Feb. 1827. 



ADMIRALTY SOUND. 



59 



being shoal, — from the very slight tide-stream, — and from the 

 information of the Natives ; who evidently intended to tell us 

 we could not get out to sea, — that we did not consider it worth 

 while to make another examination. 



I have before observed that the strata of the slate rocks, in 

 the Strait, dip to the S.E. ; and I found that they dip similarly 

 all the way to the bottom of this inlet, which I named Admiralty 

 Sound. 



The north side, like that of the Gabriel Channel, is steep, 

 without indentations, excepting where there is a break in the 

 hills ; but on the south shore there are many coves, and bights, 

 the cause of which is shown in the accompanying imaginary 

 section of the Gabriel Channel. The same cause operates on 

 the outline of the north shore of the reach of Cape Fro ward, 

 westward as far as Cape Holland, where the rock assumes a 

 still more primitive form. Its general character, however, is 

 micaceous slate, with broad veins of quartz ; the latter being 

 particularly conspicuous at Port Gallant. 



The following slight sketch, intended to represent an ima- 

 ginary section of such an opening as the Gabriel Channel, 

 may also serve to give a general idea of many Fuegian ancho- 

 rages ; — of deep water passages existing between the almost 

 innumerable islands of Tierra del Fuego ; — and of the effects 

 of those sudden, and violent gusts of wind, — so frequent and 

 dangerous, — commonly called hurricane-squalls,* orwilliwaws. 



* No canvas could withstand some of these squalls, which carry spray, 

 leaves, and dirt before them, in a dense cloud, reaching from the water to 

 the height of a ship's lower yards, or even lower mast-heads. Happily their 

 duration is so short, that the cable of a vessel, at anchor, is scarcely 

 strained to the utmost, before the furious blast is over. Persons who have 

 been some time in Tierra del Fuego, but fortunate enough not to have 

 experienced the extreme violence of such squalls, may incline to think 

 their force exaggerated in this description : but it ought to be considered, 

 ^^hat their utmost fury is only felt during unusually heavy gales, and in 

 particular situations ; so that a ship might pass through the Strait of 

 Magalhaens many times, without encountering one such blast as has 

 occasionally been witnessed there. — R.F. 



