the roman army required officers in charge of catapults to have a good musical ear

so they could assess the tensions of the ropes by ear

Source: Structures: Or Why Things Don't Fall Down by J.e. Gordon
added 2012-04-10T16:33:58Z by anders

necking

form of fracture where material deforms plastically before breaking in tension

Source: Structures: Or Why Things Don't Fall Down by J.e. Gordon
added 2012-04-10T16:33:58Z by anders

trees grow pre-stressed

the outside wood is tensioned to 4,000 psi while the inner wood is compressed

Source: Structures: Or Why Things Don't Fall Down by J.e. Gordon
added 2012-04-10T16:33:58Z by anders