The tube.
Ink Repalcements
vountain pen
The thing that you can buy for your pen is an Ink Cartridge. And the thing that makes your pen work is an Ink Cartridge
ink cartrages from rymans or whsmith
Cartridges
cart
an ink cartridge you get them from stationers :L
yu use a cartridge
cartridge
Cartridges
When the piston of a fountain pen is dipped into ink and released by pressing, it creates a vacuum that draws ink into the pen through the nib. This is due to the pressure difference between the inside of the pen (lower pressure) and the outside (atmospheric pressure), causing the ink to flow in to equalize the pressure.
an ink cartridge, which has the advantage of keeping the flow of ink steady and prevent smudging of ink on the hands and paper and making the palm dirty with smudges of ink which cannot be washed away completely if the ink is waterproof !