Nobody would be brave enough to shout at you CED.
You are correct it is a simple steam engine dating from 1865. These little paddlers needed an extremely powerful, for the time, engine to cope with the service conditions. The solution was an adaptation of the basic steam engine designed by George Stephenson to power his ROCKET locomotive. The engine had a propulsive force comprising a twin cylinder single acting steam engine, each cylinder having a diameter of 35 inches with a stroke or piston travel of 42 inches. This simple arrangement provided a power output of 70 HP driving twin paddle wheels at each side of the vessel. Hopefully this has been of some help.