Cool Boat: The first wave of bobbies sent against the Steam Castle cross the Thames on copies of the Turbinia (which showed up almost 30 years early).
Nevertheless, the machines used by the British Army are easily 50 years ahead of their time, and even the locomotives that he employs to stop the Steam Castle are beyond what would have been considered state-of-the-art at the time. Boring, but Practical: Robert Stephenson's inventions aren't nearly as outrageously advanced as those developed by the Steam family or used by the O'Hara Foundation.The submersible marines showcased this with one actually slipping on the steps getting out of the water, unceremoniously bonking his faceplate on each one as he fell back into the water. But really, pretty much any invention that the O'Hara Foundation was "showcasing" at the Exhibition.Awesome, but Impractical: The Aero Corps.
Their primary designer even says (in 1866) "Shoot me and you'll set science back fifty years.