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thriving nation some obligation to utilize these advantages for the 

 welfare of mankind at large. Truly something besides material gold 

 is to be had there for the seeking ; the precious ores of intellectual 

 progress may there also be culled and stored away. 



The history of the progress of astronomical science has already 

 disclosed both the evil effects of neglecting these duties, and the 

 benefits which are likely to accrue when they are properly fulfilled. 

 When, in 1819, Encke computed the orbit of the comet of short 

 period, which justly bears his honoured name, and announced its 

 return in 1 822, that return would not have been observed had not 

 the zeal of a private individual, Sir Thomas Brisbane, established an 

 observatory at Paramatta in Australia, where, and where alone, its 

 reappearance was noted. Subsequently, the observatory at the Cape 

 of Good Hope was established ; but for many years, both there and 

 in Australia, the instrumental means provided for the observation of 

 comets were inadequate to the due discharge of the task. Now it is 

 well known that the motions of the comet of Encke first suggested 

 to astronomers the probability of the existence of some highly at- 

 tenuated medium or ether pervading the planetary spaces, in which 

 both planets and comets perform their revolutions. Every succeed- 

 ing return of this most interesting though diminutive body has 

 tended to confirm and strengthen that probability, which has now 

 well nigh, if not entirely, assumed the proportions of a physical fact. 

 But on each succeeding return of this wandering visitor, until 1855, 

 the distinguished veteran, who watches its motions with all the in- 

 terest and anxiety displayed by a fond parent towards a favourite 

 child, has had cause to deplore the deficiency of the instruments in 

 the Southern Hemisphere, to which the duty is necessarily assigned 

 of continuing the observations after the comet has ceased to be 

 visible in these latitudes. Before 1855, however, a more powerful 

 equatoreal had been supplied to Mr. Maclear, the able astronomer 

 at the Cape ; and now, to use the words of Encke himself in his 

 letter to the Astronomer Royal, "In the year 1855, thanks to the 

 skill of Mr. Maclear, and the beautiful 8^-foot equatoreal with wire 

 micrometer, the observations are perfectly on a level with the Eu- 

 ropean, which I take the opportunity of begging [you] to make 

 known to Mr. Maclear with my best thanks. It is a real pleasure now 

 constantly to see that the comet is observed at every return with an 



