Devices providing means for diminishing the resistance between the water and the vessel when moving through the water and effective in increasing the speed. The present types comprise friction-roller surfaces, conveyers, and air-distributing means or attachments to produce a better cutting edge.
SEE OR SEARCH THIS CLASS, SUBCLASS:
232, and 233, for devices for distributing oils or liquids between the ship's skin and the water.
SEE OR SEARCH CLASS
440, Marine Propulsion,
38+, and indented subclasses for vessels having means to expel air or water about the surface of the submerged hull with sufficient effect and force to propel the vessel.
