In front of the club was strung out a long line of cars, and at the dock several speed boats of national and international reputation, among them the famous Streamline II, at our instant beck and call.  In it Craig had already placed some rather bulky pieces of apparatus, as well as a brass case containing a second triple mirror like that which he had left with Armand.

With McNeill, I walked back along the pier, leaving Kennedy with Armand, until we came to the wide porch, where we joined the wallflowers and the rocking-chair fleet.  Mrs. Verplanck, I observed, was a beautiful dancer.  I picked her out in the throng immediately, dancing with Carter.

McNeill tugged at my sleeve.  Without a word I saw what he meant me to see.  Verplanck and Mrs. Hollingsworth were dancing together.  Just then, across the porch I caught sight of Kennedy at one of the wide windows.  He was trying to attract Verplanck’s attention, and as he did so I worked my way through the throng of chatting couples leaving the floor until I reached him.  Verplanck, oblivious, finished the dance; then, seeming to recollect that he had something to attend to, caught sight of us, and ran off during the intermission from the gay crowd to which he resigned Mrs. Hollingsworth.

“What is it?” he asked.

“There’s that light down the bay,” whispered Kennedy.

Instantly Verplanck forgot about the dance.

“Where?” he asked.

“In the same place.”

I had not noticed, but Mrs. Verplanck, woman-like, had been able to watch several things at once.  She had seen us and had joined us.

“Would you like to run down there in the Streamline?” he asked.  “It will only take a few minutes.”

“Very much.”

“What is it—­that light again?” she asked, as she joined us in walking down the dock.

“Yes,” answered her husband, pausing to look for a moment at the stuff Kennedy had left with Armand.  Mrs. Verplanck leaned over the Streamline, turned as she saw me, and said:  “I wish I could go with you.  But evening dress is not the thing for a shivery night in a speed boat.  I think I know as much about it as Mr. Verplanck.  Are you going to leave Armand?”

“Yes,” replied Kennedy, taking his place beside Verplanck, who was seated at the steering wheel.  “Walter and McNeill, if you two will sit back there, we’re ready.  All right.”

Armand had cast us off and Mrs. Verplanck waved from the end of the float as the Streamline quickly shot out into the night, a buzzing, throbbing shape of mahogany and brass, with her exhausts sticking out like funnels and booming like a pipe organ.  It took her only seconds to eat into the miles.

“A little more to port,” said Kennedy, as Verplanck swung her around.

Just then the steady droning of the engine seemed a bit less rhythmical.  Verplanck throttled her down, but it had no effect.  He shut her off.  Something was wrong.  As he crawled out into the space forward of us where the engine was, it seemed as if the Streamline had broken down suddenly and completely.