PRODUCTION AND COLLECTION OF SEED OYSTERS 
245 
with the neap tides of the moon’s first and third quarters. During the spring tides 
the flood current in Milford Harbor attains a maximum velocity of 33 centimeters 
(1.1 feet) per second and the ebb current 45.7 centimeters (1.5 feet) per second. 
With neap tides considerably less water passes in and out of the harbor and the 
velocity of the flood current at strength is 24.4 centimeters (0.8 feet) per second and 
the ebb current 40.6 centimeters (1.3 feet) per second. The tidal currents here are 
Figure 28.— Temperature of the water, pH, and salinity during tidal cycle, Milford Harbor 
of the rectilinear or reversing type; that is, the flood current running in for a period 
of approximately 5 hours and 30 minutes and the ebb current r unnin g out for a 
period of 6 hours. The ebb current has a greater velocity and period of duration 
than the flood current because of the river water discharged into the harbor. Using 
the formula given by Marmer (1925) it is estimated that currents of such strength as 
those at the entrance of Milford Harbor would transport a floating object approxi- 
mately 21,100 feet during the ebb flow of 6 hours and return it but 15,600 feet during 
