The search for ever better methods for transporting heavy unit loads by sea has also led to the development of dock ships onto which pontoons are floated on and off.
Uphando ngendlela ezingcono zokuhambisa iiyunithi ezinzima ikhokelela kwinkqubela phambili yedokisi lweenqanawa apho imiphantsi yeenqanawa ethe tyaba ejika jikayo phezulu naphantsi