Dredges

A dredge of the type having a hull on which are mounted a first spud and a second spud each vertically slidable and adapted to be driven down into a sea bed to anchor the hull, wherein:

• said first spud is vertically slidable through a spud frame on a carriage mounted on said hull and adapted to be slidably moved longitudinally relative to said hull,
• said second spud is vertically slidable through a spud frame on a carrier fixed on said hull,
• for each said spud there is an associated lifting means for raising said associated spud, an associated locking means for holding said associated spud in raised position, and an associated release means for releasing said associated locking means to permit said associated spud to drop and drive into the sea bed, wherein said lifting means and said locking means comprise an apertured lifting plate disposed above an aperture locking plate, each of said plates being fitted closely about said associated spud and adapted to permit free passage of said associated spud therethrough when substantially perpendicular to said associated spud but to hold said associated spud frictionally when tilted, said locking plate being fulcrumed at one side on a fulcrum on said spud frame of said associated spud so as to tilt gravitationally and to lock said associated spud against descent while permitting said associated spud to be lifted by said lifting plate, said lifting means also including means for raising and lowering said lifting plate and tilting it when raising it to cause said lifting plate to grip and lift said associated spud, and
• propelling means are provided for advancing said hull relative to said spud carriage when, said second spud being raised, said first spud is driven into the sea bed.