18 



from that date to September 26, 1846. I then reduced the apparent right 

 ascension and dechnation of these computed places of Neptune to Lalande's 

 clock and quadrant reading, for May 10, 1795. These would in this search 

 answer, without change, for the 8th. The actual results of the approximate 

 computation then made are as follows : 



Magnitude. 



Lalande's Clock 

 time. 



Lalande's Quad- 

 rant reading-. 



13'^ Sg- 2' 



59° 6' 7" 



14 5 17 



59 37 21 



14 11 32 



60 8 35 



t^ if in H. C. * 7.8 , 131^ 59"' 2' 59° 6' 7" , supposed western limit. 



most probable place, 

 supposed eastern limit. 



I next proceeded to prepare a list of stars on the nights of May 8 and May 

 10, having a clock reading from IS*" 50"' to 14'' 20'", and within 15' north or 

 south of the quadrant reading interpolated for the clock time from the above 

 locus. All the stars in this region, May 8, were below the 7.8 magnitude, and 

 were, moreover, found in Bessel's Zones. The only star in this region on the 

 10th of May, 1795, of the proper magnitude, and not included in Bessel's 

 Zones, read thus : 



Magnitude. Clock time of Transit. *(iuadrant reading. 



* 7.8 14° 11' 23".5 60° 7' 19": 



The place from the list of loci gave for this clock time — 



Neptune as a * 7.8 , 14" 11"' 2.3'.5 , 60° 7' 50" 



This astonishing coincidence was noticed by me in the evening of the 2d Feb- 

 ruary, (the weather being stormy.) It could not for a moment be doubted that 

 the star and planet were the same. The limits, it was believed, were sufficiently 

 extensive to include the Neptunian region. The magnitude 7.8 of Neptune was 

 one seldom omitted by Lalande. It was evident that Lalande had bestowed 

 his usual pains upon this region. No other star of the Histoire Celeste, even if 

 now missing, could with reason be supposed to be Neptune. It required only 

 that this star on search should be missing, to furnish a complete confirmation. 

 Accordingly, I drew up a statement to Lieut. Maury, the Superintendent, dated 

 February 2, giving an account of my labors, and mentioning these loci^ the par- 

 ticulars of the remarkable coincidence, and the grounds that induced me 

 strongly to believe in their identity, and, as a necessary consequence, that the 

 star would not be found in the group in which it had formerly been observed. 

 The Superintendent and my coadjutors in the Observatory, Professors Coffin 

 and Hubbard, after examining the list of Lalande's stars in the Neptunian 



• I did not notice till two weeks later the ( : ) colon placed after this observation by Lalande, indicating that the error in 

 declination might amount to 5'. My attention was first called to this doubtful circumstance by Prof. Peirce. 



