INTERESTING SCIENTIFIC WORK IN THE ARCTIC 211 



greatest and least altitudes were the same, or in other words, 

 vvl.en the sun did not change in altitude at all (except for its 

 change in declination in the sky), then was the 

 latitude 90 degrees, and the North Pole was 

 reached. It is readily seen that the small instru- 

 ments, the difficulty of determining horizon, and the 

 bitter cold combine to make the observations of no 

 great accuracy. Under such conditions it is ques- 

 tionable whether the position of the Pole could be 

 determined within ten miles !" 



Dr. Bernachi, physicist of the "Discovery" Ant- 

 arctic expedition, had this to say in regard to deter- 

 mining the location of the Pole: 



"At the poles of the earth, which are, mathe- 

 matically speaking, 'singular points/ the definitions 

 of meridians of North and South, etc, break down. 

 Here in this latitude we speak of the zenith directly 

 above our heads, and we are acquainted with the 

 Pole star (Polaris), so called because it almost coin- 

 cides with the Pole (celestial). There the celestial 

 pole and zenith coincide, and any number of circles 

 may be drawn through the two points, which have 

 now become one. The horizon and celestial Equator 

 coalesce, and the only direction on the earth's sur- 

 face is due south (or north at the South Pole) 

 east and west have vanished. A single step of the 

 observer will, however, remedy the confusion 

 zenith and Pole will separate and his meridian will 

 again become determinate. 



"At the North Pole the sun is visible above the 

 horizon for six months namely, from March 2ist 



o 1_ J ,.1 J * r ^ 1 J BAROMETER. 



to September 22d, the dates of the vernal and 



Instrument ly Queen 



autumnal equinox respectively, or when the sun & GO., Philadelphia. 



