132 Mr. Lassell at Malta. 



seen, especially when more than 8 or 9 seconds central distance 

 from the planet, even in bright moonlight, and without any 

 extraordinary atmospherical circumstances, that I have arrived 

 at the firm conviction that the planet is attended by no other 

 satellite which will bear comparison in magnitude with the 

 known one — not greater certainly than Dione or Rhea, among 

 Saturn's satellites, bears to Titan. It may be indeed possible 

 that a faint satellite several minutes' distant might exist, though 

 I have no suspicion of any, and one so situated would be very 

 difficult to recognise among the numerous minute stars which 

 a telescope so large as this generally reveals.'" 



Equally careful observations were made on Uranus, con- 

 firming the belief that this planet only possesses the two 

 satellites first discovered by Sir William Herschel, and the 

 others (interior) discovered by Mr. Lassell in 1851. 



Mr. Lassell considers that "in all future treatises on 

 Astronomy, the proper number of known satellites should be 

 assigned to these two planets — namely to Uranus four, and to 

 Neptune one." 



To facilitate observations on Saturn, Mr. Lassell appends 

 to his letter an Ephemeris of the five inner satellites of 

 Saturn for February, March, and April, 1865. 



A series of drawings of Mars during his late opposition was 

 much interrupted, as the weather for two months (November 

 and December) was ' c quite as unfavourable as it is usually in 

 England at the same season.-" 



A good many drawings have been made of remarkable 

 nebulae, including an elaborate one not yet finished of the 

 great nebulae in Orion. 



