Patent

Patent:GB125455 24.04.1919 Barr, Archibald (P); Stroud, William (P) Barr and Stroud (P) Ltd : Improvements in Instruments for use in connection with Anti-aircraft Gunnery
Patent:GB125588 01.05.1919 Barr, A.; Stroud, W. Barr and Stroud (P) Ltd : A Deflection Indicator for use in connection with Anti-aircraft Guns.
Patent:GB126436 05.05.1919 MacGill, Charles Dalrymple (P) Barr and Stroud (P) Ltd : Improvements in Indicators of the Type Comprising Carry-over Gear

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