A LIMNOLOGICAL RECONNAISSANCE 



13 



TABLE 9— SUMMER HEAT-INCOME, OKOBOJI LAKE 



This result, as well as that of the preceding table, gives 

 the number of calories in a volume of water whose base is 

 1 sq. cm., and whose total height is equal to the mean depth 

 of the lake. 



If the computation is made by single meters in the upper 

 water, the result is somewhat larger, as the following table 

 of the upper 20 meters shows : 



TABLE 10— SUMMER HEAT-INCOME BY SINGLE METERS 



m.-20 m. 



In table 10 the calories in the 10 m.-15 m. stratum and 

 in the 15 m.-20 m. stratum are greater when computed by 

 single meters than when the mean of the five temperatures 



