It refers to a Victorian stage instruction to the actor, in the script. See 

It's about as clear as I can find as a stage instruction. I'm guessing from the script that accompanies the footnote that the E refers to enter. The footnote says L. means Left, but I think from the context it means "leave". Good luck.


On Saturday, March 14, 2015 1:33 PM, Scott Holmes <[log in to unmask]> wrote:

There is a remark in the review, as posted on the site
" "Mark Twain's" first peek-a-boo at R.1.E. was greeted with
laughter, ..."

What is R.1.E. ?