Kircher also described how images of objects could be projected by means of the light of a candle. Through this system various images were exhibited in a darkened chamber. But Kircher evidently was not satisfied with this method, for no illustration of it appeared in the first edition of his book. The reason is obvious. A candle could provide only enough illumination for the faintest shadows. Kircher wrote that those objects which need only a fraction of the sun’s light can be shown by a candle in a small room. Two methods for this were indicated: (1) with a concave mirror reflecting the images and (2) projecting the image through a lens. It was noted that the better single method was through the lens. A combination of the two provided the most light. Kircher remarked that he had read in a history of the Arabs that a certain king of Bagdad used a mirror to work wonders in order to deceive the people. He also pointed out that some men had used mirrors to project into dark places what the ignorant thought were devils. The chief problem in Kircher’s day and for centuries afterwards was to provide sufficient light. The final solution did not come until electric light was introduced. Probably Kircher’s most efficient projection was one in which the sun was used as the source of light. Even in the early part of the 20th century arrangements were used which hooked up the sun with the magic lantern because it was thought that the results were even better and cheaper than those obtained with electric light. Kircher’s sun magic projector used a real optical system which is fundamental even to this day. There was first the source of light, then a reflector and the object, and the projected image. The effects, of course, would be most startling in a darkened room. Kircher also showed how shadows of any type of figure could be thrown onto a wall or screen through the same method. In those days when there was much secret correspondence and keen interest in various forms of cipher, many of Kircher’s readers were glad to note how the magic lantern could be used for such a purpose. At that time people would not, it was believed, detect that the letters in such a system were simply backwards and upside down. The message could be read easily by projecting images of the letters. The same result could be had by turning the paper upside down and holding it before a mirror. After listing these many diverse uses of the magic lantern system Kircher thought it well to conclude his book lest he be charged with “meandering” endlessly on a subject which some would consider trivial. Kircher said, “We leave all these to the talented reader for further refinement. A word to the wise is sufficient. Innumerable things could be said concerning the application of this device but we leave to others new material of invention and lest this work grow too long we cut off the thread of discussion about these devices.”