l6 CHALLENGER 



the exact time at which this reading is taken. This is known as 

 a true bearing between the points. Stations marked by flags on 

 poles, or by tripods boarded up or filled in with calico, are then 

 established, usually on the higher ground, throughout the area 

 to be surveyed. By measuring the many horizontal angles con- 

 tained by the numerous triangles thus established the relative 

 positions of all these points are found. The geographical position 

 of each can be found by referring all stations to the position fixed 

 by star sights and the position where the true bearing has been 

 observed. This framework is known as the triangulation and to it 

 all the details of the survey, soundings and topography are fixed 

 as the work proceeds. 



No really suitable place was found for a base on Paul Island 

 and so, when the boats had sounded out the channel, the ship 

 went through and came to anchor in Nain Bay at 9.30 at night, 

 one week out from St. John's, Newfoundland. Challenger^ s arrival 

 at Nain was popular with the few inhabitants of this little Hudson 

 Bay trading station, as she was the first steamer to get north 

 through the ice this year, and the mail she brought was very 

 welcome, Nain lies well protected from seaward by numerous 

 islands, the largest of which, Aulatsevik, lies to the north-east- 

 ward. A narrow channel, or 'run', as it is called, divides this 

 island from the mainland and leads to Port Manvers about 20 

 miles northward. Local opinion seemed to agree that the ship 

 could pass up inside this Port Manvers Run although there were 

 two 'rattles' to be negotiated. (A rattle is a narrow channel 

 through which the tidal stream flows so fast that an appreciable 

 noise is made by the water.) Local opinion also agreed that a flat 

 expanse of land lay on the south side of Port Manvers which 

 seemed suitable for the base measurement. There was no hope 

 of reaching Port Manvers by the outside route for some weeks, 

 pack ice being solid right into the coast of Aulatsevik. So on the 

 morning of Saturday, i6th July, the ship steamed up the Port 

 Manvers Run, experiencing no difficulty until the second rattle 

 was reached about two miles from Port Manvers. Ice floes were 

 drifting through the rattle on the tidal stream, so the ship was 

 anchored and a boat sent to investigate. She located a navigable 

 passage close to the eastern shore and later led the ship through, 

 but on rounding the point it was seen that the whole western 



