Words: Mortise, n. and v.

HAL PORTER'S excellent memoir The Watcher on the Cast-Iron Balcony (1963) opens with the memory of two corpses seen 28 years apart and the reflection that "on or about the day King Edward VII died, these two corpses [were] young, agile and lustful enough to mortise themselves together to make me".

Mortise sounds more a matter of death than life, but is a Middle English term (from obscure French) for the cavity which receives a tenon to form a joint (as in a lock). Such an invisible device was used at something more enduring than Mr and Mrs Porter's union - Stonehenge - but as a metaphor Porter's inspiration was probably Othello (melting mountains ruin mortised oak) or Hamlet (subjects are mortised to the wheel of Majesty).