CHAPTERS ON THE STARS. 377 



which stars might be found. In order to include every star in some 

 constellation, the figures have been nearly ignored by modern astrono- 

 mers, and the heavens have been divided up, by somewhat irregular 

 lines, into patches, each of which contains the entire figure as recog- 

 nized by ancient astronomers. ■ But all are not agreed as to the exact 

 outlines of these extended constellations, and, accordingly, a star is 

 sometimes placed in one constellation by one astronomer and in another 

 constellation by another astronomer. 



The confusion thus arising is especially great in the southern 

 hemisphere, where it has been intensified by the subdivision of one 

 of the old constellations. The ancient constellation Argo covered so 

 large a region of the heavens, and included so many conspicuous stars, 

 that it was divided into four, representing various parts of a ship — the 

 sail, the poop, the prow and the hull. 



Dr. Gould, while director of the Cordoba Observatory, during the 

 years 1870 to 1880, constructed the TTranometria Argentina,' in which 

 all the stars visible to the naked eye more than 10 degrees south 

 of the celestial equator were catalogued and mapped. He made a 

 revision of the boundaries of each constellation in such a way as to 

 introduce greater regularity. The rule generally followed was that 

 the boundaries should, so far as possible, run in either an east and 

 west or a north and south direction on the celestial sphere. They 

 were so drawn that the smallest possible charjge should be made in the 

 notation of the conspicuous stars; that is, the rule was that, if possible, 

 each bright star should be in the same constellation as before. The 

 question whether this new division shall replace the ancient one is one 

 on which no consensus of view has yet been reached by astronomers. 

 Simplicity is undoubtedly introduced by Gould's arrangement; yet, in 

 the course of time, owing to precession, the lines on the sphere which 

 now run north and south or east and west will no longer do so, but 

 will deviate almost to any extent. The only advantage then kept 

 will be that the bounding lines will generally be arcs of great circles. 



When the heavens began to be carefully studied, two or three 

 centuries ago, new constellations were introduced by Hevelius and other 

 astronomers to fill the vacant spaces left by the ancient ones of 

 Ptolemy. To some of these, rather fantastic names were given; the 

 Bull of Poniatowski, for example. Some of these new additions have 

 been retained to the present time, but in other cases the space occupied 

 by the proposed new constellation was filled up by extending the 

 boundaries of the older ones. 



At the present time the astronomical world, by common consent, 

 recognizes eighty-nine constellations in the entire heavens. In this 

 enumeration Argo is not counted, but its four subdivisions are taken as 

 separate constellations. 



