[harvey] PYTHAGORAS AND HIS PHILOSOPHY 259 



We believe our universe was once a nebula.^ There is even now 

 what may be called " an invisible veil of nebula over the whole sky." 

 (Prof. -Tiurner, Modern astronomy). In parts thereof the phoitograiphic 

 plate reveals to us enormous aggregations of feebly luminous gas. The 

 stars of the Pleiades are enwrapped in mists which extend in wisps 

 from one to another; the great Dumb-bell nebula has a broad ring 

 of nebulosity surrounding its globular mass; Orion has in his sword 

 a nebula which to the eye is huge, but the sensitised plate, by long 

 exposure, shows thé whole giant constellation to be wreathed in filmy 

 ribbons and scarfs. We think the stars were formed by the concentration 

 of nehulous matter into spherical forms by the attraction of gravita- 

 tion, but of the nature and cause of this force we know nothing yet, 

 though we have learned that it acts in the same way throughout the 

 universe. This so-called universe may be limited, and is possibly 

 globular, but we suppose it would require at least 10,000 years for light, 

 which travels nearly 200,000 miles a second, to traverse the assemblage 

 of stars it contains. While stars are being formed, some of the coal- 

 escing matter is either left behind or thrown off by the rotation of the 

 principal body and forms planets. 



We believe the stars are all in movement, possibly around their 

 common centre of gravity, and that our sun, which is one of them, is 

 rnsjiing towards a point in the heavens where the others seem to be 

 opening out before him, while behind him they are closing in. We 

 see with our telescopes, within many nebulœ, luminous patches which 

 we think are stars in process of formation, and we have observed many 

 stars kindle where previously there were none to be seen. We have 

 ascertained that they are composed of similar materials to those we 

 have under our feet, and we have sorted them out into classes according 

 tc their different luminosities, which are thought to indicate their 

 ■various stages of development. We think that as one star differs from 

 another in glory, some emitting more light than others, so there are 

 probably multitudes of dark stars, and that all stars have a regulated 

 life-history of birth, growth, decay and death. Outside our universe 

 of stars, in which the sun is not central, there may be others, also 

 globular, and so on, throughout space, ad infinitum. The universe, 

 we think, is bathed in ether, of the nature of which we as yet know 

 very little. Ether, matter, electricity, seem to merge, and to be the 

 Ur-stoff or protyle from which atoms grow. 



"• Herschell used to call it Fire-Mist; it was then thought to be attenu- 

 ated hydrogen. It is material, for it gives to the spectroscope a peculiar 

 green line (nebulium) and it is now thought by Sir Wm. Crookes to be matter 

 In a fourth state, that of radiance. 



