On board, Ezra makes observations from the captain's chair and Cate talks to him about the floating gas station, what the dials and gauges on the dashboard mean, and her home-brewed "[[wikipedia:kykeon|kykeon]] [[wikipedia:kombucha|kombucha]]." She tells him that she relies heavily on landmarks and lights, as compasses don't work well on the Echo. She tells him about the landmarks they've passed so far – Duck Island, the Lighthouse, and the Story Cliff. Noticing they should have passed Dinosaur Rock by now, but haven't, she sends Ezra to the map room to help Will update the charts.
On his way there, Ezra records more sounds. He encounters Conway, who tells him that he doesn't use maps, and instead remembers roads using landmarks or asks for directions. After walking past Shannon, who is trying out Clara's [[wikipedia:theremin|theremin]], Ezra finds Will who asks him for information to update the charts, since locations on the river often end up shifting in position. As a thank you, he offers a selection of old maps charting underwater islands.
=== Sailing down the Echo ===
=== Sailing down the Echo ===
{{expand}}On the way back to the tugboat, Shannon can meet a number of nameless characters – a family of five traveling all night, a guitar player on a floating bicycle, a flower salesman on a raft, a painter of shipwrecks. Eventually, she shuts the motor off and floats in silence.
=== Sam & Ida's ===
{{expand}}Shannon reconvenes with the Mammoth crew at Sam & Ida's, a floating, stilted restaurant on [[Lake Lethe]]. Cate, Will, and Junebug sit at a table deciding on their to-go order for Clara, who is back on the ship practicing for her concert. Shannon talks with Johnny and Ezra off to the side, who are playing a crane game, and tells them that Conway either left or was taken. She returns to the table to order food while Ezra plays for either a stuffed octopus, a bag of clam shells, a cowboy hat, or a pair of headphones. <!-- IDA: Yes, it's all about ''patience'' down here. Everything grows more slowly in the dark. -->Johnny and Ezra look at the restaurant's plastic food display and discuss Ezra's parents, and how he misses them. Shannon talks with Cate and Junebug about how Conway left his truck to her, and vows to complete his delivery. [[Ida]] appears and Shannon orders her a seafood dish – "something primordial." Ida tells Ezra the story of the [[wikipedia:shellac|shellac]]-covered dinner preserved on the table, how she and her husband [[Sam]] were inspired by two divers with bottomless appetites who ate there, which became a turning point in their career. <!-- SAM: Just passing through. Hey, aren't we all? -->Down below, Sam returns from a diving expedition with a small eel. He muses about having listened to the divers boast and attempt to one-up each other in telling grand fishing stories, and having made a mental map of routes which have now helped him catch fish for the restaurant for 15 years. He says, however, he is afraid he could die any day following a false story told by the divers for the sake of winning their competition. A he walks up the stairs, Ira brings out the food, and the group prepares to leave. Shannon walks back to the boat as [[Emily, Ben, and Bob]] float by, playing "[[This World Is Not My Home]]."
=== Sailing down the Echo ===
<!-- sailing: As the ''Mammoth'' sails on, Will notes a swirling patch of garbage which he calls the Cluttered Place -->{{expand}}. He tells a story about the floating wood scraps visible in the eddy, and their origins from either a shuttered canoe rental shop or beauty school run by sisters named Cassie and Paula, after the constellation [[wikipedia:Gemini (constellation)|Gemini]].
=== A neighborhood ===
{{expand}}<!-- JUNEBUG: When I met you — when we met, we were nothing, just these little gray shadows. And we grew, and filled in, and ... but we did all that together. -->The tugboat arrives at a small houseboat neighborhood. From the deck of the ship, Clara plays a [[Music for Rivers|solo theremin piece]], using the sounds Ezra recorded. Junebug and Johnny reminisce about a previous performance of Clara's at a flower shop where Cyrano opened for her. The two discuss Ezra, who seems directionless and lost, and Johnny brings up the possibility of having him join them. Junebug worries what this development could do to their relationship that they built together, from simple robots to unique individuals, but soon reconsiders, saying they would both appreciate his company, and considers teaching him to play the drum machine with them. As the memory of Clara's flower shop concert come to an end, so does her performance on the Echo, and the crew members return to the boat.
=== Sailing down the Echo ===
{{expand}}Will reminisces about a photographer who took his portrait only to have her film washed away in the water; he says it's no shame to be forgotten. The ''Mammoth'' arrives at the Silo mail stop. The passengers, either two or one lighter than planned (depending on whether Conway's dog went with him or stayed with the group), disembark. Will narrates the scene::''They couldn't seem to get that old truck started up again, but we managed to roll it off the barge with only a minor scrape or two. At the last minute, Clara decided to travel with them for a while. Cate and I said goodbye to our friends — new and old — and ''The Mucky Mammoth'' rumbled on down the Echo.''
=== Silo of Late Reflections ===
{{expand}}The group stands at the bottom of a large spiral staircase. Realizing it's the only path available, with no way to bring the truck along, they begin to unload the haul, preparing to complete the delivery on foot.
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