322 : The Atlantic 



nor adequate. The device does not look like a plow and it does 

 much more than any land plow is expected to do. The submarine 

 plow is actually a huge structure, many tons in weight, which per- 

 forms a whole series of useful operations. In use, it is lowered to the 

 bottom and dragged along behind the cable-laying ship by special 

 towing hawsers. The cable to be laid is threaded through the plow 

 with a minimum of strain or tension. The plow handles the whole 

 laying operation. As it is dragged along it first digs a deep trench 

 in the bottom of the sea. It then deposits the cable in the trench and 

 finally closes the trench again and buries the cable. When deep water 

 is reached, plowing is discontinued and the submarine cable laid in 

 the usual fashion. 



Ships' anchors and fishing gear are not the only hazards suffered 

 by the cables. At the American end near Newfoundland, cables have 

 been subject to damage and rupture by icebergs grounding in shallow 

 waters. Even in deep waters on the bottom of the sea cables are not 

 entirely free from unusual accidents; submarine earthquakes and 

 submarine volcanic activity are believed to have accounted for a 

 succession of accidents to the cable services. 



The Great Eastern was the first successful cable-laying ship. Of 

 course, she disappeared from the scene a long time ago, but undoubt- 

 edly she demonstrated the advantages of creating a special type of 

 vessel to lay and maintain submarine cables. The cable ship has 

 developed into a special type of vessel, very ingenious in design and 

 almost a museum of mechanical inventions. Some such ships have 

 been built by the cable companies themselves, others have been con- 

 structed by companies that specialize in laying and maintaining 

 cables, selling their services to the operating company. A modern 

 cable ship called the Dominia is a good representative of one of the 

 vessels in the latter kind of service. Though not an excessively large 

 vessel, she is so well arranged and equipped that she can accommo- 

 date 3,000 miles of modern submarine cable; that is enough to reach 

 across the Atlantic. 



Such a cable ship is strictly a business undertaking. Her business 

 purpose is to lay and maintain cable services. The cable ship is de- 

 signed so that she can, if necessary, stay at sea for long periods of 

 time and in all kinds of weather. She is equipped so that she can 

 reach and study the ocean bottom even at great depth and under 

 adverse conditions. The cable ships and cable companies have a com- 

 mercial interest in all that pertains to oceanography and they are 

 eager consumers of information about the sea such as is supplied by 



