AUTHORS CONSULTED. xxvii 



TYNDALL . ; . : . . Natural Philosophy. On Light. On 



Sound. Half-hours with Modern Scien- 

 tists. Heat a Mode of Motion. Faraday 

 as a Discoverer. The Glaciers of the 

 Alps. 



VENTURI . . v . Ouvrages Physico - Mathe'matiques de 



Leonardo da Vinci. 



WRIGHT . . . . Ice Age in North America. 



WALLACE . . v . Natural Selection. Darwinism. Island 



Life. 



WATTS . . . . . Dictionary of Chemistry. 



WHEWELL . \ . ' " * . History of Inductive Sciences. 



WILLIAMS, GREVILLE . . Manual of Chemical Manipulation. 



WOLLASTON. . . .. On Dispersion. 



XENOPHON . . , . . Economics. 



YOUNG. . . VJVJH Lectures on Natural Philosophy. 



