But he thought he had caught me laughing, and it increased his irritation.

Of course I knew he thought I was laughing privately--for I was experienced; they all think that, and it has a good effect; it sharpens their annoyance and debilitates their play.
He made another trial and failed.

Once more he was astonished; once more he was humiliated--and as for his anger, it rose to summer-heat.

He arranged the balls again, grouping them carefully, and said he would win this time, or die.

When a client reaches this condition, it is a good time to damage his nerve further, and this can always be done by saying some little mocking thing or other that has the outside appearance of a friendly remark--so I employed this art.