THE GREAT NEBULA IN ORION. 567 



discovery of a starless nebula, or to acknowledge that lie had himself 

 fallen iuto an error on the subject of nebuloe, prevented Galileo from 

 speaking about the great nebula in Orion, we should be compelled to 

 form but a low opinion of his honesty. It happens too frequently 

 that 



" The man of science himself is fonder of glory, and vain 

 An eye well-practised in Nature, a spirit bounded and poor." 



That Hevelius, the " star-cataloguer," should have failed to detect 

 the Orion nebula is far less remarkable; for Hevelius objected to the 

 use of telescopes in the work of cataloguing stars. He determined 

 the position of each star by looking at the star through minute holes 

 or pinnules, at the ends of a long rod attached to an instrument re- 

 sembling the quadrant. 



The actual discoverer of the great nebula was Huyghens, in 1656. 

 The description he gives of the discovery is so animated and interest- 

 ing that we shall translate it at length. He says : 



" While I was observing the variable belts of Jupiter, a dark band 

 across the centre of Mars, and some indistinct phenomena on his disk, 

 I detected among the fixed stars an appearance resembling nothing 

 which had ever been seen before, so far as I am aware. This phe- 

 nomenon can only be seen with large telescopes such as I myself make 

 use of. Astronomers reckon that there are three stars in the sword of 

 Orion, which lie very close to each other. But, as I was looking, in 

 the year 1656, through my 23-feet telescope, at the middle of the 

 sword, I saw, in place of one star, no less than twelve stars, which, in- 

 deed, is no unusual occurrence with powerful telescopes. Three of 

 these stars seemed to be almost in contact, and with these were four 

 others which shone as through a haze, so that the space around shone 

 much more brightly than the rest of the sky. And, as the heavens 

 were serene and appeared very dark, there seemed to be a gap in this 

 part, through which a view was disclosed of brighter heavens beyond. 

 All this I have continued to see up to the present time " (the work in 

 which these remarks apfpear, the " Systema Saturnium," was published 

 in 1659), " so that this singular object, whatever it is, may be inferred 

 to remain constantly in that part of the sky. I certainly have never 

 seen any thing resembling it in any other of the fixed stars. For 

 other objects once thought to be nebulous, and the Milky- Way itself, 

 show no mistiness when looked at through telescopes, nor are they any 

 thing but congeries of stars thickly clustered together." 



Huyghens does not seem to have noticed that the space between 

 the three stars he described as close together is perfectly free from 

 nebulous light, insomuch that, if the nebula itself is rightly compared 

 to a gap in the darker heavens, this spot resembles a gap within the 

 nebula. And, indeed, it is not uninteresting to notice how compara- 

 tively inefficient was Huyghens's telescope, though it was nearly eight 

 yards in focal length. A good achromatic telescope two feet long 



