little
below the thirty-fourth parallel, its southerly direction, it is brought
about Baghdad within twenty miles of the sister stream. From this point
there is again a divergence. The course of the Euphrates, which from
Hit to the mounds of Mohammed (long. 44 deg.) had been E.S.E., becomes
much more southerly, while that of the Tigris--which, as we have seen,
was for awhile due south--becomes once more only slightly south of east,
till near Serut, where the distance between the rivers has increased
from twenty to a hundred miles. After passing respectively Serut and El
Khitr, the two streams converge rapidly. The flow of the Euphrates is
at first E. S. E., and then a little north of east to Kurnah, while that
of the Tigris is S.S.E. to the same point. The lines of the streams in
this last portion of their course, together with that which may be drawn
across from stream to stream, form nearly an equilateral triangle, the
distance being respectively 104, 110, and 115 miles. So rapid is the
final convergence of the two great rivers.

The Tigris and Euphrates are both streams of the first order. The
estimated length of the former, including main windings, is 1146 miles;
that of the latter is 1780 miles. Like most rivers that have their
sources in high mountain regions, they are strong from the first, and,
receiving in their early course a vast number of important tributaries,
become broad and deep streams before they issue upon the plains. The
Euphrates is navigable from Sumeisat (the ancient Samosata), 1200 miles
above its embouchure; and even 180 miles higher up, is a river "of
imposing appearance," 120 yards wide and very deep. The Tigris is often
250 yards wide at Diarbekr, which is not a hundred miles from its
source, and is navigable in the flood time from the bridge of Diarbekr
to Mosul, from which place it is descended at all seasons to Baghdad,
and thence to the sea. Its average width below Mosul is 200 yards, with
a depth which allows the ascent of light steamers, unless when there is
an artificial obstruction. Above Mosul the width rarely exceeds 150
yards, and the depth is not more in places than three or four feet. The
Euphrates is 250 yards wide at Balbi, and averages 350 yards from its
junction with the Khabour to Hit: its depth is commonly from fifteen to
twenty feet. Small steamers have descended its entire course from Bir to
the sea. The volume of the Euphrates in places is, however, somewhat