XII NOTES BY THE EDITOR 



planetary spaces ; and M. Babinet, before the French Academy, has 

 asserted that we have no evidence whatever upon the subject. Encke, 

 however, has taken occasion of the reappearance of the comet bearing 

 his name to again promulgate his belief in the existence of the ether, 

 and claims that its resisting influence on the above-named comet is 

 more manifest than ever ; while M. Faye, following Babinet, has re- 

 plied that he is unable to see how Encke's views can be maintained. 



Mr. Hind, the English astronomer, in a recent publication, offers a 

 protest against the names given to the young members of our plane- 

 tary family He says : 



" A few months since, my attention was directed, by Sir John Her- 

 schel, to the inconvenience and confusion which are being gradually 

 introduced into the nomenclature of the minor planets by the accept- 

 ance of names easily mistaken, either in speaking or writing, for others 

 belonging to planets previously discovered. I have been fully sensible 

 of the liability to error or misapprehension thereby induced, and am 

 desirous of recording a protest against any further continuance of 

 what must eventually become a positive nuisance to those who are 

 more particularly occupied with the observations and calculations 

 bearing upon this numerous group of planets. Thus, we have al- 

 ready : Thetis, Themis ; Lutetia, Lsetitia ; Iris, Isis ; Vesta, Hestia ; 

 Pallas, Pales. It will naturally be the wish of every discoverer of a 

 planet that his enfant trouve should be known to posterity by the name 

 which it has borne during his lifetime ; but if the practice to which 

 allusion is here made, be suffered to continue much longer, there is 

 certainly a probability that a day will arrive when, for the sake of 

 their general convenience, astronomers will consign these troublesome 

 names to oblivion, and substitute others less liable to engender confu- 

 sion. This consideration alone, we might suppose, would prove suffi- 

 ciently powerful to induce hesitation on the part of the discoverer 

 before accepting any name likely to be objected to on the score of 

 similarity with that of a planet previously found." 



The following is a list of the comets now known or supposed to be 

 periodical, or which belong to our solar system. The periodicity of 

 the last twelve, or of those whose computed times or revolution exceeds 

 fourteen years, with the exception of that of Halley, can, however, only 

 be rendered certain by their actual return at the expiration of the 

 predicted time. It will be seen that, in all but seven instances, 

 the comets bear the names of the astronomers by whom they were 

 first observed. In these seven exceptions, titles have been selected by 

 the discoverers, principally from the names of individuals whom, they 

 have desired to honor : 



Comet of Period in years. Discovered by 



Encke 3.3 



Blanpain ------- 4.8 



De Yico - - 5.5 



Pons 1818 



Blanpain 1819 



De Vico 1844 



