150' COSM(.S. 



ually look throngli as into free space. " It leads us," say.< 

 Sir John Ilersclicl, "irresistibly to the conclusion that in 

 these r3gions we see fairly through the starry stratum. "=* 

 Tn other regions we see, as it were, through openings and 

 fissures, remote world-islands, or outbranching portions of the 

 annular si^stem ; in other parts, again, the Milky Way has 

 hitherto heen fathoinless, even with the forty-feet telescope. t 

 Investigations on the different intensity of light in the Milky 

 Way, as well as on the magnitudes of the stars, which regu- 

 larly increase in number from the galactic poles to the circle 

 itself (an increase especially observable for 30° on either side 

 of the Milky Way in stars below the eleventh magnitude,t 

 and therefore in -j-fths of all the stars), have led the most 

 recent investigator of the southern hemisphere to remarkable 

 viev/s and probable results in reference to the form of the 

 galactic annular system, and what has been boldly called 

 the sun's 2^lace in the world-island to which this annular 

 system belongs. The place assigned to the sun is eccentric, 

 and probably near a point where the stratum bifurcates or 

 spreads itself out into two sheets, § in one of those desert re- 

 gions lying nearer to the Southern Cross than to the oppo- 

 site node of the Milky AVay.il "The depth at which our 

 system is plunged in the sidereal stratum constituting the 

 galaxy, reckoning from the southern surface or limit of that 



* Outlines, p. 536, 537, where we find the following words on the 

 same subject : " In such cases it is equally impossible not to perceive 

 that we are looking through a sheet of stars nearly of a size, and cf 

 no great thickness compared with the distance wliich separates them 

 from us." 



t Struve, Etudes StelL, p. 63. Sometimes the largest instruments 

 reach a portion of the heavens, in which the existence of a stany stra^ 

 turn, shining at a remote distance, is only announced by " a uniform 

 dotting or stippling of the field of view." See, in Observations at the 

 Cape, p. 390, the section " On some indications of very remote telo. 

 scopic branches of the Milky Way, or of an independent sidereal sys- 

 tem or systems beai'ing a resemblance to such branches." 



t Observations at the Cape, $ 314. 



$ Sir WiUiam Herschel, in the Philos. Transact, for 1785, p. 21 ; Sir 

 John Ilerschel, Observations at the Cape, ^ 293. Compare also Struve, 

 Dcscr. de V Ouscrvatoire de Poulkova, 1845, p. 267-271. 



II "I think," says Sir .lohn Ilei-schel, "it is impossible to view this 

 splendid zone fi'om a Centauri to the Cross without an impression 

 amounting almost to conviction that the Milky Way is not a mere stra- 

 tum, but annular; or, at least, that our system is placed within one of 

 the poorer or almost vacant parts of its general mass, and that eccen- 

 trically, so as to be much nearer to the region about the Cross than te 

 that diametrically opposite to it." (Mary Somerville, On the Conner 

 **on of the Physical Sciences, 1846, p. 419.) 



