I stretched myself on the straw, without much desire to continue conversation. He seemed to be searching in his pocket. I saw a sort of metallic tube between his fingers, which he unscrewed; then holding the thing out to me, said:

"Here you are, just look at this will you?"

He explained:

"It's a mouth thermometer. I always carry it on me."

"What an idea!"

I did not know that the instrument existed in this form. The graduated glass tube only measured a few centimetres. I mechanically turned it round and round until I saw the little column of mercury shining.

"102.2°!" I exclaimed. "Is that your temperature?"

"Yes."

"You ought to take some ... quinine."

He shook his head.