Assertion: snorkel's feature | /r/CapableOf | comprise the use of an air trap
Facets:
value: to make
type: PURPOSE
Source sentences:
text: Still another feature of the present invention comprises the use of an air trap on the ambient water side of the purge valve to make it easier for water to drain through the purge valve than would otherwise be the case if the water were draining through the purge valve against the higher viscosity of the ambient water.