A turn of the propellor

There was an industrialist whose production genealogy inexplicably breaks strike, costing him zillions per day. He eventually tracks land an skilful who takes out a screwdriver, turns one propellor, and then - as the works cranks place to life - presents a bill for £10,000.

Affronted, the works owner demands an itemised writing. The good is prosperous to cause: "For turn a propeller: £1. For knowing which propellor to lose: £9,999."