442 MR. RENNIE ON THE FRICTION AND RESISTANCE OF FLUIDS. 
0.618, and 0.611, for opening of 10 and for 5 centimetres, 0.618, 0.631, 
0.623 ; and for orifices of less dimension, the coefficient continually increased 
up to 0.698. 
That for water running over weirs, the mean coefficient was 0.400, which 
differs very little from that of Bidone. 
Hence we see little reason to deviate from the coefficients already given. 
