- 14 - 



square root of the vertical scale, -Jj . Thus 



v^ = Vy^ = 1/13.9 (4) 



This means that a velocity of 1 knot in the prototype is repre- 

 sented in the model by a velocity of I/13.9 knot or 3.65 cm/sec. 

 Since the available data on the velocities of flow in the proto- 

 type were given in knots, a ruler was constructed and graduated 

 in 3*65 cm intervals with tenths on one side and quarters on the 

 other so that the velocities in the model might be checked with 

 these lengths against the seconds beat of a break-circuit 

 chronometer made audible through a loud speaker. 



With the establishment of the time and length scales it was 

 possible to calculate the discharge scale for the rainwater and 

 bleed water. The kinematic discharge of rivers and industrial 



waste is scaled with regard to volume 



[^f yj 



per unit time 



(T ). Since T = L / Vy the total discharge scale Q is 



(Lp) ^r ^/9 ^ 



% = -f ^ = ^^^r^ = 7 ^5) 



^ / T \ r r 5.3 X 10*^ 



The discharge Q = Q„Q_, is the discharge into the model over the 

 same interval of time as is expressed for the discharge in the 



prototype. To make this perfectly clear, if the discharge of a 



n ^ 

 river is (10 ) m^mean solar day, the scaled discharge into the 



model must be Q x 10 m-^/mean solar day, not per model "day." 



