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New York, 1917. "Dorothy Klewer." ("The noted California beauty who is the rage of New York," in case you were wondering.) Bain News Service. View full size.
Looking closer at the photo it appears that the studded tires are skins with studs fitted over the smooth pneumatic rim mounted tires.... Almost like a hand in glove!
I agree, battery powered electric motor. The box to right of driver appears to have cables in conduit coming out the bottom: probably the battery. Are those terminals for the charger? (You wouldn't want to run a gasoline engine indoors due to exhaust and noise.)
Tires: two studded in the back for drive, one studded in front to enable steering, one smooth in front. Because studded tires cost far more and one is sufficient to steer?
Least essential equipment: the horn - how fast could this thing go?
If it's not a Zamboni, it's only an ice resurfacer.
I agree it looks electric. Note the electric conduit under the black box.
probably afraid she'll put it in reverse instead of forward.
Honk the horn and try and push the clutch down with your skates on.
Most likely an electrically powered tow motor, I see no radiator!
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