170 



Lunar Hovjr^ 



100,000 



s 00,000 feet 



Instant aneooa p'rofilcs. 



FiGUEE 55. — Frictionless tides and currents in canal connecting a tidal with a tideless sea. 



334. Meeting the tides. — If the tides at the two entrances are identi- 

 cal in range and in timing, equations (244) and (245) further reduce to : 



y=Ao cos (a^+ao)[sin (1 — jj/Z)7 + sin (2;/iy)7]/sin y (246) 



v=(g/c)AosiDL (a^+Q:o)[cos {l—xlL)y — cos (a;/Z)7]/sin y (247) 



and at the middle of the canal : 



'^=(9/c)Ao sin (a^+Q:o)(cos )^7 — cos 7^7) /sin 7=0 



