There is an excellent popular account of Galilei’s life and work in the Lives of Eminent Persons published by the Society for the Diffusion of Useful Knowledge; students who want fuller accounts of Galilei’s life should read Gebler’s book and the Private Life, which have been already quoted, and are strongly recommended to read at any rate parts of the Dialogue on the Two Chief Systems of the World, either in the original or in the picturesque old translation by Salusbury: there is also a modern German version of this book, as well as of the Two New Sciences, in Ostwald’s series of Klassiker der exakten Wissenschaften.
Chapter VII.—For Kepler’s life I have used chiefly Wolf and the life—or rather biographical material—given by Frisch in the last volume of his edition of Kepler’s works, also to a small extent Breitschwerdt’s Johann Keppler. For Kepler’s scientific discoveries I have used chiefly his own writings, but I am indebted to some extent to Wolf and Delambre, especially for information with regard to his minor works. The portrait is a reproduction of one by Nordling given in Frisch’s edition.
The Lives of Eminent Persons, already referred to, also contains an excellent popular account of Kepler’s life and work.
Chapter VIII.—I have used chiefly Wolf and Delambre; for the English writers Gascoigne and Horrocks I have used Whewell and articles in the Dict. Nat. Biog. What I have said about the work of Huygens is taken directly from the books of his which are quoted in the text; and for special points I have consulted the Principia of Descartes, and a very few of Cassini’s extensive writings.
There is no obvious book to recommend to students.
Chapter IX.—For the external events of Newton’s life I have relied chiefly on Brewster’s Memoirs of Sir Isaac Newton; and for the history of the growth of his ideas on the subject of gravitation I have made extensive use of W. W. R. Ball’s Essay on Newton’s Principia, and of the original documents contained in it. I have also made some use of the articles on Newton in the Encyclopaedia Britannica and the Dictionary of National Biography; as well as of Rigaud’s Correspondence of Scientific Men of the Seventeenth Century, of Edleston’s Correspondence of Sir Isaac Newton and Prof. Cotes, and of Baily’s Account of the Revd. John Flamsteed. The portrait is a reproduction of one by Kneller.
Students are recommended to read Brewster’s book, quoted above, or the abridged Life of Sir Isaac Newton by the same author. The Laws of Motion are discussed in most modern textbooks of dynamics; the best treatment that I am acquainted with of the various difficulties connected with them is in an article by W. H. Macaulay in the Bulletin of the American Mathematical Society, Ser. II., Vol. III., No. 10, July 1897.
Chapter X.—For Flamsteed I have used chiefly Baily’s Account of the Revd. John Flamsteed; for Bradley little but the Miscellaneous Works and Correspondence of the Rev. James Bradley (edited by Rigaud), from which the portrait has been taken. My account of Halley’s work is based to a considerable extent on his own writings; there is a good deal of biographical information about him in the books already quoted in connection with Newton and Flamsteed, and there is a useful article on him in the Dictionary of National Biography. I have made a good deal of use in this chapter of Wolf and Delambre, especially in dealing with Continental astronomers; and for special parts of the subject I have used Grant’s History of Physical Astronomy, Todhunter’s History of the Mathematical Theories of Attraction and the Figure of the Earth, and Poynting’s Density of the Earth.
Chapter XI.—Most of the biographical material has been taken from Wolf from articles in various encyclopaedias and biographical dictionaries, chiefly French, and from Delambre’s Eloge of Lagrange. The two portraits are taken respectively from Serret’s edition of the Oeuvres de Lagrange and from the Academy’s edition of the Oeuvres Complètes de Laplace. Gautier’s Essai Historique sur le Problème des Trois Corps and Grant’s History of Physical Astronomy have been the books most used for my account of the scientific contributions of the various astronomers dealt with; I have also consulted various modern treatises on gravitational astronomy, especially Tisserand’s Mécanique Céleste, Brown’s Lunar Theory, and to a less extent Cheyne’s Planetary Theory and Airy’s Gravitation. For special points I have used Todhunter’s History, already referred to. Of the original writings I have made a good deal of use of Laplace’s Mécanique Céleste as well as of his Système du Monde; I have also consulted a certain number of his other writings and of those of Lagrange and Clairaut; but have made no systematic study of them.
Students who wish to know more about gravitational astronomy but have little knowledge of mathematics should try to read Airy’s Gravitation; Herschel’s Outlines of Astronomy and Grant’s History (quoted above) also deal with the subject without employing mathematics, and are tolerably intelligible.