See book "Postal History of Delaware" by Harvey C Bounds  
Publisher: Newark, Del., Printed by Press of Kells, ©1938

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Search World Cat <http://www.worldcat.org/search?qt=worldcat_org> to find a 
library which holds this book.


According to History of Delaware by J. Thomas Scharf pub 1888
these were the postmasters up to that time:

Josiah Selby Nov. 7, 1848 [Postal History of Delaware, p37,38]
Isaac McCabe
William S. McCabe 
E. M. McCabe
W. G. Davis
John W. Poole
Miss Annie Dukes