They might be used in time in place of horse-drawn busses and ice wagons and drays.
Wilbur was chilled by this prediction.

He had more than half meant to drive horses to one of these useful affairs, but what if they were to be run by machinery?
Linotypes to spoil typesetting by hand, and now horseless carriages to stop driving horses! He wondered if it would be any use to learn any trade.

He would have liked to ask Sharon, but hardly dared.
"Well, it's an age of progress," said Sharon at last.

"We got to expect changes." Wilbur was at home on this topic.

He became what Winona would have called informative.
"We can't stop change," he said in his father's manner.