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elements, “ which represent seven maxima observed in the 
course of three years, with reference to Piazzi’s estimations of 
magnitude in August, 1803,” viz. — 
Period— 138*6 days. 
Epochs 1860, Nov. 6. 
Having observed this star with more or less regularity 
during the past four years, it occurred to me that it would not 
be uninteresting to compare the elements resulting from a 
discussion of my own observations with those which had been 
deduced by Dr. Winnecke. The results of this discussion I 
have now the honour of presenting to the Manchester Literary 
and Philosophical Society. 
Projecting my observations in the usual way, I obtain the 
following dates of maxima and minima, with the correspond- 
ing magnitudes — 
Maxima. 
1861. Dec. 30*0 — 8*4 mag. 
1862. Oct. 5*0— 7*8 „ 
*1863. Nov. 19*4—7*6 „ 
1864. Aug. 16*3—7*5 „ 
1865. Jan. 7*3— 7*7 „ 
May 25*5—7*8 „ 
Oct. 5*5— 7*5 „ 
Minima. 
1861. Oct. 26*3 — 13*6 mag. 
1863. Sep. 18*0—13*2 „ 
1864. June 19*5—13*2 „ 
Nov. 4*0—13*1 „ 
1865. Aug. 6*3—12*8 „ 
Dec. 14*3—13*7 „ 
Treating the seven observed maxima according to Mr. 
Baxendell’s method, we obtain the following elements : — 
Period = 137*59 days. 
Epoch - 1864, April 4*95. 
Comparing the observed times of maximum with those 
calculated from these elements, and also from those of Dr. 
Winnecke, we obtain the following differences between calcu- 
lation and observation : — . 
* The projection of a series of his own observations of this maximum 
obligingly communicated to me by Mr. Baxendell, yields the following results, 
in gratifying accordance with my own : — Date of maximum, 1863, Nov. 18*9, 
mag. 7*5. 
