23 



tory, Mauvais' ci'itical examination of them, and detection of the other sup- 

 pressed observation of May 8 — the surprising confirmation of the truth and of 

 the excellence of the two observations, by the perfect representation of the 

 computed two days' motion of the planet — all these facts have, through other 

 channels, been made matters of history. 



SECTION 3. 



COMPUTATIONS CONFIRMING THE AUTHENTICITY OF LALANDE'S PRINTED OBSERVATIONS. 



No. 33. In order to confirm or set aside this hypothesis of the Lalande 

 observation, I employed my leisure from professional duties in the completion 

 of the plan originally proposed to myself, of inserting in the equations of con- 

 dition a term depending on the daily variation of the radius vector, subject to 

 the equable description of areas. 



For this purpose I computed new Disturbed Elements IV from the normal 

 places of September 28th and December 27th, already given, using for the 

 constant radius vector the value in Elements II. 



ELEMENTS IV. —DISTURBED ELLIPSE. 



Tt = unknown. ) -^ ^ inAr, 



SI = 129° 51' 13".50 \ ""• ^1- J=^"- ^' l^'^^- 



i = 1 45 35 .66 



e = unknown. 



Ij, = 21". 416035 



5 = unknown. 



T = 165!'t^//-j 



rt-\-v = <, =^ 327° 34' 19" .03 m. noon, Jan. 1, 1847. 



From these elements I computed an Ephemeris IV of Neptune, and com- 

 pared with it all the observations received, from August 4th, 1846, to April 30th, 

 1847. This list of observations amounts to 113 American, and 366 European. 

 The discussion of all the direct meridian observations of Neptune gave the fol- 

 lowing normal corrections of Ephemeris IV, in R. A. and Dec. : 



1847. 



Sept. 28, 



+ 0".3 



— 0".6 



Oct. 8, 



+ .4 



— .6 



" 18, 



+ .4 



— .6 



- 28, 



+ .2 



— .5 



Nov. 7, 



+ .0 



— .8 



" 17, 



+ .2 



— 1 .1 



" 27, 



-(- .3 



— 1 .0 



Dec. 7, 



+ .7 



— 1 .0 



