When every one is starving with hunger, and dead tired, and soaked to the skin, Mackenzie fairly bubbles over with good-humour.

Dick.

When I'm in a bad temper, I much prefer every one else to be in a bad temper too.

Doctor.

These last few days, he's been positively hilarious. Yesterday he was cracking jokes with the natives.

Dick.

[Dryly.] Scotch jokes. I daresay they sound funny in an African dialect.

Doctor.

I've never seen him more cheerful. I said to myself: By the Lord Harry, the chief thinks we're in a devil of a bad way.

Dick.