MEAN TEMPERATURE 0 F THE 0 C E /N 
Tlie "Voyage of HALS “ClialLeiiger 
ISOTHERMAL LINES 
SHOWING THE MEAN TEMPERATURE (FAH?) 
OF THE OCEAN AT 
DEPTH OF IOO FATHOMS , 
Tt act of H.M. S. I 
Is othermals above' Average shown in 
