Refuelling at sea.
Most yachts carry spare fuel in containers.
If you ever try to refuel from a container at sea you will find that the diesel blows everywhere and the slightest motion of the boat can cause a major spillage.
The only solution I have found that works easily is to carry a syphon of the type use to make beer or wine.
You will find that the fuel can be easily transferred without any spillage, it also means you do not have to try starting the syphon by sucking the fuel through a tube.
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