Assertion: crampon | /r/CapableOf | prove its efficacy
Facets:
value: in 1938
type: TEMPORAL
Source sentences:
text: The 12-point crampon proved its efficacy in 1938 when, on the first ascent of the Eigernordwand, German climbers Anderl Heckmair and Ludwig Vörg — wearing 12-point crampons — overtook a pair of Austrian climbers wearing nailed boots and 10-point crampons, respectively.