( ) 
Firft, he fuppofb, that the Velocity of the running 
Water is every where in a fubduplicate rafU of the 
Depth, and conrequencly the Quantities difcharged may 
be reprefented by the Parabolick Spaces, juft as in the 
cafe of the firtaple Motion of Water 
Secondly, that the Velocity of the dead Water, is the 
fame at all Depths, and equal to the greateft Velocity 
of the running Water. Wherefore the Quantity of dead 
Water difcharged may be reprefented by a Redangle, 
whofe Height reprefents the Depth of the ftagnant Wa- 
ter, and whofe Bafe is the greateft Ordinate of the 1 a- 
rabolick Space abovementioned. 
Having thus contrived a way of reprefenting the 
Quantities of Water difcharged by the mixt Motion, 
as had been done before for the fimpJe Motion of Wa- 
ter, our Author obfervcs that the Velocities of the Wa- 
ter iftuing out at different Depths, and confequently 
the Parabolick Spaces reprefenting the Quantities of W^a- 
cer expended, muft be lefs in the mixt, than in the 
fimple Motion. 
In order therefore to find a general Rule for deter- 
mining the Proportion between the Parabolick Spaces, 
which reprefent the Quantities difcharged by the mixt 
and fimple Motion, or between the Parameters of ihofe 
Patah/as, he draws fome Obiervations from the foregoing 
Experiments, by the help of which he hopes fuch a 
Rule may be found out. 
Firfly he obferves that, if the Depth of the running 
Water continue unchanged, a greater Depth of dead 
Water requires a lefs Parameter. 
Secondly y Thar this Parameter does not decreafe in 
fd great a Proportion, as the Depth of the Water in- 
cteafes- 
Thirdlyy That, if the Depth of the dead Water de- 
creafe, or the Depth of the running Water increafe in 
fuch 
