Great race for girls in swimsuits in speedboats!
United States of America.
Introductory intertitle reads: "Here's a new one from Uncle Sam... abandon clothes - join the ship and race for home. (And the water takes the hindmost)."
M/S of four girls sitting on chairs in the open air. They all wear white dresses. A man has a starting flag and says something like "Girls, are you ready for the on again off again gone again championships?" They yell "YES!" and take off their tights and dresses to reveal swimsuits.
They run into a lake and jump into speedboats which are co-piloted by boys. One of the boats is called the Grapefruit Kid and another is the Michigan Kid. The boats look to be travelling really fast and there are lots of squeals from the girls. I presume they race to the other side of the lake and back.
Returning to shore the boats are run right up onto the beach and the girls have to jump out and run back to the chairs sitting down. We see them in the background, one falls over backwards after she has sat on the chair. One of the boy racers seems to have burned his fingers on the speedboat.
A woman stands on the speedboat and a man in swimming suit shakes her hand. Presumably they are the winning team. She is wearing her dress again, even though it is all ripped right down the front.
Note: great film showing girls having lots of fun.