102 
e 
desire that whatever he might do for science should inure to 
his own country’s service, prevented him from yielding to 
the temptation. He considered the matter for a brief period, 
and then decided that he “ought not to work against time,” 
and the close of his researches was not reached till 1860. 
The second paper, published in July, 1854, is entitled, 
“Results of additional Investigations respecting the two 
Nuclei of Biela’s Comet.” In this short, but very elaborate 
and important memoir, Hupparp discussed the observa- 
tions of each nucleus in 1852, determining elements for 
each. And he arrived at the very remarkable results which 
seem now incontestable, “that notwithstanding the in- 
creased mutual distance of the two nuclei, their alternation, 
of relative brilliancy were much greater than those noticed 
in 1846; so great indeed, for several days, as to amount 
to alternations of visibility from day to day”; and that the 
observations at Berlin, 1845, November 29 and December 2, 
were of the primary nucleus, the second being invisible to 
the observers; while those of Cuatis, December 1 and 3, 
were of the secondary, the first being unseen. So that it is 
clear, both that we are in possession of observations of the 
second nucleus, mafe in the beginning of December, 1845, 
before the existence of two nuclei was suspected, and that 
even at that time occurred those singular alternations of 
light which were repeated in 1852. Furthermore, he made 
it highly probable that the preceding component, in 1846, 
was identical with the following one in 1852, and vice versd ; 
and finally, that the separation of the nuclei must have 
occurred not far from 316° of heliocentric longitude, corres- 
ponding to a time about five hundred days before the peri- 
helion passage of 1846. 
At the close of 1858, Husparp published a short papers 
containing a condensed notice of the condition of the prob- 
