570 WEST AND SOUTH PATAGONIA. 
Of the archipelago of Madre de Dios we know very little. It 
has probably many deep openings on its seaward face, and is 
fronted by islands. and rocks. Its character is rocky and moun- 
tainous, and by no means agreeable. The wide and safe channel 
of Concepcion Strait separates it from the main land, which in this 
part is much intersected by deep sounds, the principal of which, 
the Canal of San Andres, extends to the base of the snowy range 
of the Cordillera, and there Lieutenant Skyring describes it to be 
suddenly closed by immense glaciers. 
Behind Hanover Island, which is separated from Madre de 
Dios by the Concepcion Strait, the main-land is very much inter- 
sected by sounds like the San Andres Channel, extending to the 
base of the Andes. 
South of Hanover Island is Queen Adelaide Archipelago, through 
which are several channels that communicate with the Strait of 
Magalhaens ; of which the principal, Smyth Channel, falls into 
the Strait at Cape Tamar. 
In the winter of 1829, Captain Robert Fitz-Roy, then command- 
ing the Beagle, in examining the Jerome Channel, which com- 
municates with the Strait in that part called Crooked Reach, 
discovered ‘ Otway Water,’ an inland sea fifty miles long, trending 
to the N.E., and separated from the eastern entrance of the Strait 
by a narrow isthmus ; the actual width of which was not ascer- 
tained, for in the attempt the boats were nearly lost. The south- 
eastern shore is high and rocky, and generally precipitous, but the 
northern is formed by low undulating grassy plains, free from 
trees, and precisely like the country about the eastern entrance of 
the Strait. At the north-west corner of the water a passage was 
found leading in a north-west direction for twelve miles, when it 
opened into another extent of water, about thirty-four miles long 
and twenty wide. This he called the Skyring Water. Its southern 
and western sides are bounded by mountainous land, but the 
northern shore is low, apparently formed of undulating downs and 
grassy plains, and in some places watered by rivulets. At the 
western extremity of the water two openings were observed, 
separated by a remarkable castellated mountain which was called 
Dynevor Castle. Beyond the southernmost opening there was no 
land visible, not even a distant mountain, which induced Captain 
Fitz-Roy to suppose that it was a ‘channel communicating with the 
