Page:The wonders of optics (1869).djvu/124

116 eye in such a way as to appear to proceed from a point beyond the mirror,. In the same manner the rays reflected from the chin appear to take their origin from the point. If, on the other hand, we place ourselves at a distance from the principal focus, we shall produce a reversed and diminished image of our face. This image is not illusory, like the preceding ones, but is real, and may be received upon a screen, as shown in fig. 23.

We may easily follow the path of the rays as shown in the figure, and we shall see that the rays forming the images of the church-tower and the terrace below, cross at a certain point.

Convex mirrors produce precisely opposite effects, and give a diminished image instead of a magnified one, as may be perceived on examining fig. 24.