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 of people gazed through it, and Galileo went on grinding new lenses—making rude telescopes (such as children might still make and use—could be led on to make spontaneously to-day). From that time the eye-projecting instrument makers multiplied in many lands, and at last from the nation of all others whe [sic] see quickly and clearly (that is, the French) a man arose—Daguerre—who projected the eye so fully that every book on elementary physiology describes the eye by describing his invention, the photographic camera.

Even if the question is considered in detail, and the very latest discoveries with regard to the life taken into account, the fact of projection is driven home. We will cite one out of many. Photographers found that light will break up iodide of silver, and that with the aid of iodide of silver, therefore, they could get negatives; but nature had got negatives by the action of light on eye pigment for aeons. Many years after the silver salts began to be used in photography—in 1876—Ball found that light breaks