  We use new FUSE data to determine the column densities of interstellar DI,
NI, OI, FeII, and H2 along the HD41161 and HD53975 sightlines. Together with
N(HI) from the literature (derived from Copernicus and IUE data) we derive D/H,
N/H, and O/H ratios. These high column density sightlines have both log
H(HI)>21.00 and allow us to probe gas up to 1300 pc. In particular these
sightlines allow us to determine the gas phase D/H ratio in a hydrogen column
density range, log N(H)>20.70, where the only five measurements available in
the literature yield a weighted average of D/H = (0.86 +/- 0.08)E-5. We find
D/H=(2.14+ 0.51 - 0.43)E-5 along the HD41161 sightline. This ratio is 3sigma
higher than the weighted mean D/H ratio quoted above, for sightlines with log
N(H)>20.70, while the D/H ratio for the HD53975 line of sight, D/H = (1.02
+0.23 -0.20)E-5, agrees within the 1sigma uncertainties. Our D/H measurement
along the HD 41161 sightline presents the first evidence of variations of D/H
at high N(H). Our result seems to indicate that either the long sightlines that
according to the deuterium depletion model are dominated by cold undisturbed
gas where deuterium would be depleted onto carbonaceous grains occur at higher
N(H) than previously thought or that the clumping of low D/H values in the
literature for the long sightlines has another explanation. In addition, the
relatively high signal-to-noise ratio of the HD41161 data allows us to place
constraints on the f-values of some neutral chlorine transitions, present in
the FUSE bandpass, for which only theoretical values are available.
