Include HTML page in an HTML page

I know how to do an include of an HTML page inside an ASP page, but I am 
basically trying to do the same thing with an HTML page - that is include
HTML 
within HTML - but it doesn't seem to be working when I test in a browser.
It 
displays fine in DW though!

 The only way to successfully create an include in HTML pages seems to be
to 
use the library method.

 Here is my include code:

 <!--#include file="../_includes/footer.html" -->

 Is this wrong for an HTML page?

 Thanks

 Mat