In fountain pens, this flow control is achieved thanks to the presence of the [[feeder]] channel, through which the ink can reach, due to the combined effect of gravity and capillarity, the height of the two wings of the [[nib]]. As long as the pen is not used, the surface tension prevents the ink from leaving the feeder and the nib, at least as long as they are correctly mounted and there is no other free passage than that of the feeder channel. | In fountain pens, this flow control is achieved thanks to the presence of the [[feeder]] channel, through which the ink can reach, due to the combined effect of gravity and capillarity, the height of the two wings of the [[nib]]. As long as the pen is not used, the surface tension prevents the ink from leaving the feeder and the nib, at least as long as they are correctly mounted and there is no other free passage than that of the feeder channel. |