This larger of the two Edson Classic Series of steering pedestals is ideal for sailboats over 29 ft (8.8 m), and is available with traditional chain and wire drive or in CD-i geared versions.
These are the chain and wire rope versions.

Extra large 8" pedestal top fits larger compasses up to 6" card size
Accepts all styles of Edson wheels
Pedestal top is pre-drilled for mounting compass, pedestal guard plate, or engine controls
Stainless steel wheel shaft and sprocket
Triple races of stainless steel needle bearings and stainless bearing liners
Convenient thru-hub wheel brake with stainless knob is included
Durable glossy white baked-on urethane finish
All non-magnetic construction
Hex head recesses in base make for easy one-person installation
Suitable for use with windvane self-steerers
Replaces Edson's #400 and #401 pedestals
This pedestal can be fit with any of three styles of pedestal guard - straight, angled, and offset (all sold separately).
A large selection of other accessories is also available, such as instrument housings, drink holders, tables, etc.

Heavy on the technical side...
Classic Series pedestals incorporate a time-proven, reliable, chain and wire steering mechanism which has been used on thousands of boats for over 80 years.
Chain and wire systems are readily adaptable to most vessels.
They are very strong, adjustable, easily maintained, and constructed with parts that can be readily sourced, worldwide.

In a typical system, the steering wheel is mounted on a shaft which has a toothed sprocket on it.
A section of chain is draped over the sprocket, and the ends of the chain are connected to lengths of wire cable within the column of the pedestal.
The wire cables are led, via pulleys, from the bottom of the pedestal to a steering quadrant or radial drive wheel which is attached to the top of the rudder post.
Turning the steering wheel turns the sprocket which moves the chain/wire cables which, in turn, rotate the quadrant/radial drive, thus turning the rudder.

The art in the system is aligning the sheaves and routing the wire cables from the bottom of the pedestal, through the boat to the rudder, so they travel as directly as possible, yet do not impinge on usable internal space.