The capillary is circular in cross section, this being obtained by drilling or {HEAD ~ extrusion} of {TAIL ~ a cylindrical bar} made of dielectric material 
of
The capillary is circular in cross section , this being obtained by drilling or { HEAD ~ extrusion } of { TAIL ~ a cylindrical bar } made of dielectric material
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH