I've found them.

Opera placed them far, far away on the right margin.
To follow the proofs with pictures I had to "zoom" the page down
to 30%, what made whole thing illegible.

Another Geometry pages seem to be displayed the same way (virtual screen about tree times wider than the real one).

I looked at all Geometry pages and now only The Butterfly Theorem is too wide.

But now I found another thing:
the pop-up menus hide themselves under the Java applets.
It happens in Internet Explorer, Opera 7.54 and Mozilla 1.7b (on XP).

A piece of Poles and Polars page

>I looked at all Geometry pages and now only The
>Butterfly Theorem is too wide.

I very much appreciate your effort. Thank you.

I found and fixed the Problem with the Butterfly page.

>But now I found another thing:
>the pop-up menus hide themselves under the Java applets.
>It happens in Internet Explorer, Opera 7.54 and Mozilla 1.7b
>(on XP).

This is I am aware of, but have no solution to the problem. I shall probably remove the popups altohether.