  Context: We investigate mid-infrared and X-ray properties of the dusty torus
invoked in the unification scenario for active galactic nuclei.
  Aims: We use the relation between mid IR and hard X-ray luminosities to
constrain the geometry and physical state of the dusty torus.
  Methods: We present new VISIR observations of 17 nearby AGN and combine these
with our earlier VISIR sample of 8 Seyfert galaxies. Combining these
observations with X-ray data from the literature we study the correlation
between their mid IR and hard X-ray luminosities.
  Results: A statistically highly significant correlation between the rest
frame 12.3 mircon (L_MIR) and 2-10 keV (L_X) luminosities is found.
Furthermore, with a probability of 97%, we find that Sy 1 and Sy 2 have the
same distribution of L_MIR over L_X.
  Conclusions: The high resolution of our MIR imaging allows us to exclude any
significant non-torus contribution to the AGN mid IR continuum,thereby implying
that the similarity in the L_MIR / L_X ratio between Sy 1s and Sy 2s is
intrinsic to AGN. We argue that this is best explained by clumpy torus models.
The slope of the correlation is in good agreement with the expectations from
the unified scenario and indicates little to no change of the torus geometry
with luminosity. In addition, we demonstrate that the high angular resolution
is crucial for AGN studies in the IR regime.
