[frabjous]

Thanks, guys. After some experiment, I think I've sorted this out. Details below.

Originally Posted by DaleDe

The side bar can be moved over. Just tap the right edge and move it to the right. The full window can be made wider to accommodate this.

I tried this, and it had no effect on the problem. Actually, the problem wasn't really with the length of the titles. The problem was something else, described below.

Originally Posted by mtravellerh

Try hard breaks in the heading

Actually, the problem was sort of the opposite.

This ePub was created through calibre. In the HTML source used to generate it, the chapter headings looked like this:

<h2 class="chaptertitle">CHAPTER 
XIII: THE AXIOM OF INFINITY AND LOGICAL TYPES</h2>

Calibre's chapter detection put items like the following into the toc.ncx zipped inside the epub:

    <navPoint id="cdd7d91a-1d3f-48d7-8546-19fc1a8ae123" playOrder="16">
      <navLabel>
        <text>CHAPTER 
XIII: THE AXIOM OF INFINITY AND LOGICAL TYPES</text>
      </navLabel>
      <content src="imp-c_split_16.html#chapter13"/>
    </navPoint>

I found that if I altered this file inside the epub to read:

    <navPoint id="cdd7d91a-1d3f-48d7-8546-19fc1a8ae123" playOrder="16">
      <navLabel>
        <text>CHAPTER XIII: THE AXIOM OF INFINITY AND LOGICAL TYPES</text>
      </navLabel>
      <content src="imp-c_split_16.html#chapter13"/>
    </navPoint>

Then things worked fine in ADE. I might bring this up in the calibre forum, and see if they want to alter their epub conversion script to avoid linebreaks in the toc.ncx file.