A CHART OF CIRCUMPOLAR STARS. 275 



A CHART OF CIRCUMPOLAR STARS. 



By H. C. Russell, b.a., c.m.g., f.r.s. 

 [With Plate XL.] 



[Read before the Royal Society of N. 8. Wales, July 4, 1894.~] 



Circumstances have frequently brought under my notice the 

 difficulties felt by amateurs in finding, on the ordinary star charts, 

 the several stars which they may see in the heavens, and hence I 

 have designed a chart of southern circumpolar stars, which I 

 thought would be more convenient and easy for them to use than 

 the star charts previously published. I have also introduced some 

 results from my own work which seemed desirable additions to the 

 information usually given ; these will be referred to later. 



For the ordinary amateur's use, too much has been attempted 

 on the best star charts. He wants to recognise the visible 

 stars in their relative positions, and not to have the chart 

 crowded by details which only come to him in later studies. The 

 smallest star put in is of 6-5 magnitude, and should be visible to 

 good eyes on a fine night. It is possible that some stars are 

 visible which are not in the catalogues and which will therefore 

 not be found here. Great care was taken in selecting sizes for 

 the star spots which would make it easy for the eye to pick up 

 the bright stars, and in order still further to aid in this ease in 

 using the chart, each star to the fifth magnitude inclusive has 

 projecting rectangular bars, the number of which at once decides 

 the magnitude, and all stars of 5*5 to 6*5 magnitude are simply 

 round spots. The abreviations used are all shown on the chart 

 for easy reference, and on the outer rim a series of dates by which 

 to set the chart. If any date is set vertically over the centre of 

 the chart, then at 8 p.m. of that date, the stars bear the same 

 relation to the horizon and the points of the compass (when look- 

 ing south), as they do when one looks at the stars themselves. 



