278 EEPOKT— 1891. 



fairly closely passed, and the temperature of the water not fall 

 below 45°Fahr. when alongside it. That would be a stray berg 

 that had got into an eddy current from its ice-bearing one. On 

 the other hand, if surface temperature be constantly and care- 

 fully taken — sa}', every hour— and the water is found to drop 

 suddenly five or six degrees, so as to reduce its reading to below 

 40'^ Fahr. in two or three hours, it conveys in the clearest 

 manner a warning, which, especially in the night-time or foggy 

 weather, is not to be disregarded with impunity ; and tlius far the 

 thermometer is a valuable instrument, regarded as a means of 

 detecting ice, by showing that a vessel has entered a polar 

 current which in all probability contains icebergs. But it will be 

 found in practice that a sensitive thermometer exposed to the 

 air, and frequently consulted, will give at least equally reliable 

 information ; and a fluctuation of two degrees, even, in a ther- 

 mometer so exposed below the normal temperature conveys 

 unmistakable information. This, at least, is certain : that the 

 darkest night cannot conceal ice, provided that it be above 

 water and the atmosphere fairly clear. And if the condition of 

 weather does not comply with this one requisite when the 

 warnings of ice are present, the sooner any ship stops the better 

 for all on board her. In even moderately clear weather it can 

 always be seen by a good look-out in time to avoid it. 



In clear calm weather, also, ice will give back a distinct echo 

 to the sound of a steam-whistle ; but, until it is ascertained 

 beyond doubt that fog does not vitiate this safeguard, it is not 

 worthy of being implicitly trusted. 



Therefore, when the question of the best route over this 

 vast tract of sea is under consideration, one is brought to face 

 one of two alternatives : whether will you choose a lower 

 parallel, on which you will run hundreds of extra miles, with 

 the chance of danger not well indicated, supposing it to be 

 present, in the form of ice carried to the northward and dis- 

 tributed over a wide tract by an eddying and weakening current ; 

 or will you, by boldly facing the difficulty, cut through that 

 current at a comparatively narrow part, where all the indica- 

 tions of any trifling danger that may exist are well defined, 

 palpable, and to be easily guarded against, whilst by so doing 

 you save some hundreds of miles ? The answer can scarcely be 

 doubtful : the difficulty, if fairly met, is conquered at once, and 

 practically is not worth more tlian fair consideration. 



Furthermore, it must be admitted that, considering the data 

 at his disposal nearly forty years ago, Mr. Towson made a 

 wonderfully correct estimate of what the dangers amounted to 

 oil this route, and, in fixing upon 57° S. lat. as the proper 

 latitude in which to run for Cape Horn, came to a conclusion 

 which cannot be found fault with, and of which all recent ex- 

 perience has proved the correctness. 



