194 / | HD | CHECK-ACTUATED CONTROL MECHANISMS |
302 | DF | INCLUDING MEANS TO TEST VALIDITY OF CHECK {4} |
303 | DF | .~ By testing material composition {4} |
304 | DF | .~.~ Having electric circuit completed by check {7} |
316 | .~.~.~ Circuit includes elongated contact (e.g., long slide, etc.) |