422 



KNOWLEDGE. 



November, 1913. 



it is intended, shall run on after Z Z, with the letters 

 A A, A B, AC, and so on, prefixed to the name 

 of the constellation. If this part of the dual 

 notation be not continued beyond A Q, B Q, and so on, 

 there will be provision for one hundred and thirty-six 

 additional variable stars in each constellation. If 

 it be continued, as is being done in Hartwig's 

 Ast. Gesell. annual catalogues, from A A to A Z, as 

 far as Q Q to Q Z (always omitting J), then there will 

 be provision for two hundred and eighty stars, besides 

 the fifty-four from R to Z Z for each constellation. 



In 1909 there were eighty-six constellations in 

 which one or more variable stars had been dis- 

 covered. The state of this lettered nomenclature 

 in 1909 was that in the constellation of Scutum 

 there were nine lettered variable stars and thirty-one 

 waiting for letters, in Sagittarius twenty-seven 

 lettered stars and seventy-four waiting, in Scorpio 

 twenty-five lettered stars and eighty-four waiting, 

 and in Orion there were nine lettered stars and one 

 hundred and twenty - five waiting for letters of 

 identification. In 1912 the constellations of 

 Cygnus, Scorpio, Sagittarius, Centaurus, Carina, 

 Aquarius, Aquila, Hercules, Andromeda, and Draco 

 had almost exhausted the R to Z Z section of the 

 alphabet ; in fact, A K was reached for Scorpio, AO 

 for Sagittarius, while for Cygnus the alphabet with 

 dual notation had been passed through once, and 

 A Z reached. For Scorpio there were thirty-nine 

 more lettered variable stars than in 1909, and yet 

 there were forty-five more already discovered and 

 waiting for letters. At the rate at which variable 

 stars are being photographically discovered it will 

 require but two or three years, perhaps, for the 

 whole alphabet to be used up in the dual form. To 

 continue to ring the changes with triples would be 

 cumbersome. The single or double letter form with 

 the figure 3 as an index might be convenient, both 

 for manuscript use and print, as R 8 , S 8 Z, or A 3 Q ; 

 but any extension of the scheme by mere variation 

 of printers' type — as has been suggested — would be 

 extremely inconvenient, and a source of many errors. 



We shall now return to the historical side of the 

 subject and resume the thread of Argelander's 

 Catalogue of 18 variable stars published in 1844. 



Though the lettered nomenclature had been in 

 use for some years, Argelander had given no very 

 definite account of the scheme until that which 

 appeared in the Astronomische Nachrichten, No. 959, 

 1855, May 3rd ; this explanation may be given best 

 in his own words : — 



" Mit R bezeichne ich den Stern in der Jungfrau, dessen 

 periodische Veranderlichkeit Harding im Tahre 1809 entdeckt 

 hat, und dessen Position fur 1855 ist: 12 s 31 m 9 s + 7° 47'- 3. 

 Dass ich einen nicht bei Bayer vorkommenden Stern mit 

 einem Buchstaben bezeichne, wird mir hoffentlich nicht 

 verdacht werden. Die veranderlichen Stern haben bei ihrer 

 Merkwiirdigkeit wohl ein Anrecht auf eine solche Auszeich- 

 nung, die zur Bequemlichkeit der Nachweisung bei so oft 

 erwahnten Sternen fast unentbehrlich ist. Um aber eine 

 Verwechselung mit den Ba^er'schen Buchstaben moglichst 

 zu vermeiden, habe ich die letzten des Alphabets gewahlt, und 

 sie dem grossen Alphabete entnommen. Nur im Hercules 



gehen die lateinischen Buchstaben bei Bayer bis z, im Stier 

 bis t, in der Jungfrau bis q, im Lowen, Orion und Schwan 

 bis p ; im letztern Sternbilde ist dies ein grosser Buchstabe. 

 Bayer kennt sonst fur seine Bezeichnungen in den Stern- 

 bildern von den grossen Buchstaben nur das A ; die andern 

 grossen Buchstaben, die auf seinen Charten vorkommen, 

 weisen entweder auf hellere Sterne benachbarter Sternbilder 

 hin oder auf ausgezeichnete Puncte der Himmelskugel. Nur 

 bei dem bekannten neuen Sterne vom Jahre 1600 macht er 

 eine Ausnahme, indem er ihn mit P bezeichnet ; er sagt : ' P 

 tertii fulgensstella, anno MDC primum conspecta et observata, 

 omnium ferme tacito consensu pro novo phaenomene recepta, 

 eundem adhuc hodie retinet situm e.q.s.' Ich kbnnte somit 

 Bayer als meiner Vorganger bei dieser Auszeichnung der 

 veranderlichen Sterne citiren ; indess glaube ich, dass dieser 

 Astronom daran nicht gedacht hat, sondern den Stern in seiner 

 vor 1600 schon fertigen Charte, vielleicht erst auf der 

 Kupferplatte, nachgetragen, und desshalb die Ordnung nicht 

 unterbrechen wollte ; er hatte ihn sonst nach seiner Methode 

 mit 7, 7 mit S bezeichnen miissen, u-s-w, also waren alle 

 folgenden Sterne geandert worden." 



The nomenclature proposed and used by Argelander 

 was generally adopted. Here is an example by 

 Dr. R. Luther (Bilk) in Ast. Nach. No. 996 (1855, 

 November 29th) : " welcher nach dem Argeland'- 

 schen Vorschlage (in No. 959 der Ast. Nach.) 

 T Piscium bezeichnet werden moge." 



Argelander's Catalogue was followed by Norman 

 Pogson's pioneer work at the Radcliffe Observatory, 

 and he published a catalogue of 53 stars in 1854, 

 using Argelander's notation ; G. F. Chambers, 

 who is still living, published a list of 123 variable 

 stars in the Astronomical Register, II, 194, in 1864, 

 August ; this was reprinted in the Astronomische 

 Nachrichten in Band LXIII, page 117; a revised 

 form also appeared in the Monthly Notices of the 

 Royal Astronomical Society vol. XXV, page 208 

 (1865, May), and in later years catalogues of 235 

 variable stars, 126 probably variable, and 500 red or 

 orange stars in his Handbook of Astronomy. In these 

 catalogues he was helped by J. Baxendell, G. Knott, 

 F. Brodie, and J. E. Gore. In 1865 and 1875 

 Schonfeld published catalogues. The number then 

 given was 143 stars: to this number 48 variable and 

 77 suspected variable stars were added at Harvard 

 Observatory in 1883, and further lists were 

 published from Harvard in the Proceedings of the 

 American Academy of Sciences, vols. XIX-XXII. 

 In 1888 an Index to observations of variable star 

 (published) observations was given in the Annals of 

 the Astronomical Observatory of Harvard College, 

 vol. XVIII, No. VIII: in this 225 stars are given 

 and the records of 125,720 observations made from 

 1838-1888 are indicated. 



Chandler published in The Astronomical Journal, 

 vol. VIII, 81 (1888), a catalogue of 225 variable stars, 

 with their elements, and a great deal of other 

 information ; a second edition, containing 260 stars, 

 was published in The Astronomical Journal, vol. XIII, 

 page 89 (1893) ; and a third and last edition, record- 

 ing 393 stars, was published in The Astronomical 

 Journal, vol. XVI, page 145 (1896). Soon after 

 this Roberts published a catalogue of 94 stars south 

 of —23° Dec, a portion of the sky previously much 

 neglected. 



