Dinghies racing on the River Thames.
Full title reads: "The Little Boats' Day - Perfect weather and the river at its best - provides a fine sailing breeze in competition for the West London Hospital Cup".
Various nice shots of dinghies racing on the River Thames. A big Thames barge - owned by Blue Circle Cement sails past. Nice shots as the little boats turn and race on the water.
N.B. Item found in Unidentified Gazettes reel.