An old “forecaster” is this Spanish monk:
http://www.surnames.org/aladin/frare.html
It is made with intestine fiber that reacts to humidity and (it is said) to pressure variations.
This monk in original version is rather inaccurate and unusable, but I did modify and adapt the Zambretti algorithm, plus some other data such as temperature, humidity and the boltek sensor, and made it work this way - sorry it is in Catalan:
http://frater.casacota.cat