INTRODUCTION 



THE sinking of the Titanic, although the greatest catastrophe 

 of the kind, is by no means an isolated case. Many other 

 large ships have been destroyed or lost at sea, some of them 

 having disappeared without leaving the least trace of what 

 had happened to them, but the number of ships, though very 

 considerable, which have been lost in the open sea by col- 

 lisions with other ships or with icebergs, is extremely small 

 in comparison with those which have been lost by running 

 on to rocks or running ashore in a fog. I have seen a chart 

 called the " Caviare " map, in which a little black dot repre- 

 sents the locality where a ship has been lost, and these little 

 black dots are so numerous about the coasts of England, 

 Ireland, Norway, Sweden and Denmark as to give the map 

 the appearance of a lot of caviare, consequently the name. 



Professor John Tyndall, " the poet of science," was in- 

 structed by the British Government to conduct certain experi- 

 ments with the view of obtaining the best means of preventing 

 ships from running ashore in a fog. After a great number 

 of lights, electrical and otherwise, had been tried with very 

 indifferent success, experiments were made with sound-pro- 

 ducing instruments, such as very large steam whistles, enormous 

 trumpets worked with compressed air, and a siren specially 

 constructed for fog-signalling and much used in the United 

 States. Guns were also used of various sizes and with varying 



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