Sir Joseph went on with his story:

"We were some ten or a dozen miles off the mouth of the Mersey--"

"Nautical miles, Joseph."

"It doesn't matter, Lavinia."

"Excuse me, brother, the late great and good Doctor Johnson said
accuracy ought always to be studied even in the most trifling things."

"They were common miles, Lavinia."

"They were nautical miles, Joseph."

"Let us waive the point. Mahogany Dobbs and I happened to be below in
the cabin, occupied--"

Here Sir Joseph paused (with his amiable smile) to consult his
memory. Miss Lavinia waited (with _her_ amiable smile) for the coming
opportunity of setting her brother right. At the same moment Natalie
laid down her knife and softly touched Launce under the table. When
she thus claimed his attention the six pieces of ham were arranged as
follows in her plate: Two pieces were placed opposite each other, and
four pieces were ranged perpendicularly under them. Launce looked, and
twice touched Natalie under the table. Interpreted by the Code agreed
on between the two, the signal in the plate meant, "I must see you in
private." And Launce's double touch answered, "After breakfast."

Sir Joseph proceeded with his story. Natalie took up her knife again.