Well, at the moment you don't seem to have those rules in place.
Actually the only rule you need to get it to work is:
Code:
.floatleft{
float:left;
}
the smalled image can be floated right ( or left for that matter) but don't actually need to be. They will stack on top of each other because there is nowhere else for them to go.
Having said that I guess that if someone text-only zooms the page then it work break so it might be better to float the small images too. In which case add this:
Code:
.floatrightclear{
float:right;
clear:right;
}
So, basically you were absolutely correct but the stylesheet rules are not being applied to the elements. It looks like the rules just aren't there.