Complex systems are made easy to understand in this fascinating film about converting the air around us into work

This fascinating programme explains the basic principles that underpin pneumatic systems in everyday use and in manufacturing. Told in an entertaining manner by its presenter, Bill Thomas, the programme explains how air, in the form of wind, can and has been harnessed by sailing ships, windmills and, in a compressed form, by fairground organs. Using these examples as analogies, the presenter shows how the same principles that drive those machines find parallels in more complex systems and machinery. Relocating to a production line at the Lyons-Tetley coffee processing plant in Greenford, Middlesex, the programme shows a coffee packaging machine in operation. The presenter analyses each action of the machine and explains the mechanisms used to control the system. These include a large air-compressor, actuators and their pistons (analogous to a bicycle pump) valves and proximity switches. The machinery is shown operating at normal speed as well as in slow-motion - where the viewer can see each part of the machine working in a prescribed sequence - without the need for any computer-based control. The presenter relates how these systems, though complex in appearance, are in reality based on very simple and straightforward physical principles. Furthermore, this simplicity creates a clean, low-maintenance and efficient technology.