58 The Great Nebula in Orion. 



pairs, triplets, and more complicated arrangements will be 

 found. Two beautiful little triangles will be sure to attract 

 notice. 



DOUBLE STAR. 



We shall meet with a beautiful object well worthy of being 

 added to our former list by looking first for a considerable 3 

 mag. star, y Gciautoriuu, which lies between Pollux and Betel- 

 geux, but nearer to the latter. A little s f from this star we 

 shall notice two of the 4 and 5 mag., very near together, g 1 and 

 £ 2 , and s again from these, a little _p, another : this is the star 

 of which we are in quest. 



120. 15 Monocerotis. 2"*5. 206 c,, 2. 6 and 9|, greenish and 

 pale grey. This fine and easy object is converted into a triple 

 group by the addition of a minute comes, which Smyth calls 

 blue, at 15" and 15°. He assigns to it only 15 mag., but I 

 have found it more visible than I should have expected, being 

 steadily seen with 5£ inches and a high power. Another still 

 more minute attendant, unnoticed by Smyth, lies at a greater 

 distance in the n p quadrant. Just s of the principal star, 

 three other small pairs form an irregular transverse line across 

 the field, and further in the same direction we shall find a fine 

 group, requiring a low power. Many parts of ■ this galaxy 

 region are very glorious. 



THE GREAT NEBULA IN ORION. 



So lengthened a description of this nebula was given upon 

 a former occasion, that some explanation seems requisite to 

 account for its re-introduction at the present time. It is simply 

 the result of a closer acquaintance with this great marvel of 

 the heavens. A more careful telescopic examination of it than 

 I had ever previously attempted, combined with a more ex- 

 tended comparison of the principal drawings of our great 

 observers, has led me to think it an object worthy of much 

 more, even at the hands of amateurs, than a passing gaze of 

 wonder, and capable of repaying their diligent study and 

 careful delineation. The discrepancies with regard more 

 especially to the internal distribution of the luminous haze, as 

 represented by our best observers, ;md by means of the finest 

 instruments, are so obvious, Hint 1 feel less disposed than I 

 should otherwise have done, fco reject my own results, or think 

 lightly of those of others, my fellow students, on the mere 

 ground of their differing iu some respects from all that lias 

 preceded them. Where (lie highest authorities differ, there is 

 room lor every man's independent workj and in such a case 

 the aspirin;'- sentiment of Tycho Brahe may lie applied without 

 diminution of the veneration with which we ought always to 

 regard OUT masters in science : — 



"Anne i(a decet non scrvilitcr addictos aliorum prolatis, ut nihil in his ipsimet 

 experiamur?" 



