I had been looking for my gg-grandmother, Martha. A NY town clerk told me her name on the death record, though hard to read, was Mathews. After 10 fruitless years, a county historian recognized the name as Marthers, and through that clue I found Martha's father's will, listing her children and their location. (The grown children had moved after her death from NY to MI and WI.) Still, no further luck with the Marthers family anywhere.
Then at the end of one day researching at the library in Orlando FL, I had finished what I came to do and wandered aimlessly through the stacks of family histories, just to kill time until our group left. A fat book on "Mather" jumped out at me. It fell open to Addenda, and the first listing there was Augustus Mather, Martha's father, and his family. I now have 9 more generations of Mathers and a connection to the famous Puritans, Cotton and Increase Mather of Mass. Bay Colony! Ancestral help, or just great luck...?