NOTES. 



(1.) See address of Sir John Herschel to the Astronomical Society 

 of London, (1841), in the Transactions of that body, vol. xii. 



(2.) Professor Mosotti, on the Constitution of the Sidereal System, 

 of which the sun forms a part. Lond. Ed. and Dub. Philosophical 

 Magazine. Feb. 1843. 



(3.) Sir John Herschel's Address, ut supra. 



(4.) There is an exception, but doubtless apparent only, in the 

 motion of the satellites of Uranus, which, compared with the rest, 

 is retrograde. The axes of the planets are, as is well known, at 

 various degrees of inclination to their orbits ; for which there must 

 have been a cause in the circumstances under which the planets were 

 produced. The axis of Uranus is removed but eleven degrees from 

 the plane of his orbit : I suggest, as the explanation of the apparent 

 exception, that what we call the north pole of this planet is in reality 

 the south, the axis having passed across the plane of the orbit, so 

 that the planet may be said to be in that small measure upside down. 

 It will be observed, that between the admitted and the suggested 

 arrangement, there is only a difference of 22 degrees. 



(5.) A fifth member of this community was announced by M. 

 Henke in December 1845. 



In September 1846, a new planet of greater magnitude was dis- 

 covered beyond Uranus. Till our knowledge of this stranger is 

 somewhat greater and more settled, the text may be left undisturbed. 

 But it is meanwhile worthy of remark, tbat the extent of the solar 

 system is now double what it was supposed to be. 



(6.) Treatise on Astronomy. 



(7.) See " Professor Plateau, on the Phenomena presented by a 

 free Liquid Mass withdrawn from the action of Gravity." Taylor's 

 Scientific Memoirs, Nov. 1844. 



(8.) Among the most extraordinary phenomena of natural science 



