Interstellar carbon abundance

We present 10 new measurements of carbon gas phase column density in the in terstellar medium. We have used spectra made with the Goddard High Resoluti on Spectrograph aboard the Hubble Space Telescope containing the CII 1334.5 Angstrom and CII* 1335.7 Angstrom lines. The continuum reconstruction meth od has been used to obtain the carbon column density from the Lorentzian da mped lines. Extinction curve parameters are determined in selected directions and relat ion between C/H ratio and extinction parameters is discussed. A correlation has been found between C/H and the strength of the 2175 Angstrom bump. Unl ike previous results, we notice that C/H changes with fractional abundance of molecular hydrogen, f(H-2). The average value of C/H = 3.55 . 10(-4) for lines of sight with f(H-2) < 1 . 10(-3) is the same as solar photospheric abundance from Grevese and Noels (1993) and may represent the real cosmic c arbon abundance.