426 Ship Waves 
of a semi-empirical nature, is introduced into the theory of ship waves to 
represent this effect. With certain assumptions, calculations are made 
for the wave profile for a simple model, and curves are also given; these 
are compared with available experimental data. It appears that, as a 
a rough estimate for such forms at moderate speeds, the efficiency of 
the stern is of the order of 60% of that of the bow. Curves are also 
drawn to show the corresponding change in the wave resistance. The 
introduction of the reducing factor leads to different wave resistances for 
a model going ahead and going astern, when the model is not symmetrical 
fore and aft; this is illustrated by calculations and curves for a particular 
case. 
Reprinted from ‘ Proceedings of the Royal Society of London’? 
Series A No. 868 vol. 149 pp. 417-426 April 1935 
HARRISON AND Sons, Ltd., Printers, St. Martin’s Lane, London, W.C.2 
407 
