Chapter II: On the Refraction of Light

Nature of refraction--Illustrated by experiments--Angle of refraction--Familiar experiments illustrative of refraction--Refraction explains the causes of many curious and interesting phenomena--Its effect on the heavenly bodies--On the twilight--Illustrated by figures

_page_ 41-53.

EXTRAORDINARY CASES OF REFRACTION IN RELATION TO TERRESTRIAL OBJECTS.

Extraordinary appearance of the coast of France from Hastings--Appearance of a ship seen by Captain Colby, beyond the coast of Caithness--Scoresby’s view of his father’s ship when beyond the horizon--Phenomenon near the Himalaya mountains--Bell Rock light-house--Summary statement of the diversified effects of refraction--Reflections on the beneficent and diversified effects produced by the law of refraction--It increases the length of the day, particularly in the polar regions--Is the cause of that splendour which appears in the objects around us--Quantity of refraction in respect to terrestrial objects, and its utility--Its effects may be more diversified in other worlds

_page_ 53-63.

CHAPTER III.

ON THE REFRACTION OF LIGHT THROUGH SPHERICAL TRANSPARENT SUBSTANCES, OR LENSES.

Refraction the foundation of optical instruments--Various forms of lenses--_Parallel_, _converging_, and _diverging_ rays--Illustrated by diagrams--_Concave_ lenses, their effects, and how to find their focal distances--IMAGES formed by convex lenses--Illustrated by experiments--Principles in relation to images formed by lenses--Their magnifying powers, &c.

_page_ 63-75.

REFLECTIONS DEDUCED FROM THE PRECEDING SUBJECT.

Property of the rays of light in forming _images_ of objects--Wonderful results and discoveries which have flowed from this property--in relation to our knowledge of the scenery of the heavens and the minute parts of nature--and of our views of the attributes of Deity

_page_ 75-80.