'I shouldn't say that again if I were you,' said the Djinn; you might say it once too often. Bubbles, I want you to work.'
And the Camel said 'Humph!' again; but no sooner had he said it than he saw his back, that he was so proud of, puffing up and puffing up into a great big lolloping humph.
'Do you see that?' said the Djinn. 'That's your very own humph that you've brought upon your very own self by not working. To-day is Thursday, and you've done no work since Monday, when the work began. Now you are going to work.'
Rudyard Kipling from Just So Stories