IV 



PREFACE. 



thusiastic love of Nature, which carried them over every ob- 

 stacle in the pursuit of their chosen study. 



Nearly all of the biographies appeared originally in the 

 Popular Science Monthly, in which magazine such accounts 

 have long been considered by many of its readers one of its 

 most interesting features. The accompanying portraits, as will 

 be seen, are in every instance well authenticated. In collecting 

 the materials for the Monthly no effort was spared to reach 

 the most trustworthy sources of information. Surviving rela- 

 tives when accessible, the records of educational institutions, 

 public documents, and published biographies in the few cases 

 where these existed, were freely consulted, especial care being 

 taken to verify names, dates, and other important facts. The 

 accuracy thus secured in the first instance has been made more 

 perfect by a thorough revision of the matter for this volume. 



The number of biographies included in the book is limited 

 to fifty. Of course it is not claimed that these comprise all the 

 names in American science that are entitled to a like distinc- 

 tion ; but beginning with the time of Franklin, prior to which 

 we have found no record of the systematic pursuit of science 

 by any one in this country, the plan has been to present the 

 various personages in the order of their birth, making the list 

 as complete as possible as far as it went. This brings it down 

 to about the year 1810, the working period of many of those 

 included thus falling within the present century. Should the 

 book be found of sufficient interest to warrant the venture, a 

 second volume on a similar plan may follow. 



I am indebted to Mr. W. H. Larrabee for the preparation of 

 the sketch which opens the volume. This involved a long and 

 painstaking search through a very considerable literature, and 

 so far as I know it is the first systematic account of what 

 Franklin did in science that has appeared. My acknowledg- 

 ments are also due to Mr. F. A. Fernald for valuable aid in the 

 work of revision and in seeing the book through the press. 



W. J. Y. 

 NEW YORK, January 12, 1896. 



