You can find the free JURN add-on for the popular Firefox web browser on this page.

Simply scroll down the page until you see JURN in the list. Handily, it’s located next to JSTOR UK…

After you install it, locate the small search box alongside your browser’s address bar. You should now be able to easily toggle between JURN and other engines, via a simple drop-down menu…

Choosing JURN in this way allows you to highlight and right-click on any phase in any web page, then have JURN do a search…

The set of results open in a new window.

That’s it! Thanks to Pattrice Jones for making the add-on.