My great grandfather Benjamin Best was listed in the 1830 and 1850 census INDEXES for Fairfield County, SC, but not in the 1840 index. I checked the actual census and found him there. The name was a little hard to read but he, the other family members, and their ages, were exactly as they should have been. MORAL: the indexes save time but there is no substitute for the primary document(s). This example was easy to figure out but I expect people could be easily missed when you rely just on indexes. Crawford Best