Jacob leaves the house feeling disappointed. It's a wreck and the other kids on the island that are his age don't even like him.
Back at the bar, Jacob asks Dad about Grandpa, and Dad admits that he "gave up trying to understand [Grandpa] a long time ago" (4.18).
Dad says that Grandpa was always leaving without telling the family exactly where he was going.
Once, they found a letter from a woman to Grandpa: "I love you, I miss you" (4.40), it said. Understandably, Dad and Susie thought he might be having an affair.
Jacob doesn't want to give up just yet, so he heads to the museum to talk to Martin Pagett, the curator, about the island.
Looking for Martin, Jacob is scared when he finds a display case holding the blackened corpse of Cairnholm Man.
Martin tells him that it's a 2700-year-old body found in the bog. Yikes.
They suspect that Swamp Thing sacrificed himself to the gods, because they believed the bog was an entrance to heaven, and the way to get in was to sacrifice themselves. (We hope Bruno Mars doesn't try the same thing next time he gets locked out of heaven.)
Jacob changes the subject to the old children's home. Martin has a succinct answer when Jacob wonders about the inhabitants' whereabouts: "They're dead" (4.81).
He says that his Uncle Oggie knows everything about the island, so they go to pay him a visit.
Oggie says all the people there were weird (dare he say, peculiar?) and they were bombed on September 3, 1940.
Dun dun dun… That's the date Grandpa uttered in his final words.
Oggie says there was one survivor that day: Jacob's grandfather.
After chatting with dad at the bar, Jacob tries to go to sleep, but he can't stop wondering if this Miss Peregrine character was Grandpa's "other woman" (4.138).
Jacob realizes that the postmark on Miss Peregrine's letter is from way after 1940, so she must still be alive.
He falls asleep, and when he wakes up, a huge bird is perched on his dresser.
Jacob screams for dad, who runs in and says it's a "peregrine falcon" (4.148). Gasp.
That's one weird coincidence too many, and Jacob decides that he has to return to the house.