Unfortunately, the author used \\ in place of // in these links and Firefox does not correct that automatically:

<ul id="MenuBar2" class="MenuBarHorizontal">
  <li><a href="http:\\www.lorch.ca/index.html">Home</a></li>
  <li><a href="http:\\www.lorch.ca/about.html">About</a>
  <li><a href="http:\\www.lorch.ca/services.html">Services</a>
  <li><a href="http:\\www.lorch.ca/clients.html">Clients</a></li>
  <li><a href="http:\\www.lorch.ca/contact.html">Contact</a></li>
</ul>

The problem is that this has not been put in the code. The same site in chrome does not show this address with the \\ it shows correctly. The author which is myself did not put this address in it appears that firefox is doing this to the address.

The backslashes are really in the page source.
The page source in Google Chrome shows them as well, but GC ignores those backslashes and convert them automatically to forward slashes.
Firefox doesn't do that and requires forward slashes.

You can use these in inspect the page source:

• Firefox > Web Developer > Page Source
• Tools > Web Developer > Page Source (Ctrl+U)
• Right-click on a web page to open the context menu and select View Page Source

javascript:(function(){var e=document.querySelectorAll('a[href]'),t=[],i;for(i=0;E=e[i];i++){if(/\\/.test(unescape(E.getAttribute('href')))){t.push(E.href);}}alert(t.join('\n'))})()