visual materials, such as dioramas and panoramic paintings. However, with the introduction of the daguerreotype process in 1839, it was not long before the two technologies intersected to create a new way of observing the natural world. In fact, by mid-century, the manufacture of lanterns and of the slides themselves had been industrialized, including the adoption of photography to mass reproduction via photographs printed on glass plates.[5] The marriage of photography and the magic lantern gave rise to a truly mass audience, and institutions adopted the lantern show for its entertainment and instructional value.[6] Philadelphia became a major center of photograph and lantern slide production during this period, and would remain that way for several decades.[7] It was here that the brothers Wilhelm and Frederick Langenheim revolutionized the photographic image. Having been influenced by William Henry Fox Talbot’s albumen printing process, the Langenheims improved upon this by applying the emulsion to glass plates.[8] This was a revolutionary development in the evolution of the media. Now able to capture images directly to glass, the brothers were successful at creating the first photographic lantern slides. In fact, the first public show using photographic lantern slides took place in their Philadelphia studio in 1849.[9] Now that lantern slides could show actual photographic images, facsimiles of the real world, the lantern became a standard device for the public exhibition of scientific discovery.

Advertisement for an 1895 Lecture at the Wagner Free Institute of Science.

Of the many scientific apparati introduced in the nineteenth century, none was more capable at exhibiting phenomena than the magic lantern. Wagner, always a proponent of using objects to teach science, viewed this new technology as a way to better engage his students. The lantern allowed the professors at the Wagner “to convey to the minds of their hearers through the eye as well as the ear.”[10] This led William Wagner to procure the Institute’s first stereopticon, a magic lantern modified for photographic images.[11] Though there is not much reference in the Annals to the lantern’s use until 1871, it can be surmised that the professors at the Wagner were steadily incorporating the device into the curriculum. Advertisement literature from this period often mentioned the stereopticon or stated that lectures were, “Illustrated by Lantern Slide Views.”[12] The 1870s at the Wagner was a time of great experimentation with this new media. Wagner built his arsenal of lantern slides and scientific apparatus at a rapid pace. In October 1875 he wrote in the Annals, “We have acquired…the finest London made Stereopticon…with 250 slides of rare objects of nature, with a microscopic attachment, and numerous prepared objects, also a Camera Obscura, and physical instruments embracing Galvanic magnetism, Electric, Chemical, Hydrostatics, Pneumatics, Gravitation, Optics.”[13]

Wagner’s enthusiasm for experimentation with the latest technological inventions is testament to his dedication to object-based teaching. Observing the audience, Wagner was able to deduce that using new technology would enable his listeners to better comprehend the difficult course material. To Wagner this was the way of bridging the gap between the professional and the vernacular sciences. Engaging the public with hands-on experiments and visual elements created a multisensory experience that made sense to his students. This also meant that course material would not have to be tailored for public consumption, a common critique of nineteenth-century public science.[14] After one particular lecture on botany, in March of 1878, in which the lecturer used photographs from a recent trip to France, Wagner reflected on the power of this approach. “The spring season of the year…brought large audiences…the very extensive series of beautiful French photographs…were projected on the screen by means of the Stereopticon. This mode of object teaching, which holds the attention of the audience through the entire lecture, beyond a doubt is the true principal and plan of teaching science.”[15] As the decade wore on, it became imperative that the professors illustrate their lectures with “lantern slide views.”

Lantern Slide Cabinet in the Lecture Hall of the Wagner Free Institute of Science.

Toward the end of the lecture season of 1878, after several years of testing his method, Wagner was confident that the new visual technology was going to fundamentally change the way in which the sciences were taught. After a series of lectures given by Dr. M.G. MacClanell, “a man of profound learning in Anatomy and Physiology,” Wagner became incensed over MacClanell’s failure to use the stereopticon to illustrate his lecture. He remarked that, “his class failed to comprehend meaning from the rapidity of his diction. This course would have been deeply interesting and instructive had he pursued the same course other professors have done by projecting the many photos I had prepared for his illustration on the screen, but which he would not do.”[16] MacClanell’s inability to adapt to new technology and Wagner’s insistence upon visual instruction, led to MacClanell’s departure at the end of his lecture series. This was a pivotal moment in the early history of lectures at the Wagner. Wagner decided that from then on the Institute would be dedicated to scientific instruction through object-based learning. To him, object teaching had become so popular, that it was, “now indispensable in scientific instruction, and with us so successful that we intend to adopt it all together.”[17] His decision was not unfounded. In an 1879 statement published in the Philadelphia Evening Bulletin, Wagner’s students thanked him for the “rare opportunity of instruction without money and without price.” Furthermore, they remarked on Wagner’s use of technology in his lectures and how it remedies the “difficult problems of science by reaching the minds as well by the eye as the ear.”[18]

