Discharge lines on vessel. TZWA.
T Tropical seawater line.
Z summer seawater line (the line also passes through the centre of the circle).
W winter seawater line
WNA winter seawater line for the North Atlantic. Located just below W.
TZW tropical freshwater line
SW summer fresh water line
The distance between Z and ZW is the additional sinking that the ship gets in the lighter freshwater. On a river it is therefore usually possible to load up to this SW mark, as the ship rises to the summer mark once it has left the river mouth.
In de donkere kamer van mijn vader stond ik als klein ventje, gehuld in geheimzinnig rood licht, de geur van ontwikkelaar op te snuiven. Dat heeft me betoverd. .. Read more…