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necting P, and P, with one of the points of intersection of 1, lo, ls. 
So the demanded number is four: in the notation of SCHUBERT 
P? y4= 4, 
2. To find the number of conics passing through a given point 
P and resting on six right lines we again consider the case of 
lilo. l, lying in a plane p. Proper conics can only then satisfy, 
when they pass through P and a point of intersection of two of 
those right lines and intersect the remaining four lines; according 
to § 1 this number amounts to twelve. 
If a pair of lines are to satisfy, one of the right lines must pass 
through P and intersect one or two of the lines J,, /;, dg. 
When it meets /, it intersects p on the line connecting the traces 
of ls and /,, which is then the second right line of the pair. 
If P is situated on a line resting on /, and J/;, the second right 
line connects the trace of that line on @ with the trace of J. 
Six degenerated conics being found in this manner, the indicated 
number amounts to eighteen; Py’ = 18. 
3. We can now easily determine the number of conics resting 
on the eight right lines /;(¢= 1 to 8). 
If again 4, l,l; are lying in a plane g, we obtain a first 
conic passing through the traces of li, ls, los lj, ls with p; meeting 
each of 1,, J, B twice, it must be accounted for eight times. 
Moreover each conic passing through one of the points of inter- 
section of 4, l,/;, and reposing on each of the remaining six lines, 
satisfies the conditions; according to § 2 their number is equal to 54. 
The line connecting the traces Li, Ls of U, 4; on p forms with 
each line resting on Z4 Le, le, ly, lg a conic satisfying the proposed 
conditions. This consideration evidently furnishes 10 X 2 = 20 new 
answers. 
If at last 7 is the trace of a transversal of J,, ls, lo, ly, the line 
TLs forms with that transversal a conic of the indicated system. 
This gives rise to 5 x 2= 10 new answers. 
So we have v8—=8 J 54 4 20 +10= 92; in accordance with 
Lürorm (Journal fir Mathematik, Bd. 68) we have thus found that 
eight given right lines are intersected by 92 conics. 
Our considerations cannot be extended to cubic curves; for if to 
find vl? we suppose four right lines to lie in a plane «p, the traces 
of the remaining eight lines furnish an infinite number of cubic 
curves satisfying the question. 
