Astronomical Society. 533 



centuries. Thus Siriits is described in all the original documents 

 that I have seen, as vnvKipfyos, siihrvffa, reddish ; whereas, at the pre- 

 sent da}', it is remarkable for its freedom from all colour. Now, this 

 is a point on which Ptolemj'^ could not well be mistaken. Again, a 

 star of the fourth magnitude (the seventeenth in the constellation of 

 Eridanus) is clearly laid down by Ptolemy, but cannot now be found ; 

 and there are some others, of smaller magnitude, that cannot be 

 identified, according to the positions given in the present editions of 

 the catalogue. But whether these bodies have vanished wholly from 

 our sight, or have been erroneously copied from the original observa- 

 tions, can only be satisfactorily explained (if, indeed, they ever can 

 be) by reference to other authorities. It is needless, however, to 

 dwell further on so obvious a principle. 



I had taken the liberty of suggesting to the late Professor Rigaud 

 (a name ever dear to the lovers of astronomjr, and more especially 

 to those engaged in historical researches in that science) the ])ro- 

 priety of requesting the University of Oxford to print the catalogue 

 of Ptolemy, from the Greek maimscript in their possession : a re- 

 quest which, I understand, was favourably received. We are all 

 sensible of the obligations under which we lie to the University of 

 Oxford, for its noble and spirited conduct, on former occasions, in 

 publishing the works of some of the best ancient authors on scien- 

 tific subjects, which otherwise might never have seen the light ; and 

 certainly not in so splendid a dress. Witness the works of Euclid, 

 Apollonius, Archimedes, &c. ; and in more recent times, a continu- 

 ance of the same liberal and enlightened course on various occa- 

 sions, in the publication of works that reflect honour and credit on 

 the Universit}', and from which they can never expect to reap any 

 pecuniary benefit. 



Since that application, however, was made, the information re- 

 lative to the additional manuscripts above-mentioned has been ob- 

 tained ; and it may now become a question whether it may not be 

 presumed that a more accurate copy of Ptolemy's catalogue is more 

 likely to be deduced from a careful collation of all the manuscripts 

 within our reach, compared with the several original editions and 

 translations above alluded to, than from the printing and publica- 

 tion of a single Greek manuscript. Should a plan of this kind be 

 attempted, 1 would propose that a few copies of the Basil edition of 

 15;J8 be reprinted (for I fear that the original work is too scarce to 

 be met with in suflicient quantity for this purpose), and distributed 

 amongst those persons who would each undertake to collate such 

 copy with some one or other of the manuscripts in the several 

 archives above-mentioned. This would be no great task or labour 

 to those who feel an interest in the cause, and who arc zealous in 

 the promotion of science. Copies even might be sent abroad, to 

 some of our foreign members, residing in places where originjil 

 manuscripts are known to exist ; and who might thus add to the 

 common stock of information. But, whichever course may be 

 adopted, I trust there is no difference of opinion as to the propriety 

 of taking some steps relative to this matter : and I hope that what 



