The primitives of temporal relations

An electric switch having a sealed casing or a closed type switch wherein a breather hose has its one end opened to the interior of a closed contact chamber, so that the breathing action of the contact chamber due to its temperature change is made through the breather hose. An opening at the other end of the breathing hose is located in an outside atmosphere of good condition, whereby air of high humidity is prevented from intruding into the contact chamber.