150 LUSM03. 



tlie apex of" the shoot of a bambusa, and at another on thft 

 rapidly-growing stem of an American aloe [Agave Ame?'icana), 

 precisely as the astronomer places his cross of net-work against 

 a culminating star. In the collective life of physical nature, 

 in the organic as in the sidereal world, all things that have 

 Deen, that are, and will be, are alike dependent on motion. 



The breaking up of the Milky Way, of which I have just 

 spoken, requires special notice. William Herschel, our safe 

 and admirable guide to this portion of the regions of space, 

 has discovered by his star-guagings that the telescopic breadth 

 of the Milky Way extends from six to seven degrees beyond 

 what is indicated by our astronomical maps and by the extent 

 of the sidereal radiance visible to the naked eye.* The two 

 brilliant nodes in which the branches of the zone unite, in the 

 region of Cepheus and Cassiopeia, and in the vicinity of Scor- 

 pio and Sagittarius, appear to exercise a powerful attraction 

 on the contiguous stars ; in the most brilliant part, however, 

 between fi and y Cygni, one half of the 330,000 stars that 

 have been discovered in a breadth of 5^ are directed toward 

 one side, and the remainder to the other. It is in this part 

 that Herschel supposes the layer to be broken up.f The num- 

 ber of telescopic stars in the Milky Way uninterrupted by any 

 nebulee is estimated at 18 millions. In order, I will not say, 

 to realize the greatness of this number, but, at any rate, to 

 compare it with something analogous, I will call attention to 

 the fact that there are not in the whole heavens more than 

 about 8000 stars, between the first and the sixth magnitudes, 

 visible to the naked eye. The barren astonishment excited 

 by numbers and dimensions in space, when not considered 

 with reference to applications engaging the mental and per- 

 ceptive powers of man, is awakened in both extremes of the 

 universe, in the celestial bodies as in the minutest animal- 

 cules. $ A cubic inch of the polishing slate of Bilin contains, 

 according to Ehrenberg, 40,000 millions of the silicious shells 

 of Galionellse. 



The stellar Milky Way, in the region of which, according to 

 Argelander's admirable observations, the brightest stars of the 

 firmament appear to be congregated, is almost at right angles 



* Sir William Herschel, in the Philos. Transact, for 1817, Part ii 

 p. 328. t Arago, iu the Annnaire, 1842, p. 459. 



t Sir John Herschel, in a letter from Feldhuysen, dated Jan. 13th, 

 1836. Nicholl, Architecture of the Heavens, 1838, p. 22. (See, also, 

 Bome separate notices by Sir William Herschel on the starless space 

 which separates ns by a great distance from the Milky Way, in the 

 Philos. Transact, for 1817, ''art ii., p. 328.) 



