Translations:Pneumatic filler/2/en

The outer barrel of the pen had, as for the blow filler an aeration hole on the bottom. The filling was obtained by sliding back the body of the pen and then bringing it back into position by keeping the hole in the bottom closed with a finger. In this way the pressure generated on the sac causes its compression, but once left free the aeration hole the subsequent expansion of the sac causes the suction of the ink.