SOUND-SIGNALS AT SEA. 95 



could not be heard through the air, yet could be with fair dis- 

 tinctness through the telephone. 



It is to be hoped that Prof. Blake may find opportunity to 

 continue his experiments, as he seems to be on the verge of pro- 

 ducing a practical and accurate instrument of value to mariners. 



Methods of using the Morse code of dots and dashes, as rep- 

 resented by long and short sounds of a fog-whistle or other simi- 

 lar contrivance, have been made public. The best one I have 

 met is that of Mr. Frank Purinton, of Providence, R. I., and it 

 is one of the best because it is the simplest. The idea is that, 

 when two ships meet in fog and make known their proximity to 

 each other by their fog-signals, each shall indicate to the other 

 the way she is steering by the length and the intermission of the 

 sounds made by her fog-signal. The following is the code in 

 part, the long blast being represented by the [ — ] dash, the short 

 one by the [-] dot ; 



The thirty-two points of the compass are represented by vari- 

 ations of the collocations of dots and dashes on the chart, and 

 with long and short sounds with intervals, in practice. These 

 signals can be given by the ordinary steam-whistle or by auto- 

 matic apparatus already invented and in use. Mr. Purinton 

 claims that his system will, if followed, prevent collisions. The 

 four cardinal points of the compass are so represented that op- 

 posite courses have opposite signals. One long sound means 

 north ; a short one, south. Two long sounds mean east, and two 

 short ones mean west. Other points of the compass are indicat- 

 ed by the synthesis or natural combination made by adding the 

 necessary cardinal signals for the intermediate points or courses. 



Another device, which may be called the echo-maker, that of 

 Mr. De la Torre, has been examined by a board of naval officers, 

 of which Commander Bainbridge Hoff, United States Navy, was 

 the head, and report was made to the Navy Department of a 

 somewhat favorable nature. It may consist of a flaring funnel 

 screwed on the muzzle of a rifle. It is operated by firing the 

 rifle in the direction of the supposed obstacle, such as a rock, an 

 iceberg, another ship, or a cliff. If the obstacle is there, the 



