CHAPTER IV.

Birth and education of Sir John Herschel--Honours at Cambridge--First publication--Continues his scientific studies--His numerous literary contributions--His devotion to his father's reputation--The forty-foot telescope--Herschel's observations on the double and triple stars--On the refraction and polarization of light--Catalogue of nebulae and star-clusters--Voyage to Cape Town--Letter to Miss Herschel--Study of the southern heavens--Return to England--Distinctions conferred upon him--His "Familiar Lectures on Scientific Subjects"--His description of volcanoes and earthquakes--Continual changes in the configuration of the earth--Violent earthquakes--Phenomena of volcanic eruptions--In Mexico--In the island of Sumbawa--Herschel's theory of volcanic forces--His character