Hydeography of the Stream 



69 



along the Straits of Florida suggests that this is in fact true, the wave 

 being of the Kelvin type (Thomson, 1871), and the range of tide being 

 greater along the United States coast than along the coast of Cuba or the 

 Bahamas. 



Electromagnetic measurement. — An interesting series of observations is 

 being accumulated through the co5peration of the Western Union Tele- 

 graph Company and the Woods Hole Oceanographic Institution. Elec- 

 trodes have been buried in the beaches at Key West and Havana, and 

 connected by a submarine cable. The potential developed by the water 



Fig. 4 1 . Mass transport of the Florida Current, as determined from electrical 

 measurements made on the Western Union Telegraph Company cable between 

 Key West and Havana by P. J. Moore and analyzed by Wertheim. 



moving through the earth's magnetic field is about 1 volt across the Straits, 

 and, under the assumption of a nonconducting bottom, indicates a volume 

 transport of approximately 26 x 10^ m.^/sec. The usefulness and feasibihty 

 of this kind of measurement will appear after more years of records have 

 been obtained. 



Data for about two years have now been obtained from the submarine 

 cable between Key West and Havana, across the Florida Current. 

 Electrical potential measurements covering several more years will prob- 

 ably be required before any definite conclusions can be drawn concerning 

 fluctuations in the actual volume transport. Wertheim (1954) has ex- 

 amined the first year's readings and has plotted the transport as a function 

 of time (fig. 41). Each point is a 24 hr. average of readings of potential 



