Dec. 1, 1885.] 



♦ KNOWLEDGE 



47 



nebulie are part of our galactic system. One may com- 

 pare the case to what might be observed bj- any one 

 looking at our solar system from some vast distance, but 

 with power to see its smallest individual components. 

 Such an observer would tind the asteroids numerous 

 between the regions where the two families of planets — 

 the giant planets and the terrestrial jilanets — pursue 

 their separate careers. If he failed to notice how 

 precisely the ring of asteroids appeared to occupy the 

 mid-zone between these planetary families, he might very 

 well fall into the mistake of supposincf that the ring of 

 asteroids was a remoter family of planets, severallj- 

 having (on the average) as great a bulk as the terrestrial 

 planets, or even as their giant brethren. Nay we can 

 imagine him falling into a more complicated mistake, 

 and setting the terrestrial planets farther away than the 

 giant planets, and the asteroidal family much farther 

 away still. But if, continuing his observations, he noted 

 the exact agreement of the asteroidal zone with the space 

 where separate large planets were not travelling, and if 

 further he had some idea of the laws of probabilities, he 

 would at once assign to the asteroids their true position 

 as parts of the planetary system. So, as Mr. Spencer 

 long since pointed out,* we must unhesitatingly regard 

 the nebula' as parts of that system to which the sepHrate 

 stars belong with whose groupings their own so exactlv 

 fit. 



But precisely as the leaves and branches of a tree 

 occupy diiierent regions, if we consider the tree in detail, 

 while they occupy the same region if we regard the tree 

 as a whole, so, if there were any part of our galaxy so 

 separate from the rest that we could view it from out- 

 side, we might expect to find stars and star-clouds inter- 

 mixed within it. It so chances that there are two such 

 regions, the Greater and Less Magellanic Clouds. In 

 these we find stars of all orders from the seventh down 

 to irresolvable stellar nebulosity, — just as we should in 

 the richer regions of the Milky Way, if these were 

 removed so far away that the brightest stars in them 

 were reduced to the seventh magnitude. And precisely 

 as that would bring the star-clouds (now, from oiir inner 

 standpoint, seen away from the galaxy) into the same 

 field of view with its streams and branches, so do we 

 find the Magellanic Clouds containing all orders of nebula;. 



While then I would regard the more diffuse parts of 

 the Milkj- Way as belonging to portions of our stellar 

 system in the midst of which our solar system lies, and the 

 better defined parts in the southern heavens as portions 

 farther away, I regard the Magellanic Clouds as portions 

 much farther away still. 



So much I have long maintained. But now the appear- 

 ance of a new star in the great Andromeda Nebula 

 emphasises ths evidence already suflicient to show the 

 general nature of our galaxy. On May 9th, 1860, before 

 astronomers had begun to study nebula:' and stars with 

 the spectroscope, a star of the seventh magnitude shone 

 out in the midst of a nebula in the Scorpion, or rather in 

 place of it, for while the star was shining the nebula was 

 unseen. As the star faded away the nebula (80 Messier, 

 almost midway between o and p) a star-cluster, one of 

 those referred to by Sir John Herschel in his letter to me 

 (see last number) resumed its normal appearance. In 1873, 

 a star appeared in the midst of a planttanj nebula — before 



* In 186D in my •' Xew Theorj' of the Universe " I pointed to the 

 same evidence, not knowing that Mr. Spencer had earlier called 

 attention to it. This I mention, partly for the purpose of handing 

 over to the proper person such credit as may be due for the recog- 

 nition of the force of this piece of evidence, partly to show that the 

 force of the evidence once noted is unmistakable. 



unknown — in Cygntis ; and again as the star died otit the 

 nebttla became visible. In the great Argo Nebula a star 

 nomiuallv of the seventh magnitude shone out as a star 

 of the lirst magnitude, and then faded out of view, the 

 nebula becoming apparently more conspictious as the star 

 faded. Of all the so-called new stars which have been 

 observed since the matter could be tested, only one, the 

 new star in the Northern Crown, was not associated with 

 any recognisable nebula. So again every new star, except 

 the last-mentioned, has appeared close bj- the Milky Way, 

 and generalh- on its borders— and even the star in the 

 Northern Crown lies in a region towards which milky 

 star-streams extend. 



This being so, I imagine no one with any power of 

 forming a philosophic opinion, doubted the physical asso- 

 ciation between the new star in Andromeda, and the 

 marvellous nebula in whose midst it has appeared. Even 

 those who thus doubted, had their dotibts removed, — at 

 least I should imagine so (speaking always of persons 

 possessing reasoning power) when it was found that in 

 the main the spectrum of the new star was the same as 

 the highly-characteristic spectrum of the nebula. (There 

 was no fear of confounding the two spectra together.) 



This being so we have every reason for inferring that 

 the new star appeared in a part of the galaxy which is 

 probabl}' the nearest to our solar system. In this part 

 from Orion to Cepheus, the five nebula' visible to the 

 naked eye are all found. Two are shown in the illustra- 

 tive maps, and these objects are probably as near to us 

 as the lucid stars are (i.e. those visible to the eye), on the 

 average, if not nearer. 



The picture of the Andromeda Nebuki is from the view 

 made with the Harvard telescope by Trouvelot. The 

 new star is not quite central, but it is in the very heart 

 of the nuclear region of the nebula. 



AS a memorial lo the late Sir Titus Salt, and in recognition of his 

 benefactions to Saltaire, the Governors of the .Salt Schools have 

 decided to build a new Science and Art School, costing about 

 ifi.OOO. The building will be completely finished by May 15, on 

 which day will be opened an important Exhibition on the lines of 

 the late International Inventions Exhibition. 



"So one," says Buckle, "can have a firm grasp of any science, if, 

 by confining himself to it, he shuts out the light of analogy. He 

 inav, no doubt, work at the details of his subject ; he may be useful 

 in ••idding to its facts : he will never be able to add to its philosophy. 

 For the philosophy of every department depends on its connection 

 with other departments, and must therefore be sought at their points 

 of contact. It must be looked for in the place where they touch 

 and coalesce— it lies, not in the centre of each science, but on the 

 confines and margin." 



MoDEBATE Drinking.— It is high time, says the Lancet, to 

 define what moderate drinking is not. It is not drinking in pubUc- 

 houses : it is not drinking on the sly : it is not drinking early in the 

 day : it is not drinking by itself at other than meal-times ; it is_ not 

 drinking to procure sleep" or to relieve pain. All men, and especially 

 all women, who do such things are not moderate drinkers, and had 

 better beware. A moderate drinker takes a very limited quantity 

 once or at most twice a day, with food, such a quantity as does not 

 make him stupid or even sleepy, such as leaves him cool and unex- 

 cited. The moderate drinker takes the lightest forms of alcohol, and 

 takes even these with care. He knows the power of alcohol to pro- 

 duce disease, and is on the look-out for any indication of harm or 

 excess. We do not think it proved that such persons become 

 drunkards. It is terrible, however, to see how soon a drunkard is 

 made bv thoughtless drinking, and how complete is his physical 

 destruction often before he, or perhaps she, comes under medical 

 notice. Jaundice, or dropsy, or albuminuria, or delirium tremens, 

 may have been reached before friends, unwilling to admit what they 

 fear, will send for the medical adviser and make a clean breast of 

 it. Alongside all the teetotali.sm that exists, there is still an appalhng 

 amount of tippling which docs not distinctly intoxicate, but satu- 

 rates the principal organs, and destroys them more quickly than an 

 occasional debauch. " Cut, as we have said, thjs is not moderate 

 drinking— it is mortal drinking. 



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