THE PROBLEM OF THE HULL AND ITS SCREW PROPELLER. 219 
(2) .'. Log h. p.¢g = Log H. P. — 2Log R — 1.0414 Log (SS) 1.5621 R 
(3) Log H. P.¢ =Log H. P.— 1.0414 Log (= ii =| 
e. h. p. 
Subtracting (3) from (2): 
Log h. p.¢ = Log H. P.z—3.5621R 
Log h. p.¢ = Log H. P.g—3.5621R 
1Bt 12), 
-.hpa= aaa 
Turning now to the apparent slips and revolutions, 
For ship: 
_s 1Bl leh Se aloe 
ion H. P 
For model: 
h.p.q X 10%; 
s=S 
h. p 
For ship: 
V 
Z; = 2.861 Log | —]} — .0788. 
v 
For model: 
Za arson vor - x R™) — .0788. 
iBL Je} 
h. pa = anes 
H. P. 
in, ju = R2 
V 
(4) Log s = Log S + Log H.P.4+ 2.861 Log om — .0788 — Log H. P. 
(5) Logs = Log S + Log H.P.z— 3.5621 Log R + 2.861 Log 2) + 2.861 x 1/2 Log R 
— .0788 — Log H.P. + 2 Log R. 
Subtracting (4) from (5) :— 
Log s — Log s = ~3.5621 Log R +: 1.4305 Log R + 2 Log R. 
Log s = Log s — .1316 Log R. 
S 
SR EIsIC 
For ship: 
Vv X 101.33 
is P x (1>s) 
