huge assortment of original turn of the century antique american "magic lantern" projector slides designed and fabricated by the mcintosh batter & optical company, chicago, il. the delicate transfer lithograph glass slides offer a vast array of biological specimens depicted on a microscopic level. the glass slides contain circular cardboard "fillers" with individualized labeling. found in storage. originally used in an old c. 1900's chicago area science classroom. the first known record of what might portray the idea of projecting an image on a surface is a drawing by johannes de fontana from 1420. the drawing was of a nun holding something that might be a lantern. the lantern had a small translucent window that contained an image of a devil holding a lance. leonardo da vincialso made a similar sketch in 1515. these drawings are likely to have inspired the creation of the earliest image projector, a device called a magic lantern. in the 17th century, a the first magic lantern was developed. with pinhole cameras and camera obscura it was only possible to project an image of actual scene, such as an image of the sun, on a surface. the magic lantern on the other hand could project a painted image on a surface, and marks the point where cameras and projectors became two different kinds of devices. there has been some debate about who the original inventor of the magic lantern is, but the most widely accepted theory is that christiaan huygens developed the original device in the late 1650's. huygen’s device was even referred to as the “lantern of fright” because it was able to project spooky images that looked like apparitions. in its early development, it was mostly used by magicians and conjurers to project images, making them appear or disappear, transform from one scene into a different scene, animate normally inanimate objects, or even create the belief of bringing the dead back to life. in the 1660's, a man named thomas walgensten used his so-called “lantern of fear” to summon ghosts. these misuses of this early machine were not uncommon. in fact, a common setup of the machine was to keep parts of the projector in a separate, adjoining room with only the aperture visible, to make it seem more magical and scare people. by the 18th century, use by charlatans was common for religious reasons. for example, count cagliostro used it to ‘raise dead spirits’ in egyptian masonry. johann georg schröpfer used the magic lantern to conjure up images of dead people on smoke. he staged routines doing this at his coffee shop in leipzig. he did this to scare people and make them think he was a good actor. schröpfer ended up going crazy and thinking he himself was pursued by real devils, and shot himself after promising an audience he would later resurrect himself. in the early and middle parts of the 20th century, a new type of low-cost projectors called opaque projectors were produced and marketed as toys for children. the opaque projector is a predecessor to the overhead projector. the light source in early opaque projectors was often limelight. incandescent light bulbs with halogen lamps taking over later. in the late 1950's and early 1960's, overhead projectors began to be widely used in schools and businesses. each slide measures approximately 3 1/4 x 3 1/4 inches. priced for the lot.