  We have used the Taeduk Radio Astronomy Observatory to observe the Orion A
and Ophiuchus clouds in the $J=$1$-$0 lines of $^{13}$CO, C$^{18}$O, HCN,
HCO$^+$, and N$_2$H$^+$ and the $J=$2$-$1 line of CS. The fully sampled maps
with uniform noise levels are used to create moment maps. The variations of the
line intensity and velocity dispersion with total column density, derived from
dust emission maps, are presented and compared to previous work. The CS line
traces dust column density over more than one order of magnitude, and the
N$_2$H$^+$ line best traces the highest column density regime
($\log(N_\mathrm{H_2}$) $>$ 22.8). Line luminosities, integrated over the
cloud, are compared to those seen in other galaxies. The HCO$^+$-to-HCN
luminosity ratio in the Orion A cloud is similar to that of starburst galaxies,
while that in the Ophiuchus cloud is in between those of active galactic nuclei
and starburst galaxies.
