Page:The wonders of optics (1869).djvu/140

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132
THE WONDERS OF OPTICS.

reversed again by the arrangement of small lenses next to the eye.

Fig. 32.—Magnifying Property of Convex Lenses.

Double concave lenses produce effects which are just the reverse of those we have been considering. Instead of increasing in thickness from the edges to the centre, they follow the contrary plan, and increase from the centre to the edges. Consequently, instead of the rays meeting at the focus, they diverge from each other, and gradually spread out, as shown in fig. 33.

Fig. 33.—Diminishing Effect of Concave Lenses

The above figure shows the path of the rays proceeding from the vase, and meeting the eye at such an angle