Getting get archives from other blog on same database

First: please look at the sketch for the situation

I have two WP blogs running on the same database.
On blog 2 I use a pulldown with the titles of the posts of that blog.
Using the next code:

<select name=\"archive-dropdown\" onChange='document.location.href=this.options[this.selectedIndex].value;'>
<option value=\"\"><?php echo attribute_escape(__('SELECT ACT project')); ?></option>
<?php wp_get_archives('type=postbypost&amp;format=option&amp;cat=1'); ?> </select>

But how can I get those titles (of posts of blog 2) in the pulldown of blog 1?
The only thing I get right now are the posts from blog 1 (using the code right above).

I know I have to use play with SQL queries… but how and where?

(sorry for my bad english)