When moisture ceases to bridge the contacts, the relay opens, and the lid-closing circuit is completed. ... to retain about VAp mcn of water at all times, so that the glass membrane of a nonrefillable combination electrode is kept moist. ... The sensing portion of a pH electrode, an automatic temperature-control probe, and the outlet from the constant-head reservoir ... manual operation of the collector, a manual opening-closing control switch, and lid-opening and lid-closing indicator lights.
|Title||:||A precipitation collector and automated pH-monitoring system|
|Author||:||Gerald M. Aubertin, Benjamin C. Thorner, John Campbell, Northeastern Forest Experiment Station (Radnor, Pa.)|