One morning, a few days later, as we were rising from breakfast, Thorwald said:
“Well, my friends, I suppose you will go to church with us to-day?”
“To church?” asked we in one breath.
“Yes, this is Sunday.”
“Oh, is it?” I said. “I began to think you didn’t have Sunday here. It is now eight days since our return from the moon, and this is the first we have heard of it.”
“Let me see,” said Thorwald, “I believe this is the first Sunday we have spent at home since you came to us.”
“Then how long is your week?”
“Ten days.”
“That accounts for our misunderstanding,” I said, “for our Sunday comes every seventh day.”
“That is an odd number,” returned Thorwald. “With us the week is the basis of our decimal method of reckoning. We have one hundred minutes in an hour and ten hours in a day.”