Weather forecast > Wooden barometers
Wooden barometers have been making for centuries practically with no technologic shape changes. Diaphragm reacts to a change of pressure of surrounding air; it transfers to a dial pointer over leverage; then the hand shows the tendency of the air changes on the dial. When moving up – to the right, the weather is supposed to get better; on the other hand when pressure decreases it will probably rain. Due to mechanic transmissions only a small power is made and it doesn’t always have to be higher than mechanic friction. That’s why it’s sometimes necessary to tap on a glass on barometer so the tension loosens and the hand starts moving again – if the pressure change can be felt. The advantage of mechanic barometers is their operation without a dependence on electric current and their long effective life.
