Rod Library has just added a copy of the "Atlas of Black Hawk County 1926" to its Digital Collections. This book provides a unique look at our county in a different era where the township assumed great importance in local government.
The ideal civil township was six miles square, and the township held elections, repaired roads, and gave relief to the poor. In addition to the detailed township maps in this volume you can find farmers' directories which detail the owner (or renter) of each parcel of land, his wife, children, and how many years he had lived in the county.
See this book at: http://cdm.lib.uni.edu/cdm4/browse.php?CISOROOT=/abhcty