efflorescence of the desert throws the air over them into such a state
of quivering undulation as produces the most wonderful and varying
effects, distorting the forms of objects, and rendering the most
familiar strange and hard to be recognized. A mud bank furrowed by the
rain will exhibit the appearance of a magnificent city, with columns,
domes, minarets, and pyramids; a few stunted bushes will be transformed
into a forest of stately trees; a distant mountain will, in the space of
a minute, assume first the appearance of a lofty peak, then swell out at
the top, and resemble a mighty mushroom, next split into several parts,
and finally settle down into a flat tableland. Occasionally, though not
very often that semblance of water is produced which Europeans are are
apt to suppose the usual effect of mirage. The images of objects are
reflected at their base in an inverted position; the desert seems
converted into a vast lake; and the thirsty traveller, advancing towards
it, finds himself the victim of an illusion, which is none the less
successful because he has been a thousand times forewarned of its
deceptive power.

In the mountain range or Zagros and the tracts adjacent to it, the
climate, owing to the great differences of elevation, is more varied
than in the other parts of the ancient Media. Severe cold prevails in
the higher mountain regions for seven months out of the twelve, while
during the remaining five the heat is never more than moderate. In
the low valleys, on the contrary, and in other favored situations, the
winters are often milder than on the plateau; while in the summers, if
the heat is not greater, at any rate it is more oppressive. Owing to the
abundance of the streams and proximity of the melting snows, the air is
moist; and the damp heat, which stagnates in the valleys, broods fever
and ague. Between these extremes of climate and elevation, every variety
is to be found; and, except in winter, a few hours' journey will almost