Need help with count expression

I need a bit of help with count() as so far I've 
been unable to construct a valid expression to obtain what  I need
Basically 
what I'm trying to do is generate Table numbers relative to Chapters but only 
for tables that contain a title element.  Here's an example 
structure
 

<chapter>
    <p>...</p>
    <table 
class="topic/table">
        <title class="table/title">(should 
resolve to Table 1.1) ...<title>
        ...
    
</table>
     <table class="topic/table>...</table>
    
<section>
       <table> ...</table>
        
<table>
            <title class="table/title">(should resolve to 
Table 1.2) ...<title>
            ...
        </table>       
    </chapter>
<chapter>
    <table 
class="topic/table>>...</table>
    <section>
        
<p>
            <table class="topic/table">
                
<title class="table/title">Should resolve to Table 2.1 
</title>
                ...
            </table>
        
</p>
    </section>
</chapter>
 
Getting the 
chapter number is easy enough 'count(preceding::chapter)+1' but what I'm having 
problems with is the Table number in relation to the chapter
I can get the 
Table position in relation to the document 
via
select="count(preceding::*[contains(@class,' topic/table 
')]/*[contains(@class,' topic/title ')])+1"
but I'm not quite sure how to 
combine the 2 expressions to give me the proper count in relationship to the 
current <chapter>
 
Any help would be much appreciated.
-Kit