Moving the accommodation and engine room aft was a sensible option when ships relied on mechanical drive to the propeller but it does have its drawbacks. On a container vessel for example the height of the deck cargo is restricted because of sight limitations from the bridge. On all vessels there is more vertical movement at the ends of the ship making living there less comfortable than amidships where movement is much smaller. Today, electric drive is becoming more common and actively promoted. The ships engines (there will be more of them but smaller) can be located at any point onboard and will generate electricity which can be fed to motors in podded propellers outside the ship using cables that can run between frames. The added advantage of this configuration is that a ship is not disabled if one engine breaks down or the ships structure is damaged as in a collision or grounding. Multi-purpose vessels operating in the deep-sea markets tend to be fairly small by today’s standards, most being in the 10/25,000 deadweight size category. Those employed on scheduled routes are normally more sophisticated and sometimes are built to custom-serve that operation, being termed, perhaps, ‘cargo-liners‘, but such vessels are declining in numbers, line-operators frequently chartering-in conveniently placed and priced ‘tramp-vessels‘ from the international dry-cargo market; vessels which ply the oceans voyage by voyage, their owners/operators seeking cargoes in the vicinity of where their vessels happen to be available.