Franklin was wolfing down his crayfish soup with gusto—with seeming disregard for whether the month was spelled with an R or not—also disregarding his painful gout and kidney stones, which he referred to as his “Grit and Gravel.”

“Your first and second questions both have the same reply,” Franklin said, setting his spoon aside from his empty bowl. “I knew it was encrypted, and I know what it means because I have the key!”

There was much commotion, which afforded Mme Helvetius the opportunity to give Franklin a healthy poke in the ribs. As he leaned to peck her cheek, he whispered, “Say nothing at all—the game has just begun.” She lapsed into silence.

“Today is a Tuesday,” Franklin said. “As many of you know, Mme Helvetius, who sits by my side, for decades held philosophical salons on that day with her husband in their Paris mansion. You may also know that Madame is the founding sponsor of an elite lodge of Freemasons, here in France, known as the Loge des Neuf Soeurs. This club, of which I am an initiate and twice a grandmaster, also meets on Tuesdays, and continues to perform many useful services for our United States. What significance can we assign to this day of the week?”

“It’s the day of the Norse god, Tiw, which is Mars in French,” said Quincy.

“Indeed,” agreed Franklin. “But there is something more.”

The servants had arrived to remove and replace the plates. When they had passed the platters of duckling, truffled foie gras, quail, rabbit and legumes, they topped off the wineglasses and departed. Only then did Franklin take the floor.

“I once attended the meeting of another such club, in another time and place,” Franklin began. “It was nearly thirty years ago, in 1754, that I had reason to leave my home in Philadelphia and travel to points south. At that time, there was no inkling that one day—a day not far in our future—we colonists would revolt against the mother country and form a new republic. Indeed, at the moment we were having more trouble with the French, who were fortifying the Ohio River Valley. And with the Indians, whom they were also fortifying, with French weapons and Louisiana rum.

“In a few years, a young soldier named Washington would fire the first shot in the French and Indian War. As that war soon dragged all of Europe, even India, into a Seven Years War leading to our own revolution, it would truly become the first ‘shot heard round the world.’

“In January of that year, I’d just attended a summit of some of these disgruntled Indian nations—only to learn, on my return to Philadelphia, that I’d been appointed deputy postmaster for the colonies, an important role. As there was another Indian conference looming in a few months, at Albany, I determined it would be a prudent time right now for me to make a quick tour of postal facilities throughout the southern colonies. Among the most important of these was Annapolis, on the Chesapeake Bay.