and positions of ^6 double and triple stars ^ &c. 327 



No. VIII. R. A. 8^ 2"> ; Decl. 18° 11' N. 



f Cancri ; I. 24. and III. 19 ; H. and S. 90 ; 



continued. 



Sir W. Herschel, no measures could be procured, which is 



much to be regretted. 



The evidence for the motion of the more distant star C will be 

 found in the Philosophical Transactions, 1824, Part III. p. 115. 

 The change of quadrant— the great amount of the motion 

 (23° 42' in 40^ years) and the circumstance of an error to that 

 amount, or anything like it, being perfectly impossible from 

 the considerable distance of the stars ; add, too, the regular 

 gradations by which the change appears, from several inter- 

 vening observations, to have taken place ; all these consi- 

 derations place the motion of the distant star beyond dispute, 

 and the present measures confirm it, the angle 67° 55' sf 

 compared with that of 1822 (68° 17' sf) indicating a motion 

 still in the same direction. Its amount, it is true, is only 

 — 22' instead of — 1° 44' which the assigned velocity would 

 give, but this is as near a coincidence as we have a right to 

 expect in such small quantities. 



•If this be really a Ternary system connected by the 

 mutual attraction of its parts, its perturbations will present 

 one of the most intricate problems in physical astronomy. 

 The difficulty will not be diminished by the circumstance 

 of the rotations of the two small stars about the large one 

 being (apparently at least) performed in opposite directions, 

 being the reverse of what obtains in our planetary system, 

 or by that of the deviations of the relative angular velocities 

 from Kepler's law, being such as to indicate either great 

 masses in all the three bodies, great excentricities in their 

 orbits, or a different law of gravity from what obtains in our 

 system. (H.) 



