This morning my cat discovered a Nautilus feature I wasn't aware of. By sitting on my keyboard she split the Nautilus window into two panes. I am now at the office without my cat and unable to repeat the procedure. Is there a way to achieve this without a cat?
Open Nautilus and press F3.
Or
View-->Extra Pane
As in the picture.In addition to the F3 key press, you can also open the extra pane from the menu via mouse. View > Extra Pane.
You can also switch between panes with F6, create new tab in each of the two panes, with Ctrl-t, and navigate through tab of a pane with Alt-1, Alt-2, etc.