Editing Paddle steamer (section)

== Paddle wheels ==
[[File:paddle wheel small.jpg|frame|right|Left: [[Rivet]]ed steel [[paddle wheel]] from a sidewheeler paddle steamer on the lake of Lucerne<br />Right: Detail of a steamer]]
The paddle wheel is a large steel framework wheel. The outer edge of the wheel is fitted with numerous, regularly spaced paddle blades (called floats or buckets). The bottom quarter or so of the wheel travels under water. An engine rotates the paddle wheel in the water to produce [[thrust]], forward or backward as required. More advanced paddle-wheel designs feature "feathering" methods that keep each paddle blade closer to vertical while in the water to increase efficiency. The upper part of a paddle wheel is normally enclosed in a paddlebox to minimise splashing.