had an uncommonly good memory; but occasional comments by the author show 

 that he had also bales and boxes of papers, drawings, and artifacts of an active life- 

 time to refer to. Limited only by his failing eyesight, he used his reference mate- 

 rials with skill and candor. Even when his details can be disputed, which is seldom, 

 his broader strokes paint a likeness that lets us see a real person where there would 

 be otherwise only a name. 



The reader can hardly fail to find new insights, previously unrecognized 

 relationships amongst people and events, and occasionally — as when ebullient 

 Jacob Perkins or sagacious Bryan Donkin step out of the page to confront the reader — 

 sheer delight. 



I have selected for publication those parts of the story that are pertinent to the 

 history of technology, believing that they will be useful as source materials in the 

 many studies that ought to be made of the technical history of this period. The 

 articles describe events that the author had direct knowledge of. Second-hand 

 narrative or historical summary are retained only when they contain information 

 not otherwise available, or when editorial interpolation would do violence to the 

 author's narrative. Family history, of which a great deal exists in the unpublished 

 volumes mentioned above, has been left for biographers of the several prominent 

 members of the Sellers and Peale families. 



These reminiscences were written over a period of nearly 15 years, and for all 

 their essential charm and freshness they were sometimes rambling and repetitious; 

 no detectable plan or order was followed in their preparation. Therefore, the arti- 

 cles, and occasionally passages within an article, have been rearranged to give very 

 roughly a chronological sequence. 



Editing within each article has been held to a minimum, and changes and omissions 

 have been noted in the text. Marks of elision have not been used generally to open 

 and close passages from the typescript volumes in the American Philosophical So- 

 ciety Library because the typescript is made up of a series of letters that really has 

 neither beginning nor ending. 



Because the work is presented as source material, 1 have tried to preserve its meaning 

 by not tampering with the author's style. I have spelled out abbreviations, corrected 

 the spellings of names, and increased the number of paragraphs greatly, because the 

 author paid little attention to such things. Grammatical changes, which have been 

 made only when necessary, have been bracketed. 



Footnotes that appear more bibliographic than interpretive are intended to sug- 

 gest further studies. I have assumed the risk of annoying some readers by tedious 

 annotation in the hope that others will make use of the information and will help to 

 fill in some of the larger gaps in our knowledge of this field and this period. 



I have been helped in every stage of the work by many individuals who have 

 generously supplied encouragement, information, or pictorial materials, as the 

 occasion demanded. 



My first thanks are to Jo, my wife, who has submitted with patience and under- 

 standing to the tyranny of a work-in-progress in our home. Two former colleagues 

 have been particularly helpful: Robert P. Multhauf encouraged me to undertake 

 this work; John H. White put his extensive detailed knowledge and records of early 

 railroads at my disposal, and he gave freely of his time in reading the manuscript, 

 in discussing points not clear to me, and in locating materials for my use. 



