Assertion: sewing machine's motor | /r/AtLocation | machine
Facets:
value: in 1921
type: TEMPORAL
Source sentences:
text: Electric motors and bolt-on lights were introduced to the machines in 1921.
text: Electric motors and bolt-on lights were introduced to the machines in 1921, and the treadle tables gradually faded away to chunky box bottoms in the 1930s.