Page 85 of The Luckiest Lady in London

If he ever noticed her lust simmering underneath her scholarly attention, he did not remark upon it. And did not let it impair his effectiveness as an instructor.

“As you can see, the relative thinness or fatness of an ellipse is determined by the ratio of distance from focus to distance from directrix, or eccentricity, represented by the Greek letter epsilon.”

She held her breath as a remarkably symmetrical oval appeared on the blackboard, complete with two foci and two directrixes.

“The very nature of the ellipse, the fact that it closes on itself, sets the value of its eccentricity between zero and one, for the foci are never points on the ellipse, and the distance from focus can never be greater than the distance from directrix. But watch what happens when e is equal to one.”

A parabola rose above the x-axis, its two arms perfect mirror images of each other. An unwanted heat began to pool inside her belly.

“Every point on the parabola is equidistant from the focus and the directrix. Now, when e exceeds one, however, a hyperbola results.”

An elegant x materialized, centered on the origin, its four arms extending into infinity. Despite her better intentions, she found herself breathing more rapidly.

“All three of these forms, along with the circle, can be formed by intersecting a plane through a solid cone, as Apollonius of Perga discovered centuries before Christ.”

A fire roared in the room. Afternoon sunlight streamed in from the windows. It was warm. Prodigiously warm. He unbuttoned his morning coat and proceeded to peel it off. Louisa stared.

“Most of his books have been lost. But Conics, which survived, is still considered one of the greatest scientific works of the ancient world and…”

It had been weeks since she last saw his naked form, the moisture on his skin gleaming in firelight. She wanted to run her hands over him as he whispered the impassioned corollaries of non-Euclidean geometry. Perhaps he would push her onto his desk, sweeping aside all his notebooks as he did so. And she would plunge her hands into his hair—

“Lady Wrenworth,” someone called her, seemingly from the bowels of the manor.

She made no reply. The staff could get by on their own for another half hour.

“Lady Wrenworth!” the voice snapped, along with an explosive noise that almost made her jump out of her chair.

He had slammed a yardstick against the corner of her desk. Her heart thumped with the unexpected ferocity of it.

“Yes?” she squeaked.

He slid the yardstick across the palm of his left hand, a rather malevolent gesture.

“My dear,” he said calmly, “I spend hours every day preparing for these lectures. I have a right to expect respectful attention.”

She swallowed. “I apologize. It won’t happen again.”

He was unappeased. “I doubt that. It isn’t the first time I’ve caught you at it. It isn’t even the first time today.”

Her cheeks scalded. She hung her head.

He sighed softly. “Perhaps I should dismiss class early today, since you cannot seem to concentrate.”

Her gaze flew up. “No, no, please don’t.”

“Then what should I do?”

His voice was most reasonable, yet her knees quaked. Her heart quaked, too, violently. She was the one who had once boasted to him of her ability to endure the deprivation of what she truly wanted. If that were still the case, then she should be able to modulate her voice to something that mimicked his appropriateness, and tell him to continue with the lesson, from the point where the value of the eccentricity exceeded one.

“You should punish me as you see fit, my lord,” she heard herself say, half in dismay, half in…anxiety, as if afraid he wouldn’t.

He leaned against the edge of his desk and crossed his arms before his chest. “When I misbehaved as a child, my tutor would send me to that blackboard”—he indicated the bigger blackboard on the wall—“and make me stand facing it, while he read a magazine.”

She pulled her lips and did as she was told. She supposed some part of her must have hoped that he would tell her to bend over his desk, as they’d laughingly discussed during a different age of the world altogether.

The blackboard was full of ellipses, parabolas, and luscious hyperbolas. She felt as lonely as she ever did in this marriage, standing with her nose almost touching the chalk marks, while the clock on the mantel ticked second by second.

Without being conscious of it, she counted the seconds—fifty-two, fifty-three, fifty-four, fifty-five—as if that would give structure and meaning to an otherwise blank, miserable stretch of time.