Manually scroll horizontally

[racoon]

Is there a way to scroll a long inset, e.g. a long equation, manually 
horizontally?

(I know that one can scroll with the cursor position but sometimes there 
is no possible cursor position, e.g. when there is only a line number. 
One way to get around this is to move the cursor just after the inset. I 
was just wondering whether there is another way to scroll.)

Best

Daniel