PREFACE. vii 



Where for the sake of clearness it has seemed desirable to the editors 

 to insert a word or two in a footnote or in the text itself, the addition 

 has been indicated by enclosing it within square brackets [], a sign 

 which is otherwise used only in the formulae. 



A sketch of the life and estimate of the work of Professor Gibbs, 

 by one of the editors, is placed at the beginning of the first volume. 

 It is taken, with some additions, from the American Journal of 

 Science, September 1903. 



HENRY ANDREWS BUMSTEAD. 

 RALPH GIBBS VAN NAME. 



YALE UNIVERSITY, 

 NEW HAVEN, 

 October 1906. 



