He stood up straight and looked the world squarely in the fields and hills. To add weight to his words he stuck the rabbit bone in his hair. He spread his arm out wide. "I will go mad!" he annouced.

This must be Thursday. I never could get the hang of Thursdays

Zaphod felt he was teetering on the edge of madness and wondered if he shouldn't just jump over and have done with it.

Arthur felt happy. He was terribly pleased that the day was for once working out so much according to plan. Only twenty minutes ago he had decided he would go mad, and now here he was already chasing a Chesterfield sofa across the fields of prehistoric Earth.