Turbulence in the Ocean, 583 



temperature be AcosZ+Bsin/, the equation of heat trans- 

 ference can be written 



. (dA , dB • A C a • 7 -n 7x dl . 



k\ —r- cos /+ 7 — sin / 1 = l( —A sin / + B cos /) — a~ 



\dz dz /J '<& 



where the lower- limit of the integral is z= — ao 5 since A and 

 B both tend to zero there. d?Z/rf£ is the sun's mean motion, 

 m say. Equating coefficients of cos I and sin I we have 





*5 = 



The two integrals and the differential coefficients were 

 found roughly from the curves ; the places where the 

 integrals changed sign seemed fairly determinate, so that 

 the maxima and minima of A and B could be placed 

 moderately accurately. New curves were drawn to fit these, 

 and from them the integrals and differential coefficients 

 were redetermined ; thus two estimates of k were obtained 

 for each depth, and their agreement gave a test of the 

 adequacy of the theory. The following table indicates the 

 results of this rough interpolation. 



Depth 

 (metres). 



A. 



(in degi 



rees C). 



dA 



dz ' 



Jb*. 



k 



n ' 



d,B 



dz " 



Ja*. 



k . 

 n 







-4-5 



-0-7 



-15-0 



-248 



1-6 



5-0 



-74 



1-5 



50 



-0-5 



-17 



- 19 



182 



9-5 



Small 



Small 



? 



100 



-0 05 



-1-5 



- 0-6 



-100 



16-6 



-0-5 



65 



13 



150 



4-0-3 



-1-2 



- 0-5 



- 32 



64 



-0-8 



55 



0-9 



200 



4-0-6 



-0-5 



- 04 



- 14 



3-5 



-2-5 



35 



1-4 



250 



4-0-8 



4-0-2 



Small 



11 



? 



-0-3 



Small 



? 



800 



-0 05 



4-0-1? 



Small 



3? 



s 



0-3 



-30? 



? 



In this table dk\dz and dB/dz are measured in degrees 

 centigrade per hundred metres : \ Adz and ^Bdz are in 

 degrees multiplied by metres. Thus k/n is in square deka- 

 metres. Taking n to be 2 X 10~ 7 /1 second, and adopting for 

 each depth the average of the two values of k obtained, we 

 have the following values of k in cm. 2 /sec. : — 



Depth (in metres)... 50 100 150 200 ' 250 300 



k (iu cm. 2 /sec.) 031 1*90 3'00 1-33 0'49 ? ? 



The value of these results must not be exaggerated ; but 

 if the theory were seriously incorrect it is very unlikely that 



