Giambattista della Porta's very popular and influential "Magia Naturalis" helped popularize the camera obscura. In the 1558 first edition of the book series, Della Porta advised to use a convex mirror to project the image onto paper and to use this as a drawing aid. The 1589 second edition added a "lenticular crystal" or biconvex lens to the setup. In this edition, Della Porta also described a way to scare people at night by projecting a scary image lit by torches in one room onto a white sheet or other surface in the dark nascent room. In a more elaborate daytime use of the camera obscura Della Porta proposed to project hunting scenes, banquets, battles, plays, or anything desired on white sheets. Trees, forests, rivers, mountains "that are really so, or made by Art, of Wood, or some other matter" could be arranged on a plain in the sunshine on the other side of the camera obscura wall. Little children and animals (for instance handmade deer, wild boars, rhinos, elephants, and lions) could perform in this set. "Then, by degrees, they must appear, as coming out of their dens, upon the Plain: The Hunter he must come with his hunting Pole, Nets, Arrows, and other necessaries, that may represent hunting: Let there be Horns, Cornets, Trumpets sounded: those that are in the Chamber shall see Trees, Animals, Hunters Faces, and all the rest so plainly, that they cannot tell whether they be true or delusions: Swords drawn will glister in at the hole, that they will make people almost afraid."