It was too late to start off now:

"I'm waiting, too. Suppose I get in and take a turn around the park
with you? You've never invited me to try your new car."

Cora was surprised. She knew very well she had not asked him to
ride in the Whirlwind, and she had no intention of doing so. She was
about to reply, when Sid jumped in beside her.

"I see you're not going to ask me," he went on, "and, as I have no
idea of losing the chance for a spin, I'll get in without an
invitation."

With a quick motion he shoved over the spark lever and the motor
started, for a charge had remained in one of the cylinders,
obviating the necessity of cranking up.

"There, we're all ready to go," he said.

Cora was dumfounded. But she felt it would not do to make a
vigorous protest in such a public place. For a moment her feelings
threatened to master her. Then she regained control of herself,
threw in the clutch and turned the car in the direction of the park.
After all, it might be better to humor Sid.

"So you brought Paul Hastings over?" drawled the youth.

Then he had seen her, after all. Cora's precautions were useless.