Welcome to the tradition of fine writing!
These dipping pens will write for two or three lines with just one dip into the inkwell. It feels very much like writing with a pencil and the line has a constant width on the page, regardless of how hard you press on it. Although you can make some beautiful lines and sketches, don't mistake these pens with other pens that produce variable-width lines such as calligraphy pens.
Glass pens are suitable for journaling, writing long letters and sketching
(artwork) because they don't require as many dips in the inkwell. The nibs are
easy to clean and you will enjoy using different colors of ink to express
yourself.
Because the ink most commonly used with these pens is the water base fountain pen thickness, it is sufficient to rinse the nib out a couple of seconds in a glass of water (or until the pigment no longer shows up in the water) then wipe out the excess water.