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9.— PASSAGES TO AND FEOM THE NOETHEEN 

 POETS OF AMEEICA. 



In the introductory remarks to this section of the work, we have alluded 

 to the principles of Great Circle Sailing, and have pointed out the advan- 

 tages which it possesses, not so much in the shorter distance which it gives 

 over the rhumb course, but in the scope it allows the navigator in the 

 choice of a parallel on which he can make a good passage, without 

 materially increasing the actual distance to be sailed over. 



" In no case can this be better exemplified than in the course over the 

 Northern parts of the Atlantic, between the British Isles and the Northern 

 American ports. We alluded (page 460) to a case, not impracticable, of 

 the courses between the Land's End and Gape St. John, in Newfoundland, 

 and showed that two courses might be taken not more than 35 miles 

 greater than the shortest distance, of exactly the same length, and yet be 

 330 miles apart in latitude in their greatest separation. 



An imaginative course will well explain this for our present purposes : — 

 From the Lizard to Sandy Hook, New York, the distance and true course 

 by Mercator's Chart are 2,952| miles S. 78° 51' W. But if a vessel 

 leaving the Lizard were to commence sailing N. 73° 24' 40" W., and 

 passing about 35 miles Southward of Cape Clear, gradually bearing to the 

 West, attaining a maximum latitude of 51° 56' 30", in long. 26° 27' 20' W., 

 and then, if it were possible, approach New York on a S. 54° 36' W. course, 

 she would sail over 2,865 miles, or 87|- miles less than the compass course. 

 This Great Circle course passes over Cape Bonavista and La Hune Bay in 

 Newfoundland ; St. Anne's Bay in Breton Island ; Pictou and Cape 

 St. Mary in New Brunswick ; near Boston ; and over New London, and 

 Long Island. 



A line of the length of 2,952^ miles, placed in a higher latitude than the 

 rhumb line, as shown in page 460, is just as much above the Great Circle 

 course in latitude as the latter is above that by compass. This corre- 

 sponding arc from New York leads considerably inland, intersecting 

 Chaleur Bay, Cape Bonaventura in Gaspe Bay, Anticosti, passes 45 miles 

 N.W. of the Strait of Belle Isle, approaches within 189 miles of Cape 

 Farewell, Greenland, attains a maximum latitude of 57° 12' N., and inter- 

 secting the S.W. part of Ireland, at Kinsale, reaches the Lizard in a S.E. 

 direction. These two lines, of the rhumb and the corresponding arc, are 

 upwards of 700 miles apart at the greatest deviation from each other. 



With these considerations so manifest, we shall be better prepared to 

 imderstand that a higher latitude than the usually received one cannot, of 

 itself, be disadvantageous ; and by the excellent observations of Captain 

 Hare, presently given, will be more clearly evident. 



By referring to the Chart, it will be seen, that from the Land's End to 

 St. John's, Newfoundland, the true bearing is W. 4° 30' S. ; and from the 

 same point to Cape Sable, it is about W. 9° S. But the circumstances of 

 navigation in general render a direct course more tedious and difficult than 

 a circuitous route, and the best passages have been made by pursuing a 

 high Northerly course. 



