htaccess - how to redirect to a new folder WITHOUT having that folder appear in the http path?

Our site currently resides in the root directory established by the web host.

We've set up a new site in a subfolder of our current site called '/blog/'.

We wish to make the new site (the one in the subfolder called /blog/) the live active site so that when users enter in our domain name, it automatically takes them to our new site in the /blog/ subfolder.

BUT - we don't want the name of the subfolder to appear in the user's browser's address bar. We still want the user's address bar to simply read our domain name, and NOT contain the word '/blog/' in the path.

Is this possible with htaccess? Or do we need to ask the web host to change the default folder?

Every attempt we've made (including the one referenced on the WordPress site: http://codex.wordpress.org/Giving_WordPress_Its_Own_Directory) results in the user being directed to the '/blog/' folder but it shows '/blog/' in the path.

thanks experts!