In this photo of Chicago’s Madison Street, c. 1910, you can see a few varieties of horsepower …

There are several automobiles (all parked along the curbs), an electric streetcar, and quite a few horse-drawn vehicles: parked, being driven, and one, a delivery wagon, being either unloaded or loaded. There’s even a vehicle that looks almost exactly like a horse-drawn delivery van, except that I can’t see a corresponding horse … so it must have a motor somewhere.

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