From (8) the discharge is

Q2 = (2/3)cB [root](2g) [H2^(3/2) - H1^(3/2)].

Hence, for the same value of c in the two cases,

Q2/Q1 = (2/3)[H2^(3/2) - H1^(3/2)] / [(H2 - H1)[root]{(H2 + H1)/2}].