Lieutenant-Colonel Latham Valentine Stewart Blacker OBE (1 October 1887 – 19 April 1964) was a British Army officer and inventor of weapons; he invented the Blacker Bombard, from which was developed the Hedgehog anti-submarine spigot-mortar – and laid the basis of the PIAT anti-tank weapon.

He organized the event with Colonel Percy T. Etherton and was the chief observer,[3] writing a book First over Everest.

He took his weapons to his contacts at the War Office and was introduced to Major Millis Jefferis who engaged him and sent him to Coates Castle at Coates, West Sussex, from where his Blacker Bombard, a spigot mortar was developed.

Later one of his experimental guns based on the same principle was developed further by Jefferis and entered service as the PIAT.

For his contributions to the Bombard, PIAT, the Hedgehog anti-submarine mortar and Petard demolition mortar[a] he received £25,000 interim payment and a further £7,000 by the Royal Commission on Awards to Inventors (the body which determined the recompense to inventors whose ideas were used by the government during the war).