STAR-SYSTEMS. NEBULJ2. 185 



While generally exhibiting tolerably defined shapes in the depths of space, some of the 

 more considerable nebulas have a strangely irregular aspect and outline. This is especially 

 the case with reference to the great nebula of Orion, one of the most extraordinary objects 

 in the heavens, for its great extent, inequalities of light and shade, and capricious form. 

 It occurs in the sword-handle of the figure which forms the constellation ; and a good eye 

 may discern it without the assistance of a glass. Huygens was the first to describe this 

 object, though Galileo is said to have observed it through his telescope. " Astronomers," 

 says the former, " place three stars close to each other in the sword of Orion : and, when 

 I viewed the middlemost with a telescope in the year 1656, there appeared, in the place 

 of that one, twelve other stars ; among these, three that almost touch each other, and four 

 more besides, appeared twinkling as through a cloud, so that the space about them seemed 

 much brighter than the rest of the heavens, which appearing wholly blackish, by reason 

 of the fair weather, was seen as through a certain opening, through which one had a free 

 view into another region which was more enlightened. I have frequently observed the 

 same appearance in the same place without any alteration ; so that it is likely that this 

 wonder, whatever it may be in itself, has been there from all time ; but I never took 

 notice of any thing like it among the rest of the fixed stars." This nebula, as discerned 

 by the naked eye, exhibits an indefinite, foggy appearance. It is brighter, more diffuse 

 and strange, when a telescope is used ; but the whole light and power of Herschel's forty- 

 feet reflector could not resolve it into distinct stars. "This highly interesting object," he 

 states, "engaged my attention in the beginning of the year 1774, when, viewing it with a 

 Newtonian reflector, I made a drawing of it ; and, having from time to time reviewed it 

 with my large instruments, it may easily be supposed that it was the very first object to 

 which, in February 1787, I directed my forty-feet telescope. The superior light of this 

 instrument showed it of such a magnitude and brilliancy, that, judging from these circum 

 stances, we can hardly have a doubt of its being the nearest of all the nebulae in the 

 heavens, and, as such, will afford us much valuable information." It seems composed of 

 little flocky masses, or wisps of cloud, adhering to some small stars at its outskirts, and 

 enveloping one with an atmosphere of considerable extent. " I know not," says Sir John 

 Herschel, " how to describe it better than by comparing it to a curdling liquid, or a 

 surface strewed over with flocks of wool, or to the breaking up of a mackerel sky, when 

 the clouds of which it consists begin to assume a cirrous appearance. It is not very 

 unlike the mottling of the sun's disk, only, if I may so express myself, the grain is much 

 coarser, and the intervals darker ; and the flocculi, instead of being generally round, are 

 drawn into little wisps. They present, however, no appearance of being composed of 

 stars ; and their aspect is altogether different from that of the resolvable nebulae. In the 

 latter, we fancy, by glimpses, that we see stars, or that, could we strain our sight a little 

 more, we should see them : but the former suggests no idea of stars, but rather of some 

 thing quite distinct from them." From a comparison of the descriptions and drawings of 

 this object, since the time of Huygens, great alterations might be -inferred. But astrono 

 mical delineation was not then sufficiently advanced to render the diagrams at all satis 

 factory, nor were the instruments sufficiently powerful. The first rigidly accurate 

 representation of it is that by Sir John Herschel, which justifies its familiar name, that of 

 the Fish's Mouth, as it certainly resembles the head and yawning jaws of some monstrous 

 animal, with a kind of proboscis running out from the snout. Its apparent superficial 

 magnitude is rather more than twice that of the moon's disk. The absolute dimensions 

 must be enormous. 



Such, down to a recent date, were the -only ascertained peculiarities of this wondrous 

 mass. From the perfect irresolvableness of this and other nebulae, together with a milky 

 appearance, it was formerly supposed that a distinction must be drawn between them and 



