304 



Africa. These singular hypotheses are mentioned by all the 

 historians of that time. (Pet. Martyr., Ocean, Dec. 1. lib. 

 vii, p. 77. Gomara, Hist gen., cap. viii, p. 110. Herrera, 

 Dec. 1, lib. iii, cap. xii.) 



But what observation of the polar star could induce Chris- 

 topher Columbus to adopt such strange ideas ? Ferdinand 

 Columbus explains this in the life of his father (Churchill's 

 Collection, Vol. ii, p. 583). The admiral had observed, in 

 the latitude of the Azores, the meridian altitude of the po- 

 lar star above and below the pole. The difference of these 

 two altitudes was 5° 5 and this gave 2° 30' for the distance of 

 the star from the pole ; while, by a trigonometric calculation, 

 it ought to have been at that time 3° 24' 30*. There was 

 an error therefore of 54' minus. Columbus judged of the 

 passage of the star over the meridian by the position of the 

 Great Bear. When the wain was east, or west, he considered 

 it as indicating the passage of the star over the meridian ; but 

 this indication being very uncertain, Columbus was not sure 

 of observing when the polar star was in the meridian j the 

 inferior altitude must have been too great, and the superior 

 too little 5 and this explains why Columbus found a differ- 

 ence of 5° only between the altitudes. 



Under the torrid zone, at about 7° or 8° of N. latitude, he 

 found the pole star 11° above the horizon, at it's superior 

 meridian, and only six when it was in declination, or at the 

 altitude of the pole, which gave him a polar distance of 5o. 

 Here Columbus supposed again, that the pole star was in 

 the superior meridian, when the wain was in the west ; but 

 as he could not perceive the pole star as it's inferior meri- 

 dian, because it was too low, he observed the altitude when 

 the wain was in the superior meridian, and indicated the 

 declination of the star. The pole star appeared to him 

 again at the altitude of 9°, when the wain was in the inferior 

 meridian, and consequently not visible, because of the small 

 elevation of the pole. 

 If the constellation did not indicate with precision the 



