Notices respecting Neiv Books. 67 



painter. But as corrective of that picture, we can fortunately 

 point attention to the author's own view of the Aurora as seen in 

 Kyle Akin, Isle of Skye, in 1874. The quiet of the scene there, 

 the grand symmetry of the chief arrangements in luminous arch 

 behind arch of impalpable light, the mysterious extra darkness 

 below, and the black clouds in front, are what, we well know, do 

 often characterize the Aurora in that part of the world, and speak 

 so solemnly of one of the greater mysteries of nature, extending 

 from here into starry space, and thence presenting to man a symbol 

 of the still unknown, unsolved enigmas of the universe of earth and 

 heaven. 



Part the Second deals with the spectroscopic g of the Aurora, and 

 is very full with all that has been, or may be, done in the way of 

 spectroscopic observation, and the best instrumental means for 

 accomplishing it. 



Herein it may just happen that some persons will be moved to 

 complain of the rather fragmentary character of much of the reading; 

 repeated and intensified, too, as that defect is in some of the plates, 

 where spectra appear longways, crossways, on scales of various 

 length, and in bits and corners sometimes of plates already occupied 

 with spectroscopes, gas-vacuum tubes, micrometers, &c. Yet that 

 is really one of the merits of the book when fully considered ; for 

 in the present backward and uncertain state of Aurora-theory it 

 would never do to have too much organizing, cutting, trimming, 

 and reducing to some one man's Procrustean ideas alone, to gain 

 mere symmetry of literary work, seeing that future progress may 

 show some day that, in so doing, certain of the most important 

 points of observation have been left out. 



Mr. Capron therefore wisely gives us now every thing he can lay 

 hands on, packing it always into the most practicable shape for 

 printer and engraver, author and reader combined. And to judge 

 how important it was that he should do so, we have only to refer 

 back to seven years since, when some few spectroscopists of Aurora, 

 or what they thought was such, had arrived at a most simple expla- 

 nation of the whole affair — grand certainly, but baldly insipid, — 

 and had very nearly induced the world to rest from its exertions, 

 under the idea that there was nothing more to be discovered. 

 At that period, so soon after the brilliant discoveries of the 

 greater men, when a single glance almost in a spectroscope had 

 settled the gaseous nature of nebula versus the solid or fluid state 

 of stars, and had detected by a line whether, say, hydrogen, or iron, 

 or calcium, or any other particular chemical element existed in sun, 

 or star, or any burning flame anywhere upon this earth far or near, 

 it was certainly expected that the auroral light, so close to us deni- 

 zens of the earth as to be generally within ninety miles of its sur- 

 face, would soon fall an easy prize to the wonder-working modern 

 power of prismatic vision through a narrow slit. 



Moreover one distinguishing and all-important bright line had 

 been found in the citron or yellow- green region of the Aurora's 



F 2 



