ROUTE SELECTION AND CABLE LAYING 295 



weather of unpredictable and frequently unpleasant nature. The bridg- 

 ing of this required the laying of two one-way cables over carefully 

 selected routes, using an available cable ship. And the presence in these 

 cables of 102 flexible repeaters posed problems quite unique for such 

 long and deep cables, as also did the need for trimming the system equal- 

 ization during laying so that transmission over the completed system 

 would fall within the prescribed limits. 



From Terrenceville, Newfoundland, to Sydney ]Mines, Nova Scotia, a 

 single cable, 270 nautical mile path was required through Fortune Bay 

 and across Cabot Strait. While this water is considerably shallower, here 

 again a relatively conventional cable laying problem was complicated 

 by the presence of repeaters which in this section were rigid units, 14 in 

 number.* Trimming of system equalization was also required. 



These cables were laid during the spring and summer months of 1955 

 and 1956. And the preparation for the laying required many months of 

 effort in fields which were for the most part quite foreign to the usual 

 scope of land wire telephone activity. Some appreciation of the prob- 

 lems encountered in this phase of the venture may be gained from the 

 following sections. 



NORTH ATLANTIC LINK 



Route Selection 



The first successful transatlantic telegraph cable was laid across the 

 North Atlantic in 1866. Since that date 15 direct cables have been laid 

 and 5 cables by way of the Azores. The approximate routes of these 

 cables are shown in Fig. 1. It is at once evident that the shortest and 

 possibly the best routes were already occupied so that selection of routes 

 for the two transatlantic telephone cables could be expected to present 

 some difficulty. 



Some of the more important considerations which guided the selection 

 were (a) route length, (b) clearance for repairs, (c) trawler and anchor 

 damage possibilities, (d) terminal locations suitable for repeater sta- 

 tions, with staffing in mind as well as facifities for onward routing, due 

 consideration being given to the strategic aspects of the locations. 



Route Length 



Obviously, the shorter the length of a submarine route, the better. 

 In the present instance, any system length much in excess of about 2,000 



* Two additional repeaters are located in the 55 nautical-mile section which is 

 trenched in across Newfoundland from Clarenville to Terrenceville. 



