CATALOGUE OF POLAR STAKS. 



289 



As a further illustration of the application of formula? (54), (55), and (56), 



■ne compute the value of a for 1911 from the values of — for 1895, 1903, 1911, 

 ^ (It 



by formula (54); for 1887, 1895, 1903, and 1911, by formula (55); and for 1879, 



1887, 1895, 1903, and 1911, by formula (56). The value of j for 1911 is carried 



forward from that for 1907 by means of the third difference + 0'.003-41, giving 



~ = +6P.89817. 

 at 



1895 i\ = + 67.16557 



1903 4;j, = +258.13516 



1911 pI = + 61.89817 



Sum = +387.19890 



P3 = + 64.53315 



k. m. s. 



16 P,= +0 17 12.5304 



«^= 7 52 33.2626 



For 1911 a = 8 9 45.7930 



1887 2), = + 69.76200 

 1895 ^lh= +201.49671 

 1903 3/>3= +193.0(1137 

 1911 i>4= + 61.89817 

 Sum = +526.75885 

 P^= + 65.84486 



h. m. s. 



24P«= +0 26 20.2766 



«„= 7 43 25.5157 



For 1911 « = 8 9 45.7923 



1879 1 p. = + 506.02629 

 1887 32y),= +2232.40320 

 1895 12;;.^= + 805.98684 

 1903 32;), = +2065.08128 

 1911 7/),= + 433.28719 

 Sum'= +6042.78480 

 P, = + 67.14205 



ft. m. s. 



32 P, = +0 35 48.5457 



«„'= 7 33 57.2480 



For 1911 « = 8 9 45.7937 



