I am also researching the Congdons.
My ggggrandfather was James Congdon of England. Had Samuel b Feb 1818 Devonport, Plymouth, Devon, England and possiblely female b abt Feb 1794 who lived to be 112 years old. Samuel moved to Newfoundland and married Rachel Martin. Any information in your book on those people. Thanks-Shirley firstname.lastname@example.org