P.W. Akkerman was founded in 1910 and in 2010, to celebrate the 100th Anniversary, they issued a line of inks and a very distinctive ink bottle.The ink bottle fills by tipping the bottle upside down so that ink flows from the large bottom section, into a small upper section. When you tip the bottle back up, a small marble rests in the neck of the bottle to divide the two sections. This is a method first developed circa 1935 by Jif-Waterman, the French subsidiary of Waterman at the time. Each of the colors are named for a location in The Hague.