xanthin typhoid (Technical details are as follows: the leaf is wired in as one leg of the "bridge". The meter is wired across the bridge to detect voltage fluctuations. Some form of self-balancing bridge is best. If you want to get really technical you can use phase-locked chips and an alternating current input. This is far more sensitive than a DC bridge and has been used to build a "mind-powered" switch to open a garage door using a plant as the receiving medium). 000423 what's it to you? who go blather from