The 1870s were a decade of substantial growth for the Wagner Free Institute of Science. By the end of the decade Wagner had devised a new methodology for his courses and supplied the Institution with all of the newest scientific technologies, which made them a popular attraction for both the serious scholar and members of the general public. In 1882 he remarked, “Having long since been impressed with the importance of illustrating our lectures by means of the Lantern Screen, that the different subjects we treat in our lectures may be fully understood, I have devoted much time and expense in adding to our collection many hundred photographic slides in all the department of science in which we teach.” His unabashed embrace of new media would continue until his death in 1885. Always in touch with current trends in technology, Wagner built upon his collection of photographs and slides until the collection was “so large as to cover the whole field of science.”[19]

An 1892 Ticket to an Exhibition of Lantern Slides at the Wagner Free Institute of Science.

The 1890s also saw a marked increase in the use of the Wagner’s facilities for activities other than lectures. The Northwest News described the rise of amateur photography in Northwest Philadelphia and how the Photographic Society, organized under the auspices of the Wagner, spurred the movement. Thomas L. Montgomery, photography enthusiast and also librarian of the Wagner, was the founder and president of the society. The Society was organized in an effort to elevate the standard of amateur photography in Philadelphia. Making use of the Wagner’s darkroom, the Society held bimonthly meetings on the first and third Saturday of each month. The meetings were open to the public and each photographer was expected to have five slides produced for exhibition. Widely advertised in all of Philadelphia’s newspapers, these meetings became popular among the growing Philadelphia population.[20] The Wagner successfully used the photographs and the lantern slide collection to sell the Institute to the public.[21] The popularity of the Wagner’s lecture series continued to rise. In 1893 alone there was an estimated 21,000 people who attended 127 lectures.[22]

During 1890 to 1918, nearly every lecture at the Wagner Free Institute of Science was illustrated by “lantern slide views.” This almost thirty-year span was the peak of the Institute’s use of new media technology. Towards the turn of the century, a fundamental appeal of the lectures was the lore of the exotic. Photographic representations of distant lands were illustrated by lantern to demonstrate different cultures, geography, and various engineering feats. Travelogues became immensely popular in the early twentieth century, as they offered the opportunity for the public to glimpse far off lands from the comfort of their own city. The photographic image had become ubiquitous in society and in 1895 the arrival of motion pictures opened up a whole new way of documenting the natural world. In 1906 the Wagner started advertising evenings of travelogues that blended lantern slide presentations with motion pictures. Travelogue cinema became the marketing tool of the Wagner and in 1915 a motion picture projector was installed in the lecture hall. Though the cinema eventually eclipsed the lore of the magic lantern, the once new media played a central role in the development of the lectures at the Wagner Free Institute of Science.

Gallery of images showing the lecture hall at the Wagner Free Institute from 1900 to the present day:



1. Paul Young, “Media on Display: A Telegraphic History of Early American Cinema,” in New Media: 1740-1915, ed. Lisa Gitelman, (Cambridge: MIT Press, 2004), 233.
2. Untitled Article in Philadelphia Inquirer, January 11, 1861, found in Scrapbooks of the Wagner Free Institute of Science, 89-040 vol.2. p. 26.
3. Annals, 182.
4. Laurent Mannoni, The Great Art of Light and Shadow (Devon: University of Exeter Press, 2000).
5. Ibid.
6. Ibid., xxviii.
7. Charles Musser, The Emergence of Cinema: The American Screen to 1907 (Berkeley: University of California Press, 1994), 36.
8. Ibid.
9. Thomas L. Hankin, Instruments and the Imagination (Princeton: Princeton University Press, 1995), 66.
10. Annals, 202.
11. The Annals of the Wagner Free Institute of Science use the words “stereopticon” and “lantern” interchangeably. For the remainder of this discussion I will use the general term lantern when discussing the instrument.
12. From advertisement cards and clippings found in Coll. 89-040 Scrapbooks of the Wagner Free Institute of Science, 89-040 vol.2, Box 1.
13. Annals, 232.
14. Steven Conn, Museums and American Intellectual Life
15. Annals, 252.
16. Annals, 257.
17. Annals, 263.
18. Annals, 263-4.
19. Untitled Clipping, Philadelphia Evening Bulletin, 1879, found in Annals, p. 305.
20. “Knights of the Camera in Northwest Philadelphia”, The Northwest News, October 9, 1891. From, Scrapbook Vol. 1, 89-0401, Box 1.
21. From Philadelphia Evening Bulletin clipping, October 1892, Scrapbook, Vol.I , Box 1.
22. Scrapbook Vol. 1, 89-040, Box 3.