1834. CLIMATE — BANKS — TIDES. 339 



summer the heat is scorching, but not sultry ; and in winter, 

 though the weather is sometimes searchingly cold, especially 

 during southerly winds, the air is always elastic and whole- 

 some. Changes of wind are sudden, and cause rapid, though 

 not very great, variations of temperature. Sometimes the sky 

 is slightly or partially overcast, occasionally clouded heavily ; 

 but on most days there is bright sunshine, and a fresh or strong 

 westerly wind. 



The confluence of a continental torrent of fresh water, with 

 great tides of the ocean, which here rise forty feet perpendicu- 

 larly, has embarrassed the mouth of the Santa Cruz with a 

 number of banks. They are all composed of shingle and mud, 

 and alter their forms and positions when aff'ected by river- 

 floods, or by the heavy seas caused by south-east gales. 



Into the entrance of the Santa Cruz, the flood-tide sets 

 about four knots an hour ; one may say, from two to five 

 knots, according to the time of tide, and the narrower or 

 broader part of the opening ; and outwards, the water rushes 

 at least six knots on an average in mid-channel. There are 

 places in which at times, when acted upon by wind or unusual 

 floods, it runs with a velocity of not less than seven or eight 

 •knots an hour — perhaps even more; but near either shore, and 

 in bights between projecting points, of course the strength of 

 the outward as well as inward current is very inferior. 



In such a bight, almost under some high cliff's on the south- 

 ern shore, the Beagle was moored, and it is easy to conceive 

 the different views presented in this situation, with forty feet 

 change in the level of the water. At high water, a noble river, 

 unimpeded, moves quietly, or is scarcely in motion : at other 

 times, a rushing torrent struggles amongst numerous banks, 

 whose dark colour and dismal appearance add to the effect 

 of the turbid yellow water, and naked-looking, black, muddy 

 shores. 



The boats sailed on between some of the banks, with a fresh 

 southerly wind, disturbing every where immense flights of 

 sea-birds. Now and then a monstrous sea-lion lifted his un- 

 wieldy bulk a few inches from the stony bank, lazily looked 



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