Balloons are nifty, but they’re hard to steer, and conventional motor-driven propellers are too heavy. So in 1887, Frenchman Charles Wulff proposed tying eagles to the car to form living propellers.

The birds would wear shoulder straps to keep them in place. The man in the car shouts his destination into a speaking tube, and the conductor uses a hand wheel and rollers to point the birds in the appropriate direction “quite independently of their own will.” A net can be lowered to stop them from flapping.

What could go wrong?