ON THE NOMENCLATURE OF THE STARS. 3? 



extension of the boundaries warranted by Ptolemy's description of the position 

 of the stars in that constellation *. 



Much confusion has also arisen from inattention to a regular classification 

 and arrangement of certain clusters of stars that lie near the adjoining con- 

 fines of two contiguous constellations ; such as the cluster of stars about the 

 head of Serpens, which are strangely intermixed with the stars that are con- 

 sidered to be in the arm of Hercules : and many similar cases may be seen in 

 Monoceros and Hydra, Draco and Cepheus, Auriga and Camelopardus, Libra 

 and Hydra, Hercules and Ophiuchus, Vulpecula and Cygnus, &c. 



But the most striking proof of the inattention of map- and globe-makers to 

 accuracy of arrangement, occurs in the cases where the author of the catalogue 

 has placed the same star in two distinct constellations, and where unfortu- 

 nately (in constructing the map) the erroneous one has been selected for its 

 location. A singular case of this kind occurs with Flamsteed's 25 and 27 

 Aquarii, which are the same stars as 6 and 11 Pegasi. The map-maker has 

 correctly placed the stars in the head oi Aquarius, as drawn on the map ; but 

 then, as if doubtful of such a step, or desirous of preserving the double inter- 

 pretation, has extended the boundary line of Pegasus so as to embrace it 

 within the limits of that constellation. 



Cases of such double insertions in a catalogue are not to be wondered at in 

 the early state of the science, where minute accuracy was not always attain- 

 able, nor the error always discoverable on account of the mode of classifica- 

 tion ; and we accordingly meet with a few of such cases in the catalogues of 

 Ptolemy and others. But in more modern times the error has arisen princi- 

 pally, if not solely, from the method of arranging the stars, in a catalogue, 

 under distinct and separate constellations, whereby the similarity of position 

 is not readily discovered ; and this will account for the synonyms that occur 

 in the catalogues of Flamsteed and Hevelius : but when discovered they ought 

 to be at once corrected, and not suffered to remain a perpetual blot in the 

 catalogue. The modern mode, however, of arranging the whole of the stars 

 in a catalogue, according to the order of their right ascension, without any 

 regard to the order of the constellations in which they may be placed, pre- 

 vents the occurrence of a similar inconvenience in future. 



But a like source of error arises, and frequently causes doubt and difficulty 

 to the map-maker, and even to the astronomer, when the authors of two dif- 

 ferent catalogues vary in their decision as to the constellation in which a star 

 should be located. Numerous instances of this kind may be seen in comparing 

 the catalogues of Hevelius and Flamsteed, or either of these with the cata- 

 logues of Piazzi or Taylor : which confusion has arisen from a want of a system 

 of well-defined and acknowledged boundaries to the respective constellations, 

 whereby the astronomer may know when he is correct in locating the observed 

 stars. Let any one examine the stars in Hevelius's first constellation {Andro- 

 meda), and he will there find that Flamsteed has placed some of them in Pe- 

 gasus, one in Perseus, and one in Lacerta ; whilst Piazzi places one of them 

 In Cassiopea. Those only who have to make frequent references to the class 

 of smaller stars, and are desirous of identifying them, and of comparing the 

 results of different observers, can justly appreciate the labour and inconveni- 

 ence that occurs from such a confused state of location. And with respect to 

 the map-maker, it is a forlorn hope to expect from him anything like regu- 

 larity, uniformity, clearness or precision so long as he continues the present 

 system of circumscribing every star with the boundary line of the constella- 



* An exception, perhaps, might here be made to Flamsteed's 11 Crateris, and which Bayer 

 has designated by the letter j3 : a star which Ptolemy places in Hydra, at the same time how- 

 ever describing it as ^terd Trjv pdaiv tov Kparrjpos. I have followed Bayer and Flamsteed. 



