  We consider the Harmonic crystal, a measure on $\mathbb{R}^{\mathbb{Z}^{d}}$
with Hamiltonian $H(\x)=\sum_{i,j}J_{i,j}(\x(i)-\x(j))^{2}+
h\sum_{i}(\x(i)-\dd(i))^{2}$, where $\x, \dd$ are configurations,
$\x(i),\dd(i)\in\mathbb{R}$, $i,j\in{\mathbb{Z}^{d}}$. The configuration $\dd$
is given and considered as observations. The `couplings' $J_{i,j}$ are finite
range. We use a version of the harness process to explicitly construct the
unique infinite volume measure at finite temperature and to find the unique
ground state configuration $\m$ corresponding to the Hamiltonian.
