. >> the last document that we read is one from a guy named reverend john lee watson, who actually livedsylvania. he sent his own version in the form of a letter to the editor to the boston gazette, saying that it was his relative, captain john pulling, who actually hung the lanterns in the old north church. >> that's another secondary source because reverend watson wasn't an eyewitness either. having looked at the documents, next step is to hunt inside the church for clues. as bob showed me around, i asked him, "why is it important to question when and who wrote a historical document?" >> i think it's really important for us to recognize that history's not something which just comes down to us from on high or is a magical fixed thing that happened in the past. history is really stories that we've constructed from evidence that we have of what happened in the past. those stories can change and differ as we get new evidence. >> some of that new evidence is on a wall near the front of the church. it's a plaque that says robert newman displayed the lanterns. >> this was actually placed here