THE STRAIT OF MAGELLAN. 65 



birds, apparently a species of petrel, were observed in the 

 vicinity of the ship, flying close to the water, moving their 

 wings rapidly, and then sailing along for a short space. We 

 altered course early in the afternoon, and shortly after got up 

 steam, as we hoped to enter the Strait next day. The follow- 

 ing morning was fine, bright, and cold. In the forenoon land 

 was sighted, the steep cliffs of Cape Virgins, on the northern 

 side of the entrance of the Strait being recognised at a distance 

 of about twenty miles, and not long after the long gravel- 

 spit of Dungeness could be distinguished. The land at first 

 presented a far from interesting appearance, resembling a 

 long low black wall, sloping down into the water at one end. 

 As we gradually approached the Cape, it assumed a variety 

 of forms, a phenomenon due to a species of mirage produced 

 by irregular refraction, and which we often subsequently 

 observed strikingly manifested in the eastern portion of the 

 Strait — distant mountain-peaks which in the ordinary condi- 

 tion of the atmosphere were invisible, being thrown up 

 against the sky, and the forms of small islands, boats, and 

 live objects, most singularly distorted. 



We entered the celebrated Strait, the scene of our future 

 labours for the next three years, early in the afternoon, with 

 what wind there was ahead and a strong tide running 

 against us, so that for some time we could only make be- 

 tween four and five knots an hour. In the eastern portion 

 of the Strait, I may here observe, the state of the tide de- 

 mands the careful attention of the navigator, on account of 

 the extent of the rise and fall, and the force of the ebb and 

 flow, which at one narrow part (the First Narrows, see map) 

 varies from five to eight knots, so as to be either a great 

 help or an almost insuperable obstacle to progression. As 

 we steamed slowly on our way, a variety of well-marked 



