Assertion: horse chestnut | /r/ObjectUse | used as a source of starch
Facets:
value: during the two world wars
type: TEMPORAL
Source sentences:
text: During the two world wars, horse-chestnuts were used as a source of starch which in turn could be used via the Clostridium acetobutylicum fermentation method devised by Chaim Weizmann to produce acetone.