TwentyTen CSS float left issue

In the content area, I have two sliders stacked on top of each other. I want the text to flow around the sliders. Float left works fine, until I insert an <h> tag, then the remaining text falls beneath the sliders.

I tested using an image instead of the slide shows, & got the same behavior. It also takes the formatting off the
<li> tags.

Here is a screen shot without the <h> tag.

https://pic100.picturetrail.com/VOL728/2745263/23613161/405220601.jpg

And here, with the <h> tag inserted after the 2nd paragraph.

https://pic100.picturetrail.com/VOL728/2745263/23613161/405220602.jpg

https://www.ads-software.com/extend/themes/twentyten/