— •) — 



Palmira has been approximately determined and also by 

 doing' so it has been possible to draw its longitudinal sec- 

 tion. - INSTANTANEOUS 



When the longitudinal section of this part of the river SECT,0N OF THE 



' = l PROPAGATION 



and the instantaneous sections of the maxima of the ordi- of the tides. 

 nary and extraordinary tides in every station has been 

 drawn, the propagation of the tidal wave appeal's very 

 distinctly. 



From the examination of this drawing results that at 

 Nueva Palmira the first high tide is the strongest, the 

 difference between both becoming less as they propagate in 

 the river Uruguay, but it also happens that they are 

 reduced into a single one, or that they are no longer felt 

 on account of the influence of the winds. 



It may also be observed that during the ordinary tides 

 the quantity of water discharged during ebb is greater than 

 that entering during flood, the contrary happening during 

 the extraordinary tides, when the river goes back to its 

 ordinary level after 3 or 5 days, as may be observed in the 

 curves representing the heights of the water, a circum- 

 stance which greatly favours navigation of the river I'm- 

 guay during the periods when the river is low. 



Observing those same curves, it may be seen that the 

 ordinary tides without wind and onl}^ caused by the 

 lunar atraction disappear near Nueva Palmira ( (5 or 10 

 centimetres of height) meanwhile the extraordinary tides 

 under the influence of the winds of the 2nd. and 3rd. 

 quadrant arrive easily at Concordia and may reach at 

 this port a height of more than one metre. slopes. 



The slopes corresponding to the different heights ob- 

 served in the various sections of the river Uruguay, have 

 also been determined (Sheet III and IV) and the mean slope 

 during ordinary high river results to be 0.06 mis. per ki- 

 lometer between Concordia and Nueva Escocia and0.015 

 cuts, between Banco Grande and Fray Bentos. 



