Initially it was simply a cylinder of hard rubber suitably bevelled in the front part placed under the nib to leave space for writing, equipped on the upper part of the ''"[[channel]]"'' supply through which the ink arrives from the tank to the nib. The first variations occurred precisely in the construction of the channel, and in the addition of further grooves inside to facilitate the passage of the ink by capillarity. Through the same channel, even if later possible alternative paths have been foreseen, the air that replaces the ink that comes out of the pen tank flows. | Initially it was simply a cylinder of hard rubber suitably bevelled in the front part placed under the nib to leave space for writing, equipped on the upper part of the ''"[[channel]]"'' supply through which the ink arrives from the tank to the nib. The first variations occurred precisely in the construction of the channel, and in the addition of further grooves inside to facilitate the passage of the ink by capillarity. Through the same channel, even if later possible alternative paths have been foreseen, the air that replaces the ink that comes out of the pen tank flows. |