Assertion: gatling gun's use | /r/HasProperty | its initial test
Facets:
value: on 3 may
type: TEMPORAL
value: in battle
type: LOCATION
Source sentences:
text: The most effective official use was its initial test in battle when on 3 May 1862, at the battle of the Seven Pines, Va., under the direction of the inventor, a battery of the weapons opened fire on the Union forces with telling effect.