MOTION OF THE STABS. 287 



falls within a quadrangle, whose extremes are, R. A. 258 C 40', 

 and Decl. 30 40'; R. A. 258 42', Decl. + 30 57'; R. A. 259 

 13', Decl, -I- 31 9'; R. A. 260 4', Decl. + 30 32'. 



It still remained to inquire what the result would be 

 if the observations were directed only to those stars of the 

 southern hemisphere which never appear above the horizon in 

 Europe. To this inquiry Galloway has devoted his especial 

 attention. He has compared the very recent calculations 

 (1830) of Johnson at St. Helena, and of Henderson at the 

 Cape of Good Hope, with the earlier ones of Lacaille and 

 Bradley (1750 and 1757). The result 88 for 1790 was, R. A. 

 260 0'* Decl. 34 23'; therefore for 1800 and 1850, 260 5' 

 -f 34 22' and 260 33', + 34 20'. This agreement with the 

 results obtained from the northern stars is extremely satisfactory. 



If then the progressive motion of our solar system 

 may be considered as determined within moderate limits, 

 the question naturally arises : Is the world of the fixed 

 stars composed merely of a number of neighbouring partial 

 systems divided into groups, or must we assume the 

 existence of an universal relation, a rotation of all self-lumi- 

 nous celestial bodies (suns) around one common centre of 

 gravity which is either filled ivith matter, or void? 

 We here, however, enter the domain of mere con- 

 jecture, to which, indeed, it is not impossible to give a 

 scientific form, but which, owing to the incompleteness of 

 the materials of observation and analogy which are at pre- 

 sent before us, can by no means lead to the degree of evidence 

 attained by the other parts of astronomy. The fact that we are 

 ignorant of the proper motion of an infinite number of very 

 small stars from the 10th to the 14th magnitude, which appear 

 to be scattered among the brighter ones, especially in the im- 

 portant part of the starry stratum to which we belong, the 



33 Galloway, on the Motion of the Solar System, in the 

 Philos. Transact. 1847, p. 98. 



