  We have carried out a multi-species study of a region which has had previous
measurements of strong magnetic fields through the CN Zeeman effect in order to
to explore the relationship between CN and N$_2$H$^+$, both of which have
evidence that they remain in the gas phase at densities of 10$^5$ - 10$^6$
cm$^{-3}$. To achieve this we map the 1 arcmin$^2$ region around the UCHII
region of W3(OH) using the Combined Array for Millimeter-wave Astronomy
(CARMA). Approximately 105 hours of data were collected in multiple array
configurations to produce maps with an effective resolution of $\sim$
2.5\arcsec at high signal-to-noise in CN, C$^{18}$O, HCN, HCO$^+$, N$_2$H$^+$,
and two continuum bands (91.2 GHz and 112 GHz). These data allow us to compare
tracer molecules associated with both low and high density regions to infer gas
properties. We determine that CARMA resolves out approximately 35% of the CN
emission around W3(OH) when compared with spectra obtained from the IRAM-30
meter telescope. The presence of strong absorption lines towards the continuum
source in three of the molecular transitions infers the presence of a cold,
dark, optically thick region in front of the continuum source. In addition, the
presence of high-velocity emission lines near the continuum source shows the
presence of hot clumpy emission behind the continuum source. These data
determine that future high-resolution interferometric CN Zeeman measurements
which cannot currently be performed (due to technical limitations of current
telescopes) are feasible. We confirm that CN is indeed a good tracer for high
density regions; with certain objects such as W3(OH) it appears to be a more
accurate tracer than N$_2$H$^+$.
