Way back in October 2000, Marcia Melnyk did a wonderful article in Family Tree Magazine that reminded us what to look for in every document we find:
Leave no stone unturned. Many types of records provide clues that are often overlooked. Take what I call the “Doberman” approach to your genealogy research: Latch on to a fact and don't let go until you've gotten everything out of it. Squeezing every single scrap of information from a record as a clue to other research will pay big dividends. “Ask” every document these questions:
• Why was the document created in the first place?
• Are you looking at the original or a copy?
• To whom does the document pertain?
• How close to the original event was the document created?
• Who are the witnesses, informants or other persons mentioned in the document?
• Are any family relationships stated or implied?
• Did the person executing the document sign with a signature or mark?
• Is the information reliable, usable, or simply a clue to further research?
• What's the full citation for the document?
If we'll keep these questions in mind, we will the MOST out of every document we locate!