36 PROCESSING OCEANOGRAPHIC DATA 



Table ni.— EXPANSION CORRECTION, C, FOR UNPROTECTED THERMOMETERS OF X=6,100 FOR VALUES OF 



r:+V'„ AND 7\-l., 



(From Schumacher, 1923) (4) 



C- ^ 



where, 



7'^ = reading of the unprotected reversing thermometer, 

 <„ = corrected reading of the auxiliary thermometer, 



F„ = volume of mercury below 0° C. mark in the reversing thermometer, expressed in degree units, 

 ?'„ = corrected reading of the protected reversing thermometer, 

 if = reciprocal thermal coefficient of expansion, taken equal to 6,100. 



Example: 



Given, Ti = 5.9r C, l'„=82° C, T„=3.70° C, and <„=14.8° C. 



Then, Ti+V,= S7.9i° C. and 3'„-(„=-ll.r C. 



From table III, C= —.16° C. (Expansion correction, C, will have the same sign as r„-<„.) 



