When a German speaking tourist get on a local trolley, he asks everyone how to get where he's going. Finally the conductor tells him to just follow Mrs. C.J. Williams. When he does so, everyone gets upset.
It's a dull comedy because they run the set up to the mistake four or five times to make sure that the dullest member of the audience gets what is going on. That was the common idea of comedy at the time, and it's why Keystone, with its clearly marked stereotypes, fast cutting and not repeating every joke until everyone grew bored, was so popular. No one likes being talked down to, and that's what the slow, dull comedies of the era, like this one, did.