Let it be ſuppoſed, that the banks of the Rivers of which
we ſpeak be erected perpendicular to the plane of the up
per ſuperficies of the River.
we ſpeak be erected perpendicular to the plane of the up
per ſuperficies of the River.
SUPPOSITION II.
We ſuppoſe that the plane of the bottome of the River, of
which we ſpeak is at right angles with the banks.
which we ſpeak is at right angles with the banks.
SUPPOSITION III.
It is to be ſuppoſed, that we ſpeak of Rivers, when they are at
ebbe, in that ſtate of ſhallowneſſe, or at flowing in that ſtate
of deepneſſe, and not in their tranſition from the ebbe to the
flowing, or fr m the flowing to the ebbe.
ebbe, in that ſtate of ſhallowneſſe, or at flowing in that ſtate
of deepneſſe, and not in their tranſition from the ebbe to the
flowing, or fr m the flowing to the ebbe.