Moist stared disconsolately at a letter from a Ms Estressa Partleigh of the Campaign for Equal Heights. The Post Office, apparently, was not employing enough dwarfs. Moist had pointed out, very reasonably, he thought, that one in three of the staff were dwarfs. She had replied that this was not the point. The point was that since dwarfs were on average two-thirds the height of humans, the Post Office, as a responsible authority, should employ one and a half dwarfs for every human employed.