Scanned from the 11 Nov 1905 issue of Scientific American
The Brooke 1 powerboat that had a 400HP engine was produced by Brooke Motor Company, of Lowescroft, England
The six cylinder engine was quite the monster, each cylinder had a 10" bore with an 8" stroke, that is 628 cubic inches (10.3 liters) per cylinder for a total of 3768 CI (61.8 litres), 400hp at 1000rpm