Overlapping like the scales of a snake.
The complexity of the chute Juliette and her people use in digging the tunnel is compared to the scales of a snake. The narrator says, "There were wheels and gears beneath the plates on the other side that overlapped like the scales on a snake." The convolution of the chute shows the challenges faced by Juliette in getting access to Silo 18.
Smooth like melted candles
The narrator compares the end of the silo-jugged walls to a smooth candle. The narrator says, "A first row of rebar hung jagged overhead, the ends smooth like melted candles where she'd taken a blowtorch to them." The simile shows a glimpse of hope for Juliette and her team as they Endeavour to dig a long tunnel to connect Silo 17 to Silo 18. The smoothness of the walls' jugged ends implies Juliette is almost accomplishing her dangerous task.
Cool, like the deep mines
The depth of the tunnel dug by Juliette and her team is likened to the deep mines. The narrator says, "The air beyond the generator was cool like the deep mines." The simile is a manifestation of how dangerous the task for Juliette is. Juliette wants to help her people escape the underground silo to the Earth's surface. However, the task is challenging because it involves digging a tunnel that goes deep to avoid suspicion by the authorities.
