united States Depa.tn.ent o£ the Interim Fred A. Seaton. Secretary 

 Fish and Wildlife Service. Arnie 3. Suonnela. Con.miss.oner 



160° 

 J» ^OAHU 



An announcement (which read as follows) was recently Issued by the 

 Bureau of Commercial Fisheries Biological Laboratory, Honolulu, concern- 

 ing an error in depths of reversal computed from the readings of unpro- 

 tected and protected reversing thermometers; 



"Recently, it was discovered that the depths of reversal of 

 the Hansen bottles., as calculated at the Honolulu Biological Laboratory 

 from temperature differences of unprotected ard protected reversing 

 thermometers J are in error. These depths, which are in excess of the 

 cbrrect depth, may be reduced to the proper value by the use of a cor- 

 rection factor, as described below. 



At the time the data processing system in use at this laboratory 

 was being establishedj a table of the factor l/(Qxf\i,) was prepared for 

 use In computing the depths of reversal from the readings of unprotected 

 thermometers; Q represents the pressure- constant of an unprotected ther- 

 mometer, and Pm represents the mean density of the water column above 

 the depth of thermometer reversal, which was taken to be 1 0303 in all 

 cases. An error occurred in the calculation such that, instead of 

 l/(Qxftn)t the table consisted of values of (l/Q)3flPni This error is 

 present in all of the depth data which have been published by this labo- 

 ratory under its previous name, Pacific Oceainic Fishery Investigations, 

 and under its present rame Horolulu Biological Laboratory up to and 

 Including 1960„ Therefore, ii making use of the data published by this 

 laboratory before 1961, all depths should be corrected by dividing each 

 *>y C^m) » wlilch is equal to 1.0615. Multiplication of all the published 

 depths by 0.942 will give the proper value for the depth of each observa- 

 tion." 



Subsequent analyses have showr. that the error described above is present 

 only in the data from those cruises made by vessels of the Bureau of 

 Commercial Fisheries Biological Laboratory Horolulu after Hugh M, Smith 

 cruise 20 (February-April 1953)- Cruises for which data containing this 

 error have beer, published are lifted below with the appropriate publica- 

 tion references. 



Special Scientific Report -Fisheries No. 238 

 WASHINGTON: SEPTEMBER 1957 



