General Catalogue of Stars for 1860, Fan. 1
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T H E C A P E C A T A L O G U E 1 1 ST ARS 5 9 , D ED UC ED FROM OBSERVATIONS AT T HE R YAL BSERV AT RY C APE O F G O D H PE O O O , O O , 1 8 6 T o 1 8 1 5 6 , RED UC ED TO THE EPOC H UN DER T HE SUPE RIN T EN DRN C R O ? E. S T O N E M . A J , ., ' (L AT E rnww o r mum s couzcz, ca umuncz), ’ HER MAJEST Y S AST RO NO MER AT T HE CAPE. PUBL B HED Br ORD ER OF THE BOARD O F EV OBEDIENC E TO HER M EWS C OMMJND . C APE T OWN O N C O . 8: 0 ST G E O G E S - ST R E E . SA U L SO L O M , 4 9 5 , . R T 1 873 . IN T R O D UC T I O N T O T HE A AL O G U E O F 1 1 5 ST A RS C A PE C T 9 , FO R T HE EPO C H 1 860. O r o f H was a n The Royal bservato y, Cape Good ope, established by in 1 820 O 20. O rder Council, dated , ctober The leading idea was to fi O r H fo r establish a rst class bservato y in the Southern emisphere, work o f a similar character to that o f the Greenwich O bservatory in the Northern Hemisphere. The observations were to be made with ins tru o f a ments the same class, and the results were to be drawn up in the s me f orm , in order that the whole might constitute two corresponding series capable o f comparison in all their parts. No opportunity o f making observations capable o f improving the Theory o f Refraction was to hé neglected . O B s The bservatory uilding were completed the instruments, similar to those at that time in use at Greenwich, mounted ; and observations commenced in 1 829 . But the hand o f death was almost upon the first A . R f 1 8 0 Director. The ssistant, Capt onald, broke down , and le t in 3 ; a nd f Fallows, a ter struggling on , somewhat hopelessly, as best he could o f f 1 8 1 o f with the aid his wi e, died in July, 3 , at the early age 43 , with the expectations which had drawn him to South Africa unfulfilled . Much could not have been done under the circumstances in which Fallows was as . A o f Of placed, and not much w done Catalogue approximate places o f z o f the principal stars, south the enith the Cape, made with small o T rans ac instruments, in Cape Town, was published in the Philos phical o fo r 1 82 f f ti ns 4, and another Catalogue, ormed rom observations made at O 1 82 - 1 8 1 o f R this bservatory 9 3 , appears in the Memoirs the oyal A V o l . XIX 1 8 1 . stronomical Society, , published in 5 It contains the Right Ascensions o f Stars : but o f these only 88 have corresponding observations in North Polar Distance ; a considerable portion o f these places are those o f well- known Stars observed fo r clock error. H Fallows was succeeded by Mr. Thos . enderson , who remained at the Cape a little more than a year ; but that year must ever be a H r memorable one in the annals o f the Cape O bservatory. ende son o f a discovered the sensible parallax Centauri , and determined its amount with an accuracy which has left to his successors little more tha n a it Introduction to the Cape Catalogue v fic n o f his re . He r 1 8 eri atio sult educed and published, in 3 5 , the o f 1 2 o f R declinations 7 Stars, and in in the Memoirs the oyal A R A o f 1 o f a s stronomical Society, the ight scensions 74 the princip l Star , the results o f the observations made by him a nd his assistant at the C ape in 1 83 1 and 1 83 2 . It is impossible to over-estimate the value o f these papers a s affording accurate places o f a lim ited number o f Stars at the epoch but the extent o f the Catalogue is small . Henderson removed all ‘ c s o f his o bsérva tio ns f m O t the re ord ro the bservatory, wi h a view to their s r ubsequent reduction, It is desi able that the original records should be returned fo r preservation at this O bservatory . Mr. Hendersonwa s s b . no w mas o n ucceeded y Mr ( Sir Tho ) Maclear, who arrived at the Cape th o f n 1 8 . m a . a the s Ja uary, 3 4 The observations de by Mr Macle r and his Ass ista nt in the y ear 1 83 4. were published and distributed fo r the use o f A s a o f o bser tronomers, and some dvance was made in the printing the va tio ns 1 8 1 8 6 1 8 r o f r made in 3 5 , 3 , 3 7 but the eductions these yea s were n was . never completed, and the printi g stopped It would appear that attention was cal led o ff from attempts to form a Star Catalogue to the measurem ent o f an arc o f meridian . The field work o f this arc was finished in but it was not until 1 866 that the volumes containing and the results were completely printed published, and Sir Thos . Maclear placed ina position to receive the congratulations o f his contemporaries on the completion o f his work. O f the value o f this work there cannot be two opinions : but it was allowed to disorganiz e the other work o f the O s the b ervatory to such an extent that, when I assumed Directorship ' 1 8 0 f f v s ta fi in 7 , I ound mysel , with a ery limited , unexpectedly confronted with the results o f 3 6 years o f miscellaneous obs erving es o f n in all stag reduction, nothing completed , and nothi g which could be brought forwa rd fo r publication and use without a very considerable expenditure o f time and skilled labour. I fear the cours e pursued o f continuous miscellaneous observing without reduction, has not tended to the advancement o f accurate Astronomy to any extent proportional to the the labour expended upon work, and still required to be expended uponit before the results can be rendered useful . Such observing is rarely conducted in a way to facilitate the s ubsequent reductions or to economiz e l labour in observing. This will be apparent to any one who wi l count ° ° the number o f observations o f Stars between 67 and 1 1 7 North Polar Distance and consider that a Catalogue formed from the results o f other years woul d contain observations o f these Stars to very nearly the same f m relative extent . O f the large number o observations accu ulated f 1 . 1 8 u he re rom 83 4 to 5 5 , with the Transit instr ment and Mural Circles, o f o f the the places o f the Southern Stars, out the reach Northern O e l o f fo r but bservatories, will when reduc d, stil be value proper motions t he immense number o f observatio ns o f well- known Stars made here with of 1 1 5 9 Stars for the epoch 1 860 . iii o l ca no w f r r for the d instruments n , I ear, never epay the labour equired their reduction . The Right Ascensions o f those Stars which have been used fo r clock error ca n do little more than reproduce the assum ed ta bular places em R A n o f r ployed in the reductions, and the ight scensio s other Sta s not further from the Equator than thos e o f the usual clock-star list can never differ much from the results o f the Northern O bservatories . The North Polar Distances o f the same well-observed Stars can now be o f little value. The results are not likely to be compared with those o f the Northern O bservatories fo r a discussion o f the errors o f the refraction tables when results made with more powerful instrumen ts are available. ’ e s stafi I have mad the e remarks , not only in justice to the present , u v and to explain the work pon which they ha e been employed, but because it was these considerations which led me to pass over the earlier observations , and to commence the systematic reductions with the year 1 8 6 was fi use. f 5 , when the Transit Circle rst brought into regular I elt that these reductions coul d not be any longer delayed without the value o f s .