— 7 



The hydromotric observations are completed by diagrams 

 of the metereologic observations carried out at the Port 

 of Conception del Uruguay ( Sheets XI and XII ). With 

 their aid it can be seen that the direction of the reigning 

 winds and the general orientation of the river are the 

 same. Their intensity, frequency and duration are indi- 

 cated in sheet XII. 



The approximate velocity of the propagation of the 

 rises of the river between the principal stations conside- 

 red results to be: — between Paso de los Libres and Con- 

 cordia two days, between Concordia and Conception del 

 I Fruguay one dav. 



The hydromotric observations have also been utilised to 

 plot the corresponding heights of water for the Stations 

 Concordia and Concepcion del Uruguay (Sheet N° XIII). 



For the determination of the velocities of the current, 

 sections of velocity have been taken at the hydrometric 

 stations Nueva Escocia and Concepcion del Uruguay as 

 well as at the different bars of the river (Sheets XIV & XV ). 



The section at those two ports have allowed to plot the 

 curves of the discharges and of the mean and maximum 

 velocities in function of the heights observed for the Middle 

 and Lower Uruguay (Sheet XIII). These studies have 

 been carried out by the aid of a current meter system 

 Woltmann with electric contact. 



In consequence of the quickness with which these ob- 

 servations must be made in the River Uruguay, as great 

 variation of level may occur within 24 hours during the 

 periods of sudden rise of the river, they only consist in 

 seven or eight verticals in which at each meter of depth 

 velocities have been taken during intervals of two or three 

 minutes. 



The nature of the territory through which the River 

 Uruguay flows is fairly consistent and the great propor- 

 tion of mud which takes part in the formation of the is- 

 lands and submergible grounds of the banks, makes them 

 well able to resist the action of the current and explicates 

 the relative stability of the different channels of the river. 



The river bed of the River Uruguay is generally sand 

 but in the lower Uruguay between the mouth of the Rio 



METEREOLOGIC 

 OBSERVATIONS. 



VELOCITY OF THE 



PROPAGATION OF 



THE RISES OF THE 



LEVEL OF THE 



RIVER. 



VELOCITIES OF 

 THE CURRENT. 



Curves of Dicharge. 



METHOD USED FOR 



THE OBSERVATION 



OF VELOCITY. 



Mu.l. 



