And self-conscious. And a little light-headed.
He'd paid her a compliment, an unadulterated compliment, on something that genuinely mattered to her. She felt like a green debutante at her first ball after an unexpected dance with the most extraordinary, notorious rake of them all: She knew perfectly well that the fizzy warmth in her was unreciprocated, unwise, and uncalled for, but there wasn't a damned thing she could do about it.
He wrote in a quick, slanted hand, unraveling reams of equations that would look to the uninitiated as incomprehensible as the hieroglyphs before the discovery of the Rosetta Stone. Even she, having been extensively tutored in higher mathematics and mechanics—so that she wouldn't be hampered by ignorance when dealing with her own engineers—could understand only parts of it, looking at the numbers and symbols upside down.
She deciphered that he was working on something about the heating and exchanging of gases. When his calculations moved on to angular momentum, she further deduced that he was refining the design for an internal combustion engine.
She had her doubts about the automobile. Certainly it was wonderful and novel and—nowadays—feasible. But who other than the most adventurous and the most wealthy would want to own and operate one, when carriages were so much simpler and more convenient in town and trains a great deal faster and more reliable over long distances? At least one's horses were not likely to die three times going from London to Brighton.
But she was curious enough to have paid a visit to Herr Benz in Mannheim the previous summer and was about to negotiate a license to build Benz engines in her own factory. The internal abacus she'd inherited from her Rowland ancestors swiftly calculated the savings she'd realize if she could use Camden's design—if it worked.
And if he were truly her husband.
“What's the matter with your engine?”
“It can't expel exhaust gases fast enough when its rotational speed exceeds one hundred revolutions per minute,” he said, without looking up. Without expressing any surprise at her familiarity with subjects outside the grasp of the overwhelming majority of women— and men, for that matter.
But then, he knew all about the Honorable Mr. Williams, who'd been her tutor before he became her lover.
The partial vacuum created by the exodus of exhaust gas drew fresh air and fuel into the cylinder. The expanding gas created from the ignition of the air-and-fuel mixture powered the engine, but residual exhaust gases that were not expelled would reduce its efficiency.
“You should begin the expelling cycle at an earlier point in the crankshaft's rotation,” she said. “That would sacrifice a bit of power but improve your efficiency.”
“Correct.”
“The trouble comes in determining at which precise point, doesn't it?” she said. Her engineers had agonized over the voltage of the third rail they had designed for London's new underground tubes.
“Always,” he answered. “The design can be refined only to a certain point. I've narrowed it down to two possibilities and determined their angles to within one point two degrees. Now my engineers in New York will modify the engine and test it.”
“Good thing you won't get your hands dirty.”
“But getting my hands dirty is half the fun. I always build my own designs. I can build anything.” He glanced at her and smiled. Her heart thudded to a stop. The sun really did shine brighter when he smiled. “Would you like to be the first English lady to rumble down Rotten Row in a horseless carriage?”
She smiled despite herself. That fizzy warmth—half effervescent elation, half heedlessness—spread unabated within her. “I know you really can build anything. I know your little secret.”
He was puzzled. “Secret?”
“Claudia's gown that she wore to her first ball.”
“Ah that,” he said, relaxing. “That's not my secret so much as hers. She was rather mortified, if I remember correctly, that other people had ball gowns made by Monsieur Worth, while hers was cobbled together by her brother.”
“So modest.”
“When I say cobbled, I mean cobbled. I had no idea how to manufacture the kind of neckline she wanted without the bodice falling off her. So I took apart one of my mother's mesh bustles and wired the entire décolletage. She was terrified during the ball that the gown would either kill her or poke some handsome swain in the chest.”
“She showed it to me when she came to England in 1890,” said Gigi. “I couldn't believe that you made it until she swore it on the lives of all her children.”
“It was my first and last foray into haute couture,” he said dryly. “I was nineteen and thought there was nothing I couldn't do. When Claudia wept for hours on end because there was no room in the budget for a new gown for her first ball, I thought, how hard could it be? After all, couture was just the softer side of engineering, and I'd cut and sewn plenty of sails for my model ships.”