Add the Split Command to Outlook’s Quick Access Toolbar
If your message, document or spreadsheet is long, readers may have to scroll up and down a lot. But if you split the window in two, each pane can be scrolled independently of the other. So you can see the beginning and end of the message, document or spreadsheet at the same time.
Office 2013 did away with the split bar that appeared at the top of the vertical scroll-bar, but the feature is not gone. Instead add the Split feature to Outlook’s Quick Access toolbar.