Writing instrument

In a writing instrument comprising a cylindrical casing having a rear end and a forward end axially spaced apart from each other, an ink reservoir in said casing, and a writing nib having its rear end in said ink reservoir and its forward end projecting from the forward end of said casing, said nib having a rounded tip portion extending forwardly from said forward end of the casing and having an inner capillary conduit which extends axially through the nib;

• the improvement wherein said inner capillary conduit forms, in a transverse cross section of the nib, at least one straight slit which extends from the center of the cross section toward the outer periphery of the nib in the substantially radial direction of the cross section, and forms a plurality of radially spaced apart arc shaped slits which are coaxial with each other about said center, a part of each of said arc shaped slits interconnecting with said straight slit, said radially spaced apart arc shaped slits being opened to a rounded outer surface of the tip portion.