^■OVE^tBER. 1910. 



KNOWLEDGE. 



429 



was adopted by Baily in the British Association 

 Catalogue of <VJJ7 Stars, and in the Catalogue of 

 9766 Southern Stars formed from Lacaille"s zones, 

 and it has been generalK- adopted in recent Southern 

 Catalogues. It has, therefore, the authorit\- of more 

 than 30 [now 60] years" extensive use in its favour. 

 It appears to me very doubtful whether all the 

 changes introduced b\- Herschel and Bail\- were 

 necessary or, indeed, desirable, but less confusion is 

 probably now caused bv the adoption of these 

 changes than by attempts to revert more closely to 

 Lacaille's original nomenclature." 



Stone unfolded the same doctrine in a letter \s hich 

 he wrote to me under the date of September 8th, 

 1880. I had consulted him as to the nomenclature 

 of the Southern constellations, intending to follow in 

 the new edition of Admiral Smyth's Cycle of 

 Celestial Objects, as well as I might be able to do. 

 anv advice which he might give me. Stone said : — 

 " I have practically followed the B.A.C. in my 

 nomenclature. Bailv followed Herschel's advice 

 after Herschel found that no sweeping changes in 

 Lacaille's svstem would be acceptable."' Stone in 

 effect said '' Meddle not with him that is given to 

 change."" and as this conservative idea commended 

 itself to me I acted upon it. Some years afterwards 

 Stone, after returning from the Cape of Good Hope, 

 became Radcliffe Observer at Oxford. In the 

 Preface to the Radcliffe Catalogue of 6424 Stars 

 edited bv him, he terselv summed up his treatment 

 of the subject in the following v.ords: "" In the 

 division of the sk\- into constellations the nomen- 

 clature and boundaries adopted by Francis Baily, 

 with the sanction of Sir John Herschel, have been 

 generally followed, but no especial importance has 

 been attached to this part of the work."" 



The principles which Sir J. Herschel laid down 

 are stated bv him under seven heads. As the text of 

 them is not generallv accessible, though evervbodv 

 now-a-days is dependent on them (Gould"s organic 

 changes having been very generallv repudiated), it 

 will be well to set them out because the\' furnish a 

 useful clue to the profitable studv of the constella- 

 tions speciallv affected, including particularlv the 

 troublesome constellation Argo. 



The following is an authoritative statement * of 

 them : — 



■■ ( 1 1 That all the Constellations adopted bv 

 Lacaille be retained, and his arrangement of the 

 Stars preserved : subject, how ever, to certain altera- 

 tions hereafter specified. 



'■ (2) That all the Stars having a doubtful location, 

 such as those which Lacaille (after the manner of 

 Ptolemv) has considered as afiopfjiwroi (unformed), 

 be included within the boundaries of either one or 

 other of the contiguous constellations, so as to 

 preserve a regularity of outline and nomenclature. 



'■ (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 constellation, 

 in which they are registered, to admit of an uniform 

 contour of the lines ; secondly, such Stars as have 

 been previously observed by Ptolemy or Flamsteed, 

 and b\- them located in other constellations, or which 

 interlace, and are confusedly mixed with such 

 previously observed stars : thirdly, the four 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 constellations less circuitous. 



■■ i4i That the letters selected b\' Lacaille be 

 adopted in preference to those introduced bv Baver 

 in Argo, Centaurus. .\ra and Lupus. That the 

 Greek letters (with a few exceptions) be retained 

 only as far as Stars of the 5th magnitude, inclusive. 

 That no Roman letters be at present used, except in 

 the sub-divisions of .\rgo subsequently mentioned. 



"(5) That Argo be divided into four separate 

 constellations, as partly contemplated b\' Lacaille. 

 retaining his designations as Carina, Puppis and 

 \'ela ; and substituting the term Malus for Pyxis 

 Nautica, since it contains four of Ptolem\"s Stars that 

 are placed by him in the mast of the ship. 



" (6) That the original constellation, Argo. on 

 account of its great magnitude and the sub-divisions 

 here proposed, be carefulh- revised in respect to 

 lettering, in the following manner : first, in t)rder to 

 preserve the present nomenclature of the principal 

 Stars, all the Stars in Argo (that is. in the general 

 constellation, regarded as including the sub-divisions 

 above mentioned), indicated h\ Greek letters by 

 Lacaille, be retained, with their present lettering, 

 under the general name, .\rgo ; secondly, all the 

 remaining Stars to be designated bv that portion of 

 the ship in which thev occur, such as Carina, 

 Puppis, \'ela and Malus, and to be indicated b\- the 

 Roman letters adopted by Lacaille, as far as the 5th 

 magnitude inclusive. And no two Stars, far distant 

 from each other in the same sub-division, to be 

 indicated by the same letter : but in cases of conflict, 

 the greater magnitude to be preferred : and when 

 they are equal the preceding Star to be fixed upon. 



"(7) That the constellations which Lacaille has 

 designated b\' two words be e.xpressed bv onlv one of 

 such words. Thus, it is proposed that the several 

 constellations indicated by Lacaille as Apparatus 

 Sculptoris. Mons Mensae, Caelum Scalptorium, 

 Equulius Pictoris, Piscis \olans, and Antlia 

 Pneumatica. be called by the respective titles of 

 Sculptor, Mensa, Caelum, Pictor, Volans and Antlia ; 

 contractions which have on some occasions been 

 partially used by Lacaille himself, and are veoi- 

 convenient in a registry' of Stars."" 



' I call this ■" authoritative " because it appears in the Preface to the British Association Catalogue as given by Baily. 

 apparently on behalf of Herschel ; but it is not expressly stated to be in Herschel's own words, though I infer that the words 



are Herschel's. 



