Sidewheeler

Sidewheel

The earliest steam vessels were powered by sidewheels, by far the dominant mode of marine steam propulsion, both for steamships and steamboats until the increasing adoption of screw propulsion from the 1850s. Though the sidewheels and enclosing sponsons make them wider than sternwheelers, sidewheelers may be more maneuverable, since some can move the paddles at different speeds, and even in opposite directions. This extra maneuverability makes sidewheelers popular on the narrower, winding rivers of the Murray–Darling system in Australia, where a number still operate.