MAPS AND PLATES. 



To face 

 PLATE page 



I. TRACK OF H.M.S. ' LIGHTNING '1868 ... 59 



II. FIRST CRUISE OF H.M.S. ' PORCUPINE '1869 87 



III. SECOND CRUISE OF H.M.S. ' PORCUPINE '1869 95 



IV. THIRD CRUISE OF H.M.S. 'PORCUPINE' 1869 106 



V. TRACK OF H.M.S. ' PORCUPINE '1870 180 



VI. DIAGRAM OF THE 'PORCUPINE' SOUNDINGS IN THE ATLAN- 

 TIC AND IN THE F^ROE CHANNEL, SHOWING THE EELATION 



BETWEEN TEMPERATURE AND DEPTH, THE SERIAL SOUND- 

 INGS REDUCED TO CURVES. THE NUMBERS REFER TO THE 



STATIONS ON THE CHARTS, PLATES II., III., AND IV. ... 323 

 VII. PHYSICAL CHART OF THE NORTH ATLANTIC : SHOWING THE 

 DEPTH, AND THE GENERAL DISTRIBUTION OF TEMPERATURES 



FOR THE MONTH OF JULY 363 



VIII. MAP SHOWING THE GENERAL DISTRIBUTION OF THE TER- 

 TIARY, THE CRETACEOUS, AND THE JURASSIC SYSTEMS 

 IN THE NORTH-WEST OF EUROPE WITH REFERENCE TO 

 CONTOUR . . . 474 



