4 EDITOR'S PREFACE 



known as a disciple. The subjects of these sketches should all be 

 chosen from the list of those no longer living. While no one can 

 say which of all these is greatest, the fifteen should be chosen from 

 among the great. Benjamin Franklin, whose name comes to the 

 front at the first, was omitted, as his biography was already pro- 

 vided for in another volume in the same series. Simon Newcomb 

 and William Keith Brooks, men with undisputed place in the 

 first rank, were added, as they passed from earth while the vol- 

 ume was nearing completion. 



At the request of Mr. Holt, the present writer, as a labor of love, 

 undertook the compilation of these records. He is responsible 

 for the choice of subjects, and for the choice of authors, but the 

 pressure of work forced him to stop at that point, and to place 

 the editorial work in the more competent hands of Dr. Edwin E. 

 Slosson, with whom all further responsibility in this volume rests. 



But before laying down his pen, a few general considerations 

 rise to his attention. 



This volume constitutes a part of the scientific record of the 

 republic for a hundred years. It is the history of struggles in a 

 new country, without great libraries, great museums or great uni- 

 versities. It represents self-help and self-reliance to a greater de- 

 gree than would be shown in a parallel volume in any other land. 

 It shows the rise of observation and of knowledge derived from 

 travel, before that arising from experiment, or that deduced by 

 analytical reasoning. It shows the early charm of "the land where 

 nature is rich, while tools and appliances are few, while of tradi- 

 tions there are none." With this, no doubt, is associated the charm 

 of loveableness, characteristic of so many of these men, who 

 studied nature because they loved her. With all this, too, theirs 

 were uneventful lives, as we measure life in the stress of modern 

 industrial development. Leaving aside Benjamin Thompson, 

 whose history was wholly unique, nothing startling happened to 

 any one of them. None of them gained or lost great wealth. 

 None of them was elected to the Senate; none of them led embat- 

 tled hosts to victory, and none took part in any form of public 

 melodrama which would make his name known in the theaters 



