1838.} Motion of the Solar Si/stem in Space, 399 



A. R.^ and draw the line VI— XVIII. If we assume the point N, to 

 which the motion of the solar system is directed, to be situated any 

 where in the direction P XVIII, it will at once represent the nature 

 of the above tables; for, the effect of advancing to any point N, being to 

 increase the are N S to N S', in which S S'- M sine N S; its effect 

 between ISA. and 6A. is to increase the right ascension; whereas 

 between 6/i. and 18/«. it should diminish it to the same extent: if we 

 now assume some position for N, and compute the value of M frorai 

 the proper motion in A. R. at I4/i. for instance ; and then compute 

 the same from the declination for 6^. and 13^.; we can, by the me- 

 thod of trial and error, discover the position of N which best suits 

 all the observations; from a few computations in this way^ the dis- 

 tance of N from P comes out between 23o and 24o, and the value 

 aw = +, "063, and s. which is immediately deduced = +, "0527. But the 

 point at ISA. A. R. and 23^ or 24^ N.P.D.is the pole of the Ecliptic ! ! ! 

 and the value for 5 just formed agrees almost to identity with that 

 formed at page 397} hence we come at once to the important and in. 

 some respects unexpected conclusion — that the solar system is in 

 motion ; and that the motion is directed towards the North Pole of the 

 Ecliptic. Could we form any approximate idea of the average dis- 

 tance of the fixed stars, we should be tempted at once to compute in 

 what time our system would be able to make the acquaintance of 

 her still distant neighbours ; but, in default of this information, it will 

 not be uninteresting to know how the case stands. Supposing the 

 fixed stars to be situated at such distance that the earth's orbit 

 subtends an angle of 1" only — and modern observations fixes it within 

 this limit— then the motion above indicated, amounts to 11,970,000 

 miles in a year; from which we readily discover, that the solar system, 

 under any circumstance of distance^ at its present rate of movements^ 

 will require 31,176,977 years to reach the nearest fixed stars* 



