No one close to her shared her dread. Dovey wouldn’t hear it; her methods of self-preservation were fierce. And Cub was protected in his own way, unable to believe that this outpost of life that had landed in their custody was irreplaceable. She feared Preston would be the opposite, that he would feel the multitude of deaths too deeply, so she didn’t tell him everything. He brought home pictures of monkeys and tree frogs cut from magazines at school and taped them to his bedroom wall in elaborate collages, much like those his father had once assembled with pictures of Captain Fantastic and Jesus. With all his might Preston wanted to be a scientist and study animals. But in the lab Dellarobia listened to Ovid and Pete speaking hopelessly about so many things. The elephants in drought-stricken Africa, the polar bears on the melting ice, were “as good as gone,” they said with infuriating resignation as they worked through what seemed to be an early autopsy on another doomed creature. Gone, as if those elephants on the sun-bleached plain were merely slogging out the last leg of a tired journey. The final stages of grief. Dellarobia felt an entirely new form of panic as she watched her son love nature so expectantly, wondering if he might be racing toward a future like some complicated sand castle that was crumbling under the tide. She didn’t know how scientists bore such knowledge. People had to manage terrible truths. As she lay awake she imagined Ovid doing the same in his parallel bed, not so far away across the darkness, joined with her in the vigil against the cold. Because of him, she wasn’t alone.

Each morning by daylight she crossed the same distance from her kitchen door to Ovid’s camper, pausing there on her way to the lab to record the previous day’s high and low temperatures. He used these to estimate the rates at which butterflies were using up their fat reserves when they stayed quiet in the trees, versus warm days when they flew around. Too warm was just as dangerous as too cold, he said. Dellarobia felt like an accessory to the crime as she plotted the numbers each day, but it was one of her tasks. A special thermometer was attached to the camper by means of a metal arm extending from the passenger’s side window. She pressed the mechanism’s tiny buttons to reveal the day’s readings and then zero them out, a small thing to master but it pleased her to do it, like Preston with his watch. Ovid showed her how to make a graph from the two lines of dots, showing the high and low temperatures marching across the month with the survival zone for monarchs pressed narrowly between them.

It was the wavering pencil line on graph paper that first made her think of a high-wire act, and again now she pictured the man in a bowler hat with a white-painted face, expressionless, raising and lowering black-slippered feet in slow motion along his wire. Life in the balance. She couldn’t say where she had seen him, but it must have been on television, probably just a glimpse as Cub cruised past on his way to more conventional entertainments. The image was in her mind as she approached the camper. She was not on her way to work this morning, Ovid did not expect her to be in the lab on Saturdays, though he and Pete usually were. Today she’d pulled on her boots and coat in order to help Cub walk the fence line behind their house, at Hester’s request. She had decided to move the pregnant ewes over here. Cub had already taken Cordie and Preston over for his mother to babysit while they worked on the fence, but now he sat procrastinating in the kitchen, drinking a third cup of coffee and listening to Johnny Midgeon’s morning show while gathering his gumption for a hefty hike in the cold. Dellarobia felt agitated as always with her husband’s balky progress. To defuse her impatience, she went outside to take the morning’s temperature reading for her notebook, and that was when she saw Ovid Byron naked.

Just a glance. Not his face, it was from armpits to thighs, approximately. She turned away so quickly she nearly fell down in the mud, scarlet with embarrassment, heart pounding. How was she supposed to know he was in there? He was always up at dawn. The camper’s pleated curtains with their snap closures stayed permanently closed on the side facing her house. She’d grown used to his durable privacy, never noticing that the other side facing the mountains might be open. Of course he would want that view of the high ridge, which she took for granted. She stumbled toward the house, feeling faint. Feeling vile. A Peeping Tom. Had he seen her? It seemed unlikely. The thought was excruciating. Going to work, ever, seemed undoable if it involved any possibility of looking him in the eye again. His eyes were no part of the snapshot, only the long-waisted torso she could not erase, burned onto her retina. The coffee-colored skin, the surprisingly sculpted abdomen, the shadow line of tightly curled hair like a funnel cloud down the center of his chest, nearly touching down on the dark pubic ground. She wondered how she could have seen so much in a millisecond. She’d turned away before registering anything more than movement and a change of light on the smooth planes she only understood after the fact to be a body. Truly, she hadn’t seen what she’d seen. She was sure Cub would see guilt on her face when she entered the back door, scraping her boots, looking at the doorsill.

“Okay, let’s get this over with,” Cub said, not even looking at her. He rose from the table and pulled the olive-drab dead weight of his farm coat from the back of a chair. She felt unaccountably emptied out. Even this did not matter, then, that she had seen a man so important to her in his nakedness, a biblical act. She felt invisible.

She had failed to record the temperature, obviously. The notebook was still in her hand as they stepped out the kitchen door. She slid it quickly onto the junk table next to a flowerpot jammed with cigarette butts, a still life of her sins, before descending the two steps down from the back porch. What she wouldn’t give for a smoke right now. But that was the regular formula, wasn’t it? People always gave their lives for a smoke. Cub shivered copiously inside his coat and reset the cap on his head, not one of the countless woolen ones knitted for him by Hester but a baseball cap, a poor choice for such a cold morning. Dellarobia said nothing. She was tired of telling people to put on clothes. If her children and husband couldn’t figure out it was winter, the world would still turn.

The temperature must have dropped this morning in the early hours. Frost lay on the ground in patterns, a white powder so dry and fine it flew up in tiny storms of confetti-frost ahead of their boots as they walked. They followed the path of the creek up the left side of the pasture, wordlessly agreeing to climb to the top and work their way across and down. The dusting of frost outlined a zone of temperature differential along both sides of the creek where the water had held in warmth overnight. She thought the words thermal mass, picturing the solid pelt of butterflies clinging to the great columnar trunks of the firs, which Ovid had described as giant water bottles. Watercress she had never noticed grew up through the surface of this creek, frozen to blackness in the air above but still green underwater, and also alive in a narrow zone an inch above the surface of the moving creek. She had heard him say the word thermocline, and now she could see that too. She had begrudged the clubbish vocabulary at first, but realized now she had crossed some unexpected divide. Words were just words, describing things a person could see. Even if most did not. Maybe they had to know a thing first, to see it.