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An illustration depicting an infinite sequence of tangent circles with the radius converging to zero. This is often called a Hawaiian earring.

Infinite Tangent Circles

An illustration depicting an infinite sequence of tangent circles with the radius converging to zero.…

"If the object a be placed obliquely before the convex mirror, then the converging rays from its two extremities falling obliquely on its surface, would they prolonged through the mirror, meet at the point c, behind it. But instead of being thus continued, they are thrown back by the mirror in less convergent lines, which meet the eye at e, it being, as we have seen, one of the properties of this mirror, to reflect converging rays less convergent than before." -Comstock 1850

Curved Image

"If the object a be placed obliquely before the convex mirror, then the converging rays from its two…

"A double convex lens of crown-glass may be combined with a plano-convex lens of flint-glass so as to overcome the dispersive effect for some of the colors without overcoming the converging effect." -Avery 1895

Achromatic Lens

"A double convex lens of crown-glass may be combined with a plano-convex lens of flint-glass so as to…

"Thus the pencils of converging rays, are rendered still more convergent by their passage through the lens, and are therefore brought to a focus nearer the lens, in proportion to their previous convergency." -Comstock 1850

Converging Rays and a Double Convex Lens

"Thus the pencils of converging rays, are rendered still more convergent by their passage through the…