You may not have realized it, but there's a Golden Rule of Genealogy: Leave for your descendants what you wish your ancestors had left for you. You've spent years digging up data and stories to breathe life into the grandparents and great-grandparents who've made your existence — and your children's — possible. But what are you doing to ensure your family's legacy will be around after you're gone?

Here's something else to ponder: What if a long-ago relative started climbing your family tree, but all his efforts got pitched because he didn't take measures to ensure his opus would outlast him? Surely you aren't the first person in all those generations to investigate the family's history. Take, for example, this letter I discovered tucked away in a special collection of the University of Virginia Library <www.lib.virginia.edu> in Charlottesville: