ON THE NOMENCLATUBE OF THE STARS. 41 



sons may be adduced for considering such a change desirable) the first and 

 most important step towards it will be found in the present work itself, and 

 in the catalogues, now publishing simultaneously Avith it on the same system 

 of nomenclature*, Avhich clear the ground of all existing confusion ; and by 

 assembling into one distinct view, and under names and numbers at least 

 definite and recognised, all the individuals of which the new groups must be 

 composed, render it easy at any future time to pass, by a single table of 

 synonyms and by one decided step, from one to the other system, whenever 

 the convenience and consent of astronomers may dictate the propriety of a 

 change. Such views, if entertained, would render the nomenclature of the 

 present catalogues so far provisional that a more rational and convenient 

 system of groups (confined not to the southern hemisphere, but extending 

 oVer both) may yet be contemplated by astronomers. Nevertheless, so long 

 as the ancient system is at all retained, a general and scrupulous adherence 

 to the nomenclature here adopted is most earnestly recommended to the 

 astronomical world, as the only mode of escape from a state of confusion at 

 present quite intolerable. As regards the southern constellations, the follow- 

 ing are the principles proposed to be adhered to : viz. 



" 1°. That all the constellations adopted by Lacaille be retained, and his 

 arrangement of the stars preserved ; subject however to certain alterations 

 hereafter specified. 



" 2°. That all the stars, having a doubtful location, such as those which 

 Lacaille (after the manner of Ptolemy) has considered as ajuo'p^wroi (un- 

 formed), be included within the boundaries of either one or other of the con- 

 tiguous constellations, so as to preserve a regularity of outline. 



" 3°. That all the rest of Lacaille 's stars be placed within the boundaries 

 laid down by him, with the following exceptions : first, a few stars which are 

 located too far from the border of the constellations in which they are re- 

 gistered, to admit of an uniform contour of the lines ; secondly, such stars as 

 have been previously observed by Ptolemy or Flamsteed, and by them located 

 in other constellations, or which interlace and are confusedly mixed with such 

 previously observed stars f ; thirdly, the six stars that are placed by Lacaille 

 in the end of the spear of Indus, but which are now assumed to form part of 

 the constellation Pavo, in order to render the contour of these two constella- 

 tions less circuitous. 



" 4°. That the Greek letters, selected by Lacaijle, be adopted in prefer- 

 ence to those introduced by Bayer in the southern constellations ; but that 

 they be retained only as far as stars of the 5th magnitude inclusive. That 

 no Roman letters be used, except in the subdivisions of Argo, subsequently 

 mentioned. 



" 5°. That Argo be divided into four separate constellations, as partly 

 contemplated by Lacaille ; retaining his designations of Carina, Puppis and 

 Vela ; and substituting the term Mains for Pixis Nautica, since it contains 

 four of Ptolemy's stars that are placed by him in the mast of the ship. 



" 6°. That the original constellation Argo, on account of its great magni- 

 tude and the subdivisions here proposed, be carefully revised in respect of 



* Sir John Herschel here alludes to Lacaille's new catalogue of 9760 southern stars, and to 

 the catalogue of upwards of 48,000 stars, deduced from the ' Histoire Celeste,' both of which are 

 now printing at the expense of Government. — F. B. 



f " A single exception to this rule occurs in the case of the last star in the constellation 

 Piscis Australis, in Ptolemy's catalogue, which Bayer has denoted by the letter k, and which 

 is presumed to be the same as that which has been designated by Lacaille as y Gruis. As 

 there is some ambiguity however in the position of this star in Bayer's map, it is here assumed 

 (like some other stars already mentioned) as common to both constellations, in order to adjust 

 this discordance ; and, in the present catalogue, Lacaille's designation of y Grids is retained, 

 on account of its forming the principal object in the head of that constellation." 



