195 



coincide with the ends of the subsections, at stations 40, 80, 120 

 and 160. 



377. Initial com.ponent tides at the storage stations. — -These are com- 

 puted from equations (273) and (274): 



Asinai = 1.732 A cos ai = 1.0 



Ao sin aQ = Ao cos a:o=4.0 



1.732 —3.0 



Initial component tides 



378. Coordinate currents in middle subsection. — The head in the 

 middle subsection is com.puted from the component tides at stations 

 80 and 120. 



Hsin H°=A sin auo-A sin a8o=1.039-0.693 = 0.346 

 HcosH°=Acos ai2o-^sin a8o=2.2-2.8=-0.600 



tan iJ° = 0.346/(-0.600) = -0.577 H° = 180° -30° = 150° 



H=O.Q/cos 30°=0.693 



Then S'=i?/;=0.693/40,000=0.00001732. And from the given data: 



r=30 (7=120 r5'=0.0005196 



The coordinate components of the current in the middle subsection 

 are computed as described in paragraphs 246 and 248: 



logr*^=6.71567-10 logVcos <^ = 9.93987-10 



logvV*S=8.35783— 10 



log 1.0854= .03559 

 log C=2.07918 



log P= .47260 

 log»S=5.23855-10 

 log P/*5= 5.23405 

 From table IX: 0=4O°.7=4O°4O' 



log P= .47260 



log Bo = .41247 

 Bo =2.580 



From equation (162): 



^o=i?°-0-9O° 

 = 150°-40°40'- 

 = 19°20' 

 Bo cos |So=2.440 

 Bo sin |So=0.854 



•90' 



