DEEP CURRENT MEASUREMENTS NEAR BERMUDA 
by RAYMOND F, McALLISTER 
INTRODUCTION, 
IT HAS BEEN CUSTOMARY FOR YEARS TO MEASURE 
DEEP OCEAN CURRENTS INDIRECTLY, DEDUCING THEM FROM 
DYNAMIC TOPOGRAPHY. JIORE RECENTLY THE JOG-LOG, PARA- 
CHUTE DROGUES AND NEUTRAL DENSITY FLOATS, ALONG WITH 
ANCHORED BUOY RECORDING STATIONS, HAVE BEEN USED. 
ALL OF THESE METHODS SUFFER FROM THE SAME 
DIFFICULTY: THEY FILTER OUT HIGH FREQUENCY FLUCTUA~ 
TIONS IN CURRENT SPEED AND DIRECTION, EITHER BY THE 
LONG TINE BETWEEN SUCCESSIVE RECORDINGS, BY MECHANICAL 
FILTERING DUE TO THE LONG CONNECTING LINE TO THE SUR-= 
FACE, OR BY THE DIFFICULTY IN OBTAINING ACCURATE GEO=- 
GRAPHIC LocaTron. THIS IS NOT TO SAY THAT THESE ARE 
NO? EXCELLENT METHODS OF MEASURING CURRENTS, BUT 
RATHER THAT THEY COULD NOT SATISFY THE OBJECTIVES OF 
THIS STUDY, FOR WHICH A CONTINUOUS RECORDING CURRENT 
METER WITH A HIGH SPEED OF RESPONSE TO CURRENT CHANGES 
WAS NEEDED. THIS REPORT DETAILS THE MET@R DEVELOPED 
AND SOME OF THE INTERESTING RESULTS ACHIEVEDe 
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