Assertion: aircraft's propeller | /r/CapableOf | double boat's previous speed
Facets:
value: from about four miles
type: OTHER
value: to smith's surprise
type: MANNER
Source sentences:
text: By a fortuitous accident, the wooden propeller of two turns was damaged during a voyage in February 1837, and to Smith's surprise the broken propeller, which now consisted of only a single turn, doubled the boat's previous speed, from about four miles an hour to eight.