NEW ZEALAND— SOUTH ISLAND. 



429 



indented seaboard. As in the nortliern region, the New Zealand fiords, or sounds, 

 as they are here called, occur only at the issue or at the converging points, where 

 glaciers filled the primitive valleys, protecting them from the deposits of débris 

 which were formed round about wherever the surface was not covered with layers 

 of ice. Neither moraines nor alluvial matter could help to fill these profound 

 depressions, which were preserved in their original form by the frozen streams 

 occupying all their cavities. 



But as soon as the glaciers withdrew above sea-level and their lower reaches 

 became gradually converted into running waters, the levelling-up process set in. 

 Avalanches, landslips, torrents, marine waves, and currents combined to fill up the 



Fig. 185. — Beeaksea and Dusky Sounds. 

 Scale 1 : 600,000. 



Depths 



to 50 

 Fathoms. 



50 to 100 

 Fathoms. 



100 Fathoms 

 and upwards. 



12 Miles. 



basins, which thus became transformed at first to chains of lakes, then to swampv 

 tracts and fertile plains. All the fiords that formerly existed north of 44° S. lati- 

 tude have already been obliterated, and those still surviving are now all concentrated 

 in a space about 80 miles long in the south-west corner of South Island. The 

 largest, as was to be expected, are those which open exactly at the southern 

 extremity of the seaboard. Such are Preservation Inlet, Dark Cloud Inlet (Chalky 

 Sound), and Dusky Sound, which last has an area of no less than 80 square miles. 

 The northernmost fiord in New Zealand, or in any region of the southern hemi- 

 sphere, is Milford Sound, a magnificent sheet of water, in which are mirrored the 

 surrounding snowy crests, glittering peaks and verdant headlands. Sheer above 



