This is one of the earliest and richest collections of Pennsylvania genealogies and one which is still considered reliable. It is concerned primarily with families which, for the most part, settled in the extreme regions of colonial Chester County, in that portion set off in 1728 to form Lancaster County, an area where source material is notoriously scarce. Of the 60 families included in the work, fully two-thirds are of Scotch-Irish ancestry and most, though not all, are brought down to the late 19th century. More than 3,000 names are found in the index, many with multiple references.
The following is a list of the families treated: Ainsworth, Allen, Alricks, Anderson, Andrews, Awl, Ayres, Barnett, Beatty, Boas, Bomberger, Boyd, Bucher, Cowden, Craig, Crain, Curtin, Denny, Dixon, Egle, Elder, Espy, Ferguson, Fleming, Forster, Fulton, Galbraith, Gregg, Greenawalt, Hamilton, Hays, Hoge, Keller, Kendig, Kunkel, Linn, Lobingier, Lyon, Maclay, McCormick, McNair, Muller, Murray, Neville, Orth, Parker, Roan, Robinson, Rutherford, Simonton, Stewart, Swan, Thomas, Wallace, Weir, Wiestling, Wiggins, Wilson, and Wyeth.