There is a good account of "Barry's" Brooklands exploits and successes featured in "Brough Superior - The Rolls Royce of Motor Cycles", by Ronald H. Clark, published in 1964.There's just over three pages of text and two very good photos, (winged collar and all!).

Don's picture above, dipicts the final version of the Brough outfit and the supercharger is clearly visible, mounted between the light alloy engine plates forward of the frame.