MEAN TEMPERATURE OF THE OCE^ 
Ts^ \ ol HM.S Challrng er 
100 
}40 
130 
Trark of H-M S.C 
^ ISOTHERMAL LINES 
SltOKIXf; THK MKAN TKMJ*KHAT1TRE (?’AH«) 
^ f)K THE OCEAN AT 
^ DEPTH OF 600 FATHOMS 
.// »$tt4 1 ' Avt't-ntff' kht-rtm i/i U*^l tht$M 
